Dosage Forms
Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Capsule, Oral, as sulfate:
Reyataz: 150 mg, 200 mg, 300 mg [contains fd&c blue #2 (indigotine)]
Generic: 150 mg, 200 mg, 300 mg
Packet, Oral, as sulfate:
Reyataz: 50 mg (30 ea) [contains aspartame; orange-vanilla flavor]
Pharmacology
Mechanism of Action
Binds to the site of HIV-1 protease activity and inhibits cleavage of viral Gag-Pol polyprotein precursors into individual functional proteins required for infectious HIV. This results in the formation of immature, noninfectious viral particles.
Pharmacokinetics/Pharmacodynamics
Absorption
Rapid; enhanced with food
Distribution
CSF: Plasma concentration ratio (range): 0.0021 to 0.0226
Metabolism
Hepatic, primarily by cytochrome P450 isoenzyme CYP3A; also undergoes biliary elimination; major biotransformation pathways include mono-oxygenation and deoxygenation; minor pathways for parent drug or metabolites include glucuronidation, N-dealkylation, hydrolysis and oxygenation with dehydrogenation; 2 minor inactive metabolites have been identified
Excretion
Feces (79%, 20% of total dose as unchanged drug); urine (13%, 7% of total dose as unchanged drug)
Time to Peak
Plasma: 2 to 3 hours
Half-Life Elimination
Unboosted therapy: 7 to 8 hours; Boosted therapy (with ritonavir): 9 to 18 hours; 12 hours in patients with hepatic impairment
Protein Binding
86%; binds to both alpha1-acid glycoprotein and albumin (similar affinity)
Use in Specific Populations
Special Populations: Renal Function Impairment
The mean Cmax was 9% lower, AUC was 19% higher, and Cmin was 96% higher in subjects with severe renal impairment not undergoing hemodialysis.
Use: Labeled Indications
HIV-1 Infection:
Treatment of HIV-1 infection in combination with other antiretroviral agents in patients ≥3 months weighing ≥5 kg
Limitations of use:
Not recommended for use in pediatric patients <3 months due to the risk of kernicterus
Use in treatment-experienced patients should be guided by the number of baseline primary protease inhibitor resistance substitutions
Contraindications
Hypersensitivity (eg, Stevens-Johnson syndrome, erythema multiforme, toxic skin eruptions) to atazanavir or any component of the formulation; concurrent therapy with alfuzosin, cisapride, elbasvir/grazoprevir, glecaprevir/pibrentasvir, ergot derivatives (dihydroergotamine, ergonovine, ergotamine, methylergonovine), indinavir, irinotecan, lovastatin, lurasidone (when atazanavir is coadministered with ritonavir), midazolam (oral), nevirapine, pimozide, rifampin, sildenafil (when used for pulmonary artery hypertension [eg, Revatio]), simvastatin, St. John's wort, or triazolam
Canadian labeling: Additional contraindications (not in US labeling): Concomitant use of quinidine
Dosage and Administration
Dosing: Adult
Treatment of HIV-1 infection:
Oral:
Antiretroviral-naive patients: Atazanavir 300 mg once daily plus ritonavir 100 mg or cobicistat 150 mg once daily or atazanavir 400 mg once daily in patients unable to tolerate ritonavir.
Antiretroviral-experienced patients: Atazanavir 300 mg once daily plus ritonavir 100 mg or cobicistat 150 mg once daily. Note: Atazanavir without ritonavir is not recommended in antiretroviral-experienced patients with prior virologic failure.
Pregnant patients, antiretroviral naive or experienced: Atazanavir 300 mg once daily plus ritonavir 100 mg once daily. Some experts recommend increasing the dose to atazanavir 400 mg once daily plus ritonavir 100 mg once daily in the second and third trimesters (HHS [perinatal] 2019); the manufacturer recommends this dose increase only for antiretroviral-experienced pregnant females in the second and third trimesters who are also receiving either tenofovir disoproxil fumarate or an H2 antagonist. Use is not recommended if both tenofovir disoproxil fumarate and an H2 antagonist are used (HHS [perinatal] 2019). Postpartum dosage adjustment not needed. Observe patient for adverse events, especially within 2 months after delivery.
Dosage adjustments for concomitant therapy:
Coadministration with efavirenz:
Antiretroviral-naive patients: Atazanavir 400 mg plus ritonavir 100 mg given with efavirenz 600 mg (all once daily but administered at different times; atazanavir and ritonavir with food and efavirenz on an empty stomach).
Antiretroviral-experienced patients: Concurrent use not recommended due to decreased atazanavir exposure.
Coadministration with didanosine buffered or enteric-coated formulations: Administer atazanavir 2 hours before or 1 hour after didanosine buffered or enteric coated formulations
Coadministration with H2 antagonists:
Antiretroviral-naive patients: Atazanavir 300 mg plus ritonavir 100 mg given simultaneously with, or at least 10 hours after an H2 antagonist equivalent dose of ≤80 mg famotidine/day
Patients unable to tolerate ritonavir: Atazanavir 400 mg once daily given at least 2 hours before or at least 10 hours after an H2 antagonist equivalent daily dose of ≤40 mg famotidine (single dose ≤20 mg)
Antiretroviral-experienced patients: Atazanavir 300 mg plus ritonavir 100 mg given simultaneously with, or at least 10 hours after an H2 antagonist equivalent dose of ≤40 mg famotidine/day
Antiretroviral-experienced pregnant patients in the second or third trimester: Atazanavir 400 mg plus ritonavir 100 mg simultaneously with, or at least 10 hours after an H2 antagonist. Note: Use not recommended if both tenofovir disoproxil fumarate and an H2 antagonist are used.
Coadministration with proton pump inhibitors:
Antiretroviral-naive patients: Atazanavir 300 mg plus ritonavir 100 mg given 12 hours after a proton pump inhibitor equivalent dose of ≤20 mg omeprazole/day
Antiretroviral-experienced patients: Concurrent use not recommended.
Coadministration with tenofovir disoproxil fumarate:
Antiretroviral-naive patients: Atazanavir 300 mg plus ritonavir 100 mg given with tenofovir disoproxil fumarate 300 mg (all as a single daily dose)
Antiretroviral-experienced patients: Atazanavir 300 mg plus ritonavir 100 mg given with tenofovir disoproxil fumarate 300 mg (all as a single daily dose); if H2 antagonist coadministered (not to exceed equivalent daily dose of ≤40 mg famotidine), increase atazanavir to 400 mg (plus ritonavir 100 mg) once daily
Antiretroviral-experienced pregnant patients in the second or third trimester: Atazanavir 400 mg plus ritonavir 100 mg. Note: Use not recommended if tenofovir disoproxil fumarate and an H2 antagonist are used.
Dosing: Geriatric
Refer to adult dosing.
Dosing: Pediatric
HIV-1 infection, treatment: Note: Gene mutation and antiretroviral (ARV) resistance patterns should be evaluated (refer to www.IASUSA.org for more information) when necessary. Use in combination with other ARV agents. Oral capsules and oral powder are not interchangeable; product-specific dosing should be used; the bioavailability of oral capsules was observed to be higher than that of oral powder (Kiser 2011).
Boosted regimen (preferred regimen):
Oral powder: Infants ≥3 months, Children, and Adolescents: Oral:
5 to <15 kg: Atazanavir 200 mg (4 packets) once daily plus ritonavir 80 mg once daily. In antiretroviral-naive patients weighing 5 to <10 kg unable to tolerate this dose, may use atazanavir 150 mg (3 packets) once daily plus ritonavir 80 mg once daily with close HIV viral load monitoring.
15 to <25 kg: Atazanavir 250 mg (5 packets) once daily plus ritonavir 80 mg once daily.
≥25 kg (who cannot swallow a capsule): Atazanavir 300 mg (6 packets) once daily plus ritonavir 100 mg once daily.
Oral capsule: Note: Recommended to use the capsule formulation in any child ≥15 kg who can swallow a capsule whole (HHS [pediatric] 2019).
Children ≥6 years weighing ≥15 kg and Adolescents <18 years: Oral:
15 kg to <35 kg: Atazanavir 200 mg once daily plus ritonavir 100 mg once daily.
≥35 kg: Atazanavir 300 mg once daily plus ritonavir 100 mg once daily or cobicistat 150 mg once daily (Tybost prescribing information 2019).
Adolescents ≥18 years: Oral: Atazanavir 300 mg once daily plus ritonavir 100 mg or cobicistat 150 mg once daily.
Unboosted regimen: Note: Boosted atazanavir dosing regimen is preferred; guidelines do not recommend unboosted regimens unless patient is ≥13 years and not receiving concurrent tenofovir (either alafenamide or disoproxil fumarate forms); closely monitor plasma concentrations to ensure adequate concentrations are achieved (HHS [pediatric] 2019). Oral powder should not be used for unboosted regimens.
Antiretroviral-naive patients: Note: Data indicates that children and adolescents <18 years may require higher doses (mg/kg and mg/m2) than those predicted by adult dosing guidelines to achieve adequate levels for unboosted atazanavir therapy (Kiser 2011).
>6 to <13 years: Oral capsule: Oral: Atazanavir 520 mg/m2/dose once daily (HHS [pediatric] 2019; Kiser 2011).
13 to <18 years: Oral capsule: Oral: Atazanavir 620 mg/m2/dose once daily (HHS [pediatric] 2019; Kiser 2011).
Adolescents ≥18 years: Oral capsule: Oral: Atazanavir 400 mg once daily.
Dosing adjustments for concomitant therapy: Note: Other potentially significant interactions may exist, requiring dose or frequency adjustment, additional monitoring, and/or selection of alternative therapy. Consult drug interactions database for more detailed information. See Administration: Pediatric for additional information about spacing of doses with concomitant agents that affect gastric pH.
Coadministration with H2-receptor antagonists: Antiretroviral-naive patients: Unboosted regimens:
Children ≥6 years and Adolescents <18 years: Do not use concomitantly (HHS [pediatric] 2019; Kiser 2011).
Adolescents ≥18 years: Oral capsule: Oral: Atazanavir 400 mg once daily given at least 2 hours before or at least 10 hours after an H2 antagonist; dosage of H2-receptor antagonist must be limited to the equivalent daily dose of ≤40 mg famotidine (single dose: ≤20 mg).
Coadministration with proton pump inhibitor: Antiretroviral-experienced patients: Infants ≥3 months, Children, and Adolescents: Concurrent use not recommended.
Coadministration with efavirenz: Adolescents ≥18 years:
Antiretroviral-naive patient: Oral capsule: Oral: Atazanavir 400 mg plus ritonavir 100 mg given with efavirenz 600 mg (all once daily but administered at different times; atazanavir and ritonavir with food and efavirenz on an empty stomach).
Antiretroviral-experienced patients: Concurrent use not recommended due to decreased atazanavir exposure.
Coadministration with tenofovir disoproxil fumarate:
Infants ≥3 months, Children, and Adolescents: Tenofovir disoproxil fumarate (TDF) decreases atazanavir concentrations; do not use unboosted regimens with concomitant TDF therapy (HHS [adult] 2019; HHS [pediatric] 2019).
Adolescents ≥18 years: Oral capsule: Oral:
Antiretroviral-naive patients: Atazanavir 300 mg plus ritonavir 100 mg given with tenofovir disoproxil fumarate 300 mg (all as a single daily dose).
Antiretroviral-experienced patients: Atazanavir 300 mg plus ritonavir 100 mg given with tenofovir disoproxil fumarate 300 mg (all as a single daily dose); if H2 antagonist coadministered (not to exceed equivalent daily dose of ≤40 mg famotidine), increase atazanavir to 400 mg (plus ritonavir 100 mg) once daily.
Administration
Administer with food. Administer atazanavir 2 hours before or 1 hour after didanosine buffered formulations, didanosine enteric-coated capsules, other buffered medications, or antacids. Administer atazanavir (with ritonavir) simultaneously with, or at least 10 hours after, H2-receptor antagonists; administer atazanavir (without ritonavir) at least 2 hours before or at least 10 hours after H2-receptor antagonist. Administer atazanavir (with ritonavir) 12 hours after proton pump inhibitor.
Additional formulation specific information:
Oral capsules: Swallow capsules whole, do not open.
Oral powder: Mixing with food: Using a spoon, mix the recommended number of oral powder packets with a minimum of one tablespoon of food (such as applesauce or yogurt) in a small container. Feed the mixture to the patient. Add an additional one tablespoon of food to the container, mix, and feed the patient the residual mixture.
Mixing with a beverage such as milk or water in a small drinking cup: Using a spoon, mix the recommended number of oral powder packets with a minimum of 30 mL of the beverage in a drinking cup. Have the patient drink the mixture. Add an additional 15 mL more of beverage to the cup, mix, and have the patient drink the residual mixture. If water is used, food should also be taken at the same time.
Administer the entire dosage of oral powder (mixed in the food or beverage) within one hour of preparation (may leave the mixture at room temperature during this one hour period). Ensure that the patient eats or drinks all the food or beverage that contains the powder. Additional food may be given after consumption of the entire mixture. Administer ritonavir immediately following oral powder administration.
Dietary Considerations
Must be taken with food; enhances absorption.
Storage
Capsules: Store at 25°C (77°F); excursions are permitted between 15°C and 30°C (59°F and 86°F).
Oral powder: Store below 30°C (86°F). Store oral powder in the original packet and do not open until ready to use. Once the oral powder is mixed with food or beverage, it may be kept at 20°C to 30°C (68°F to 86°F) for up to 1 hour prior to administration.
Atazanavir Images
Drug Interactions
Abacavir: Protease Inhibitors may decrease the serum concentration of Abacavir. Monitor therapy
Abemaciclib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Abemaciclib. Management: In patients taking abemaciclib at a dose of 200 mg or 150 mg twice daily, reduce the dose to 100 mg twice daily when combined with strong CYP3A4 inhibitors. In patients taking abemaciclib 100 mg twice daily, decrease the dose to 50 mg twice daily. Consider therapy modification
Acalabrutinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Acalabrutinib. Avoid combination
Ado-Trastuzumab Emtansine: CYP3A4 Inhibitors (Strong) may increase serum concentrations of the active metabolite(s) of Ado-Trastuzumab Emtansine. Specifically, strong CYP3A4 inhibitors may increase concentrations of the cytotoxic DM1 component. Avoid combination
Alfuzosin: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Alfuzosin. Avoid combination
Alfuzosin: Protease Inhibitors may increase the serum concentration of Alfuzosin. Avoid combination
Alitretinoin (Systemic): CYP3A4 Inhibitors (Strong) may increase the serum concentration of Alitretinoin (Systemic). Management: Consider reducing the alitretinoin dose to 10 mg when used together with strong CYP3A4 inhibitors. Monitor for increased alitretinoin effects/toxicities if combined with a strong CYP3A4 inhibitor. Consider therapy modification
Almotriptan: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Almotriptan. Management: Limit initial almotriptan adult dose to 6.25 mg and maximum adult dose to 12.5 mg/24-hrs when used with a strong CYP3A4 inhibitor. Avoid concurrent use in patients with impaired hepatic or renal function. Consider therapy modification
Alosetron: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Alosetron. Monitor therapy
Alpelisib: BCRP/ABCG2 Inhibitors may increase the serum concentration of Alpelisib. Management: Avoid coadministration of BCRP/ABCG2 inhibitors and alpelisib due to the potential for increased alpelisib concentrations and toxicities. If coadministration cannot be avoided, closely monitor for increased alpelisib adverse reactions. Consider therapy modification
ALPRAZolam: CYP3A4 Inhibitors (Strong) may increase the serum concentration of ALPRAZolam. Management: Consider using an alternative agent that is less likely to interact. If combined, monitor for increased therapeutic/toxic effects of alprazolam if combined with a strong CYP3A4 inhibitor. Consider therapy modification
Amiodarone: Atazanavir may increase the serum concentration of Amiodarone. Monitor therapy
AmLODIPine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of AmLODIPine. Monitor therapy
Antacids: May decrease the absorption of Atazanavir. Consider therapy modification
Antidiabetic Agents: Hyperglycemia-Associated Agents may diminish the therapeutic effect of Antidiabetic Agents. Monitor therapy
Apixaban: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Apixaban. Monitor therapy
Aprepitant: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Aprepitant. Avoid combination
ARIPiprazole: CYP3A4 Inhibitors (Strong) may increase the serum concentration of ARIPiprazole. Management: See full interaction monograph for details. Consider therapy modification
ARIPiprazole Lauroxil: CYP3A4 Inhibitors (Strong) may increase serum concentrations of the active metabolite(s) of ARIPiprazole Lauroxil. Management: Please refer to the full interaction monograph for details concerning the recommended dose adjustments. Consider therapy modification
Astemizole: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Astemizole. Management: Drugs listed as exceptions to this monograph are discussed in further detail in separate drug interaction monographs. Avoid combination
Asunaprevir: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Asunaprevir. Avoid combination
Asunaprevir: OATP1B1/1B3 (SLCO1B1/1B3) Inhibitors may increase the serum concentration of Asunaprevir. Avoid combination
AtorvaSTATin: Protease Inhibitors may increase the serum concentration of AtorvaSTATin. Management: See full monograph for recommended dose limits. Avoid atorvastatin with tipranavir/ritonavir. Consider therapy modification
Avanafil: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Avanafil. Avoid combination
Avapritinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Avapritinib. Avoid combination
Axitinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Axitinib. Management: Avoid concurrent use of axitinib with any strong CYP3A inhibitor whenever possible. If a strong CYP3A inhibitor must be used with axitinib, a 50% axitinib dose reduction is recommended. Consider therapy modification
Barnidipine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Barnidipine. Avoid combination
Bedaquiline: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Bedaquiline. Management: Limit duration of concurrent use of bedaquiline with CYP3A4 inhibitors to no more than 14 days, unless the benefit of continued use outweighs the possible risks. Monitor for toxic effects of bedaquiline. Exceptions discussed in separate monographs. Consider therapy modification
Belinostat: Atazanavir may increase the serum concentration of Belinostat. Avoid combination
Benperidol: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Benperidol. Monitor therapy
Benzhydrocodone: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Benzhydrocodone. Specifically, the concentration of hydrocodone may be increased. Monitor therapy
Betamethasone (Ophthalmic): CYP3A4 Inhibitors (Strong) may increase the serum concentration of Betamethasone (Ophthalmic). Monitor therapy
Bictegravir: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Bictegravir. Monitor therapy
Blonanserin: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Blonanserin. Avoid combination
Bortezomib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Bortezomib. Monitor therapy
Bosentan: May decrease the serum concentration of Atazanavir. Atazanavir may increase the serum concentration of Bosentan. Management: Concurrent use of atazanavir (without ritonavir) and bosentan is not recommended. Bosentan dose adjustments are required when used together with atazanavir/ritonavir. Consider therapy modification
Bosutinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Bosutinib. Avoid combination
Brentuximab Vedotin: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Brentuximab Vedotin. Specifically, concentrations of the active monomethyl auristatin E (MMAE) component may be increased. Monitor therapy
Brexpiprazole: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Brexpiprazole. Management: Reduce brexpiprazole dose 50% with strong CYP3A4 inhibitors; reduce to 25% of usual if used with both a moderate CYP3A4 inhibitor and a CYP2D6 inhibitor in patients not being treated for MDD, or strong CYP3A4 inhibitor used in a CYP2D6 poor metabolizer. Consider therapy modification
Brigatinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Brigatinib. Management: Avoid concurrent use of brigatinib with strong CYP3A4 inhibitors when possible. If combination cannot be avoided, reduce the brigatinib dose by approximately 50%, rounding to the nearest tablet strength (ie, from 180 mg to 90 mg, or from 90 mg to 60 mg). Consider therapy modification
Brinzolamide: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Brinzolamide. Monitor therapy
Bromocriptine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Bromocriptine. Avoid combination
Budesonide (Nasal): CYP3A4 Inhibitors (Strong) may increase the serum concentration of Budesonide (Nasal). Monitor therapy
Budesonide (Oral Inhalation): CYP3A4 Inhibitors (Strong) may increase the serum concentration of Budesonide (Oral Inhalation). Monitor therapy
Budesonide (Systemic): CYP3A4 Inhibitors (Strong) may increase the serum concentration of Budesonide (Systemic). Avoid combination
Budesonide (Topical): CYP3A4 Inhibitors (Strong) may increase the serum concentration of Budesonide (Topical). Management: Per US prescribing information, avoid this combination. Canadian product labeling does not recommend strict avoidance. If combined, monitor for excessive glucocorticoid effects as budesonide exposure may be increased. Consider therapy modification
Buprenorphine: May decrease the serum concentration of Atazanavir. Atazanavir may increase the serum concentration of Buprenorphine. Management: Avoid this combination in patients un-boosted atazanavir due to possible decreased atazanavir concentrations. This combination is not contraindicated in patients also receiving ritonavir, but monitoring for buprenorphine toxicity is recommended. Avoid combination
BusPIRone: CYP3A4 Inhibitors (Strong) may increase the serum concentration of BusPIRone. Management: Limit the buspirone dose to 2.5 mg daily and monitor patients for increased buspirone effects/toxicities if combined with strong CYP3A4 inhibitors. Consider therapy modification
Cabazitaxel: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Cabazitaxel. Management: Concurrent use of cabazitaxel with strong inhibitors of CYP3A4 should be avoided when possible. If such a combination must be used, consider a 25% reduction in the cabazitaxel dose. Consider therapy modification
Cabozantinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Cabozantinib. Management: Avoid use of a strong CYP3A4 inhibitor with cabozantinib if possible. If combined, cabozantinib dose adjustments are recommended and vary based on the cabozantinib product used and the indication for use. See monograph for details. Consider therapy modification
Calcifediol: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Calcifediol. Monitor therapy
Calcium Channel Blockers (Nondihydropyridine): Protease Inhibitors may decrease the metabolism of Calcium Channel Blockers (Nondihydropyridine). Increased serum concentrations of the calcium channel blocker may increase risk of AV nodal blockade. Management: Avoid concurrent use when possible. If used, monitor for CCB toxicity. The manufacturer of atazanavir recommends a 50% dose reduction for diltiazem be considered. Saquinavir, tipranavir, and darunavir/cobicistat use with bepridil is contraindicated. Consider therapy modification
Cannabidiol: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Cannabidiol. Monitor therapy
Cannabis: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Cannabis. More specifically, tetrahydrocannabinol and cannabidiol serum concentrations may be increased. Monitor therapy
CarBAMazepine: May increase the metabolism of Protease Inhibitors. Protease Inhibitors may decrease the metabolism of CarBAMazepine. Consider therapy modification
Cariprazine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Cariprazine. Management: Cariprazine dose reductions of 50% are required; specific recommended management varies slightly for those stable on cariprazine versus those just starting cariprazine. See prescribing information or full interaction monograph for details. Consider therapy modification
Cat's Claw: May increase the serum concentration of Atazanavir. Monitor therapy
Ceritinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Ceritinib. Management: If such combinations cannot be avoided, the ceritinib dose should be reduced by approximately one-third (to the nearest 150 mg). Resume the prior ceritinib dose after cessation of the strong CYP3A4 inhibitor. Exceptions discussed in separate monographs. Consider therapy modification
Cilostazol: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Cilostazol. Management: Consider reducing the cilostazol dose to 50 mg twice daily in adult patients who are also receiving strong inhibitors of CYP3A4. Consider therapy modification
Cinacalcet: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Cinacalcet. Monitor therapy
Cisapride: Protease Inhibitors may increase the serum concentration of Cisapride. This may result in QTc prolongation and malignant cardiac arrhythmias. Management: Drugs listed as exceptions to this monograph are discussed in further detail in separate drug interaction monographs. Avoid combination
Cladribine: BCRP/ABCG2 Inhibitors may increase the serum concentration of Cladribine. Management: Avoid concomitant use of BCRP inhibitors during the 4 to 5 day oral cladribine treatment cycles whenever possible. If combined, consider dose reduction of the BCRP inhibitor and separation in the timing of administration. Consider therapy modification
Clarithromycin: Protease Inhibitors may diminish the therapeutic effect of Clarithromycin. Specifically, certain protease inhibitors may decrease formation of the active 14-hydroxy-clarithromycin metabolite, which may negatively impact clarithromycin effectiveness vs. H. influenzae and other non-MAC infections. Protease Inhibitors may increase the serum concentration of Clarithromycin. Clarithromycin dose adjustment in renally impaired patients may be needed. Clarithromycin may increase the serum concentration of Protease Inhibitors. Management: Saquinavir is contraindicated with clarithromycin. Avoid clarithromycin adult doses over 1000 mg/day with a protease inhibitor. Further dose reductions may be needed with impaired renal function. Consider alternative antimicrobial for a non-MAC infection. Consider therapy modification
Clofazimine: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Monitor therapy
CloZAPine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of CloZAPine. Management: Drugs listed as exceptions to this monograph are discussed in further detail in separate drug interaction monographs. Monitor therapy
Cobimetinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Cobimetinib. Avoid combination
Codeine: CYP3A4 Inhibitors (Strong) may increase serum concentrations of the active metabolite(s) of Codeine. Monitor therapy
Colchicine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Colchicine. Management: Colchicine is contraindicated in patients with impaired renal or hepatic function who are also receiving a strong CYP3A4 inhibitor. In those with normal renal and hepatic function, reduce colchicine dose as directed. See full monograph for details. Consider therapy modification
Conivaptan: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Conivaptan. Avoid combination
Conivaptan: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Avoid combination
Copanlisib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Copanlisib. Management: If concomitant use of copanlisib and strong CYP3A4 inhibitors cannot be avoided, reduce the copanlisib dose to 45 mg. Monitor patients for increased copanlisib effects/toxicities. Consider therapy modification
Corticosteroids (Orally Inhaled): CYP3A4 Inhibitors (Strong) may increase the serum concentration of Corticosteroids (Orally Inhaled). Management: Orally inhaled fluticasone propionate with a strong CYP3A4 inhibitor is not recommended. Exceptions: Beclomethasone (Oral Inhalation); Triamcinolone (Systemic). Monitor therapy
Corticosteroids (Systemic): CYP3A4 Inhibitors (Strong) may increase the serum concentration of Corticosteroids (Systemic). Exceptions: MethylPREDNISolone; PrednisoLONE (Systemic); PredniSONE. Monitor therapy
Crizotinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Crizotinib. Management: Avoid concomitant use of crizotinib and strong CYP3A4 inhibitors whenever possible. If combined use cannot be avoided, decrease the crizotinib dose to 250 mg daily. Exceptions are discussed in separate monographs. Consider therapy modification
Cyclophosphamide: Protease Inhibitors may enhance the adverse/toxic effect of Cyclophosphamide. Specifically, the incidences of neutropenia, infection, and mucositis may be increased. Monitor therapy
CycloSPORINE (Systemic): Protease Inhibitors may increase the serum concentration of CycloSPORINE (Systemic). CycloSPORINE (Systemic) may increase the serum concentration of Protease Inhibitors. Consider therapy modification
CycloSPORINE (Systemic): CYP3A4 Inhibitors (Strong) may increase the serum concentration of CycloSPORINE (Systemic). Consider therapy modification
CYP3A4 Inducers (Moderate): May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy
CYP3A4 Inducers (Strong): May increase the metabolism of CYP3A4 Substrates (High risk with Inducers). Management: Consider an alternative for one of the interacting drugs. Some combinations may be specifically contraindicated. Consult appropriate manufacturer labeling. Consider therapy modification
CYP3A4 Inhibitors (Moderate): May decrease the metabolism of CYP3A4 Substrates (High risk with Inhibitors). Monitor therapy
CYP3A4 Inhibitors (Strong): May decrease the metabolism of CYP3A4 Substrates (High risk with Inhibitors). Consider therapy modification
CYP3A4 Substrates (High risk with Inhibitors): CYP3A4 Inhibitors (Strong) may decrease the metabolism of CYP3A4 Substrates (High risk with Inhibitors). Exceptions: Alitretinoin (Systemic); AmLODIPine; Benzhydrocodone; Buprenorphine; Gefitinib; HYDROcodone; Mirtazapine; Praziquantel; Telithromycin; Vinorelbine. Consider therapy modification
Dabrafenib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Dabrafenib. Avoid combination
Daclatasvir: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Daclatasvir. Management: Decrease the daclatasvir dose to 30 mg once daily if combined with a strong CYP3A4 inhibitor. No dose adjustment is needed when daclatasvir is used with darunavir/cobicistat. Consider therapy modification
Dapoxetine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Dapoxetine. Avoid combination
Dapsone (Systemic): May enhance the adverse/toxic effect of Atazanavir. Specifically, the risk of hyperbilirubinemia may be increased. Monitor therapy
Dasatinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Dasatinib. Management: This combination should be avoided if possible. If combined, dasatinib dose reductions are recommended. See full monograph for details. Drugs listed as exceptions to this monograph are discussed in further detail in separate drug interaction monographs. Consider therapy modification
Deferasirox: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy
Deflazacort: CYP3A4 Inhibitors (Strong) may increase serum concentrations of the active metabolite(s) of Deflazacort. Management: Administer one third of the recommended deflazacort dose when used together with a strong or moderate CYP3A4 inhibitor. Consider therapy modification
Delamanid: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Delamanid. Management: Increase ECG monitoring frequency if delamanid is combined with strong CYP3A4 inhibitors due to the risk for QTc interval prolongation. Continue frequent ECG assessments throughout full delamanid treatment period. Exceptions discussed separately. Consider therapy modification
Delavirdine: Protease Inhibitors may decrease the serum concentration of Delavirdine. Delavirdine may increase the serum concentration of Protease Inhibitors. Consider therapy modification
DexAMETHasone (Ophthalmic): CYP3A4 Inhibitors (Strong) may increase the serum concentration of DexAMETHasone (Ophthalmic). Monitor therapy
Didanosine: May decrease the serum concentration of Atazanavir. Specifically, the buffered formulation of didanosine may decrease atazanavir absorption. Atazanavir may decrease the serum concentration of Didanosine. Reported with enteric coated didanosine capsules. Management: To avoid therapeutic failure of atazanavir the drug should be administered 2 hours before or 1 hour after didanosine. This recommendation applies to both buffered didanosine products and enteric coated didanosine products. Consider therapy modification
Disulfiram: Atazanavir may diminish the therapeutic effect of Disulfiram. Monitor therapy
DOCEtaxel: CYP3A4 Inhibitors (Strong) may increase the serum concentration of DOCEtaxel. Management: Avoid the concomitant use of docetaxel and strong CYP3A4 inhibitors when possible. If combined use is unavoidable, consider a 50% docetaxel dose reduction and monitor for increased docetaxel toxicities. Consider therapy modification
Dofetilide: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Dofetilide. Monitor therapy
Domperidone: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Domperidone. Management: Drugs listed as exceptions to this monograph are discussed in further detail in separate drug interaction monographs. Avoid combination
Doxercalciferol: CYP3A4 Inhibitors (Strong) may decrease serum concentrations of the active metabolite(s) of Doxercalciferol. Monitor therapy
DOXOrubicin (Conventional): CYP3A4 Inhibitors (Strong) may increase the serum concentration of DOXOrubicin (Conventional). Management: Seek alternatives to strong CYP3A4 inhibitors in patients treated with doxorubicin whenever possible. One U.S. manufacturer (Pfizer Inc.) recommends that these combinations be avoided. Consider therapy modification
Dronabinol: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Dronabinol. Monitor therapy
Dronedarone: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Dronedarone. Management: Drugs listed as exceptions to this monograph are discussed in further detail in separate drug interaction monographs. Avoid combination
Drospirenone: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Drospirenone. Management: Drospirenone use is contraindicated specifically when the strong CYP3A4 inhibitors atazanavir and cobicistat are administered concurrently. Caution should be used when drospirenone is coadministered with other strong CYP3A4 inhibitors. Consider therapy modification
Dutasteride: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Dutasteride. Monitor therapy
Duvelisib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Duvelisib. Management: Reduce the dose of duvelisib to 15 mg twice a day when used together with a strong CYP3A4 inhibitor. Consider therapy modification
Efavirenz: May decrease the serum concentration of Atazanavir. Management: When used with efavirenz, the adult atazanavir dose should be 400 mg daily, boosted with ritonavir 100 mg daily or cobicistat 150 mg daily, for treatment-naive patients only; treatment-experienced patients should not use atazanavir with efavirenz. Consider therapy modification
Elagolix: OATP1B1/1B3 (SLCO1B1/1B3) Inhibitors may increase the serum concentration of Elagolix. Avoid combination
Eletriptan: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Eletriptan. Avoid combination
Elexacaftor, Tezacaftor, and Ivacaftor: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Elexacaftor, Tezacaftor, and Ivacaftor. Management: When combined with strong CYP3A4 inhibitors, administer two elexacaftor/tezacaftor/ivacaftor tablets (100 mg/50 mg/75 mg) in the morning, twice a week, approximately 3 to 4 days apart. No evening doses of ivacaftor (150 mg) alone should be administered. Consider therapy modification
Eliglustat: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Eliglustat. Management: Use should be avoided under some circumstances. See full drug interaction monograph for details. Consider therapy modification
Eluxadoline: Atazanavir may increase the serum concentration of Eluxadoline. Management: Decrease the eluxadoline dose to 75 mg twice daily if combined with atazanavir and monitor patients for increased eluxadoline effects/toxicities. Consider therapy modification
Elvitegravir: Atazanavir may increase the serum concentration of Elvitegravir. Specifically, atazanavir/ritonavir may increase the concentration of elvitegravir. Management: When elvitegravir is combined with atazanavir/ritonavir, the dose of elvitegravir should be reduced to 85 mg once daily and the dose of atazanavir/ritonavir should be 300 mg/100 mg once daily. Avoid the use of atazanavir/cobicistat and elvitegravir. Consider therapy modification
Encorafenib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Encorafenib. Management: Avoid concomitant use of encorafenib and strong CYP3A4 inhibitors whenever possible. If concomitant administration is unavoidable, decrease the encorafenib dose. See monograph for details. Consider therapy modification
Enfortumab Vedotin: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Enfortumab Vedotin. Specifically, concentrations of the active monomethyl auristatin E (MMAE) component may be increased. Monitor therapy
Enfuvirtide: Protease Inhibitors may increase the serum concentration of Enfuvirtide. Enfuvirtide may increase the serum concentration of Protease Inhibitors. Monitor therapy
Entrectinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Entrectinib. Management: Avoid strong CYP3A4 inhibitors during treatment with entrectinib. Reduce dose to 100 mg/day if combination cannot be avoided in adults and those 12 yrs of age or older with a BSA of at least 1.5 square meters. No alternative dosing provided for others. Consider therapy modification
Enzalutamide: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Management: Concurrent use of enzalutamide with CYP3A4 substrates that have a narrow therapeutic index should be avoided. Use of enzalutamide and any other CYP3A4 substrate should be performed with caution and close monitoring. Consider therapy modification
Eplerenone: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Eplerenone. Avoid combination
Erdafitinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Erdafitinib. Management: Avoid concomitant use of erdafitinib and strong CYP3A4 inhibitors when possible. If combined, monitor closely for erdafitinib adverse reactions and consider dose modifications accordingly. Consider therapy modification
Ergot Derivatives: Protease Inhibitors may increase the serum concentration of Ergot Derivatives. Exceptions: Cabergoline; Nicergoline; Pergolide. Avoid combination
Erlotinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Erlotinib. Management: Avoid use of this combination when possible. When the combination must be used, monitor the patient closely for the development of severe adverse reactions, and if such severe reactions occur, reduce the erlotinib dose (in 50 mg decrements). Consider therapy modification
Estrogen Derivatives: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Estrogen Derivatives. Monitor therapy
Estrogen Derivatives (Contraceptive): Protease Inhibitors may decrease the serum concentration of Estrogen Derivatives (Contraceptive). Management: Use oral contraceptives containing at least 35mcg ethinyl estradiol with atazanavir/ritonavir, or no more than 30mcg in patients receiving atazanavir alone. Use of an alternative, non-hormonal contraceptive is recommended with other protease inhibitors. Consider therapy modification
Eszopiclone: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Eszopiclone. Management: Limit the eszopiclone dose to 2 mg daily when combined with strong CYP3A4 inhibitors and monitor for increased eszopiclone effects and toxicities (eg, somnolence, drowsiness, CNS depression). Consider therapy modification
Etizolam: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Etizolam. Management: Consider use of lower etizolam doses when using this combination; specific recommendations concerning dose adjustment are not available. Monitor clinical response to the combination closely. Consider therapy modification
Etravirine: Atazanavir may increase the serum concentration of Etravirine. Etravirine may decrease the serum concentration of Atazanavir. Management: The combination of etravirine and atazanavir should be avoided unless atazanavir is boosted with ritonavir. The use of cobicistat instead of ritonavir has not been evaluated and is not recommended. Consider therapy modification
Everolimus: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Everolimus. Avoid combination
Evogliptin: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Evogliptin. Monitor therapy
Fedratinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Fedratinib. Management: Consider alternatives when possible. If used together, decrease fedratinib dose to 200 mg/day. After the inhibitor is stopped, increase fedratinib to 300 mg/day for the first 2 weeks and then to 400 mg/day as tolerated. Consider therapy modification
FentaNYL: CYP3A4 Inhibitors (Strong) may increase the serum concentration of FentaNYL. Management: Monitor patients closely for several days following initiation of this combination, and adjust fentanyl dose as necessary. Consider therapy modification
Fesoterodine: CYP3A4 Inhibitors (Strong) may increase serum concentrations of the active metabolite(s) of Fesoterodine. Management: Avoid fesoterodine doses greater than 4 mg daily in adult patients who are also receiving strong CYP3A4 inhibitors. Consider therapy modification
Fexinidazole [INT]: Atazanavir may enhance the QTc-prolonging effect of Fexinidazole [INT]. Avoid combination
Flibanserin: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Flibanserin. Avoid combination
Fluticasone (Nasal): CYP3A4 Inhibitors (Strong) may increase the serum concentration of Fluticasone (Nasal). Avoid combination
Fluticasone (Oral Inhalation): CYP3A4 Inhibitors (Strong) may increase the serum concentration of Fluticasone (Oral Inhalation). Management: Use of orally inhaled fluticasone propionate with strong CYP3A4 inhibitors is not recommended. Use of orally inhaled fluticasone furoate with strong CYP3A4 inhibitors should be done with caution. Monitor patients using such a combination more closely. Consider therapy modification
Fluvastatin: Atazanavir may increase the serum concentration of Fluvastatin. Consider therapy modification
Fosaprepitant: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Fosaprepitant. Avoid combination
Fosnetupitant: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Monitor therapy
Fostamatinib: CYP3A4 Inhibitors (Strong) may increase serum concentrations of the active metabolite(s) of Fostamatinib. Monitor therapy
Fusidic Acid (Systemic): May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Avoid combination
Galantamine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Galantamine. Monitor therapy
Garlic: May decrease the serum concentration of Protease Inhibitors. Management: Concurrent use of garlic supplements with protease inhibitors is not recommended. If this combination is used, monitor closely for altered serum concentrations/effects of protease inhibitors, and particularly for signs/symptoms of therapeutic failure. Consider therapy modification
Gefitinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Gefitinib. Monitor therapy
Gilteritinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Gilteritinib. Management: Consider alternatives to the use of a strong CYP3A4 inhibitor with gilteritinib. If the combination cannot be avoided, monitor more closely for evidence of gilteritinib toxicities. Consider therapy modification
Glasdegib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Glasdegib. Management: Consider alternatives to this combination when possible. If the combination must be used, monitor closely for evidence of QT interval prolongation and other adverse reactions to glasdegib. Consider therapy modification
Glecaprevir and Pibrentasvir: Atazanavir may increase the serum concentration of Glecaprevir and Pibrentasvir. Avoid combination
Grazoprevir: Atazanavir may increase the serum concentration of Grazoprevir. Avoid combination
GuanFACINE: CYP3A4 Inhibitors (Strong) may increase the serum concentration of GuanFACINE. Management: Reduce the guanfacine dose by 50% when initiating this combination. Consider therapy modification
Halofantrine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Halofantrine. Management: Drugs listed as exceptions to this monograph are discussed in further detail in separate drug interaction monographs. Avoid combination
Histamine H2 Receptor Antagonists: May decrease the serum concentration of Atazanavir. Management: Specific dose limitations and administration guidelines exist; consult full interaction monograph or atazanavir prescribing information. Consider therapy modification
HYDROcodone: CYP3A4 Inhibitors (Strong) may increase the serum concentration of HYDROcodone. Monitor therapy
Ibrutinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Ibrutinib. Management: Avoid concomitant use of ibrutinib and strong CYP3A4 inhibitors. If a strong CYP3A4 inhibitor must be used short-term (eg, anti-infectives for 7 days or less), interrupt ibrutinib therapy until the strong CYP3A4 inhibitor is discontinued. Avoid combination
Idelalisib: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Avoid combination
Ifosfamide: CYP3A4 Inhibitors (Strong) may decrease serum concentrations of the active metabolite(s) of Ifosfamide. Monitor therapy
Iloperidone: CYP3A4 Inhibitors (Strong) may increase serum concentrations of the active metabolite(s) of Iloperidone. Specifically, concentrations of the metabolites P88 and P95 may be increased. CYP3A4 Inhibitors (Strong) may increase the serum concentration of Iloperidone. Management: Reduce iloperidone dose by half when administered with a strong CYP3A4 inhibitor. Consider therapy modification
Imatinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Imatinib. Monitor therapy
Imidafenacin: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Imidafenacin. Monitor therapy
Indinavir: Atazanavir may enhance the adverse/toxic effect of Indinavir. Indinavir may enhance the adverse/toxic effect of Atazanavir. Avoid combination
Irinotecan Products: CYP3A4 Inhibitors (Strong) may increase serum concentrations of the active metabolite(s) of Irinotecan Products. Specifically, serum concentrations of SN-38 may be increased. CYP3A4 Inhibitors (Strong) may increase the serum concentration of Irinotecan Products. Avoid combination
Isavuconazonium Sulfate: CYP3A4 Inhibitors (Strong) may increase serum concentrations of the active metabolite(s) of Isavuconazonium Sulfate. Specifically, CYP3A4 Inhibitors (Strong) may increase isavuconazole serum concentrations. Management: Combined use is considered contraindicated per US labeling. Lopinavir/ritonavir (and possibly other uses of ritonavir doses less than 400 mg every 12 hours) is treated as a possible exception to this contraindication despite strongly inhibiting CYP3A4. Avoid combination
Istradefylline: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Istradefylline. Management: Limit the maximum istradefylline dose to 20 mg daily when combined with strong CYP3A4 inhibitors and monitor for increased istradefylline effects/toxicities. Consider therapy modification
Ivabradine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Ivabradine. Avoid combination
Ivacaftor: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Ivacaftor. Management: Ivacaftor dose reductions are required; consult full monograph content for age- and weight-specific recommendations. Consider therapy modification
Ivosidenib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Ivosidenib. Management: Avoid use of a strong CYP3A4 inhibitor with ivosidenib whenever possible. When combined use is required, reduce the ivosidenib dose to 250 mg once daily. Drugs listed as exceptions are discussed in further detail in separate drug interaction monographs. Consider therapy modification
Ixabepilone: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Ixabepilone. Consider therapy modification
Lacosamide: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Lacosamide. Monitor therapy
LamoTRIgine: Atazanavir may decrease the serum concentration of LamoTRIgine. Monitor therapy
Lapatinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Lapatinib. Management: If an overlap in therapy cannot be avoided, consider reducing lapatinib adult dose to 500 mg/day during, and within 1 week of completing, treatment with the strong CYP3A4 inhibitor. Avoid combination
Larotrectinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Larotrectinib. Management: Avoid use of strong CYP3A4 inhibitors with larotrectinib. If this combination cannot be avoided, reduce the larotrectinib dose by 50%. Increase to previous dose after stopping the inhibitor after a period of 3 to 5 times the inhibitor half-life. Consider therapy modification
Lefamulin: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Lefamulin. Management: Avoid concomitant use of lefamulin tablets and strong inhibitors of CYP3A4. Avoid combination
Lemborexant: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Lemborexant. Avoid combination
Lercanidipine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Lercanidipine. Avoid combination
Levamlodipine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Levamlodipine. Monitor therapy
Levobupivacaine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Levobupivacaine. Monitor therapy
Levomilnacipran: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Levomilnacipran. Management: Do not exceed a maximum adult levomilnacipran dose of 80 mg/day in patients also receiving strong CYP3A4 inhibitors. Consider therapy modification
Lomitapide: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Lomitapide. Avoid combination
Lorlatinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Lorlatinib. Management: Avoid use of lorlatinib with strong CYP3A4 inhibitors. If the combination cannot be avoided, reduce the lorlatinib dose from 100 mg once daily to 75 mg once daily, or from 75 mg once daily to 50 mg once daily. Consider therapy modification
Lorlatinib: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Management: Avoid concurrent use of lorlatinib with any CYP3A4 substrates for which a minimal decrease in serum concentrations of the CYP3A4 substrate could lead to therapeutic failure and serious clinical consequences. Consider therapy modification
Lovastatin: Protease Inhibitors may increase the serum concentration of Lovastatin. Avoid combination
Lovastatin: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Lovastatin. Avoid combination
Lumacaftor and Ivacaftor: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Lumacaftor and Ivacaftor. Management: When initiating or resuming lumacaftor/ivacaftor after a therapy interruption of 7 days or more, reduce the lumacaftor/ivacaftor dose to 1 tablet daily or 1 packet of oral granules every other day for the first week, and then resume the standard dose. Consider therapy modification
Lumateperone: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Lumateperone. Avoid combination
Lumefantrine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Lumefantrine. Monitor therapy
Lurasidone: Atazanavir may increase the serum concentration of Lurasidone. Management: Atazanavir labeling recommends reducing the lurasidone dose as directed by the lurasidone labeling for moderate CYP3A4 inhibitors when used together with lurasidone. Consider therapy modification
Macitentan: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Macitentan. Avoid combination
Manidipine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Manidipine. Management: Consider avoiding concomitant use of manidipine and strong CYP3A4 inhibitors. If combined, monitor closely for increased manidipine effects and toxicities. Manidipine dose reductions may be required. Consider therapy modification
Maraviroc: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Maraviroc. Management: Reduce the adult dose of maraviroc to 150 mg twice daily when used with a strong CYP3A4 inhibitor. Do not use maraviroc with strong CYP3A4 inhibitors in patients with Clcr less than 30 mL/min. Consider therapy modification
Meperidine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Meperidine. Monitor therapy
MethylPREDNISolone: CYP3A4 Inhibitors (Strong) may increase the serum concentration of MethylPREDNISolone. Management: Consider methylprednisolone dose reduction in patients receiving strong CYP3A4 inhibitors and monitor for increased steroid related adverse effects. Consider therapy modification
Midazolam: Protease Inhibitors may increase the serum concentration of Midazolam. Management: Oral midazolam contraindicated with all protease inhibitors. IV midazolam contraindicated with fosamprenavir and nelfinavir; other protease inhibitors recommend caution, close monitoring, and consideration of lower IV midazolam doses with concurrent use. Avoid combination
Midostaurin: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Midostaurin. Management: Seek alternatives to the concomitant use of midostaurin and strong CYP3A4 inhibitors if possible. If concomitant use cannot be avoided, monitor patients for increased risk of adverse reactions. Exceptions are discussed in separate monographs. Consider therapy modification
MiFEPRIStone: CYP3A4 Inhibitors (Strong) may increase the serum concentration of MiFEPRIStone. Management: Limit mifepristone adult dose, when used for treatment of hyperglycemia in Cushing's syndrome, to a maximum of 900 mg/day when combined with a strong CYP3A4 inhibitor. Monitor for increased mifepristone toxicity regardless of dose or indication. Consider therapy modification
MiFEPRIStone: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Management: Minimize doses of CYP3A4 substrates, and monitor for increased concentrations/toxicity, during and 2 weeks following treatment with mifepristone. Avoid cyclosporine, dihydroergotamine, ergotamine, fentanyl, pimozide, quinidine, sirolimus, and tacrolimus. Consider therapy modification
Minocycline (Systemic): May decrease the serum concentration of Atazanavir. Monitor therapy
Minoxidil (Systemic): Atazanavir may increase the serum concentration of Minoxidil (Systemic). Monitor therapy
Mirodenafil: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Mirodenafil. Management: Consider using a lower dose of mirodenafil when used with strong CYP3A4 inhibitors. Monitor for increased mirodenafil effects/toxicities with the use of this combination. Consider therapy modification
Mirtazapine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Mirtazapine. Monitor therapy
Mitotane: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Management: Doses of CYP3A4 substrates may need to be adjusted substantially when used in patients being treated with mitotane. Consider therapy modification
Naldemedine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Naldemedine. Monitor therapy
Nalfurafine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Nalfurafine. Monitor therapy
Naloxegol: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Naloxegol. Avoid combination
Nefazodone: Protease Inhibitors may increase the serum concentration of Nefazodone. Management: Consider alternatives to, or reduced doses of, nefazodone in patients treated with HIV protease inhibitors. Monitor patients receiving these combinations closely for toxic effects of nefazodone. Consider therapy modification
Neratinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Neratinib. Avoid combination
Netupitant: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Monitor therapy
Nevirapine: Atazanavir may increase the serum concentration of Nevirapine. Nevirapine may decrease the serum concentration of Atazanavir. Avoid combination
Nilotinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Nilotinib. Management: Avoid if possible. If combination needed, decrease nilotinib to 300 mg once/day for patients with resistant or intolerant Ph+ CML or to 200 mg once/day for patients with newly diagnosed Ph+ CML in chronic phase. Exceptions discussed in separate monograph. Consider therapy modification
NiMODipine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of NiMODipine. Avoid combination
Nisoldipine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Nisoldipine. Avoid combination
Olaparib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Olaparib. Management: Avoid use of strong CYP3A4 inhibitors in patients being treated with olaparib, if possible. If such concurrent use cannot be avoided, the dose of olaparib should be reduced to 100 mg twice daily. Consider therapy modification
Ombitasvir, Paritaprevir, and Ritonavir: Atazanavir may increase the serum concentration of Ombitasvir, Paritaprevir, and Ritonavir. Specifically, the paritaprevir component may increase significantly. Avoid combination
Ombitasvir, Paritaprevir, Ritonavir, and Dasabuvir: Atazanavir may increase the serum concentration of Ombitasvir, Paritaprevir, Ritonavir, and Dasabuvir. Specifically, the paritaprevir component may increase significantly. Management: These agents can be combined if the atazanavir dose is 300 mg daily, atazanavir is administered in the morning at the same time as the ombitasvir/paritaprevir/ritonavir/dasabuvir combination product, and atazanavir is given without additional ritonavir. Consider therapy modification
Orlistat: May decrease the serum concentration of Antiretroviral Agents. Monitor therapy
Ospemifene: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Ospemifene. Monitor therapy
Oxybutynin: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Oxybutynin. Monitor therapy
OxyCODONE: CYP3A4 Inhibitors (Strong) may enhance the adverse/toxic effect of OxyCODONE. CYP3A4 Inhibitors (Strong) may increase the serum concentration of OxyCODONE. Serum concentrations of the active metabolite oxymorphone may also be increased. Consider therapy modification
PACLitaxel (Conventional): Atazanavir may increase the serum concentration of PACLitaxel (Conventional). Management: Use of paclitaxel or other narrow therapeutic index CYP2C8 substrates with atazanavir without concurrent ritonavir is not recommended. If paclitaxel is used with ritonavir-boosted atazanavir, no significant interaction is expected. Avoid combination
Palbociclib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Palbociclib. Avoid combination
Panobinostat: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Panobinostat. Management: Reduce the panobinostat dose to 10 mg when it must be used with a strong CYP3A4 inhibitor. Consider therapy modification
Parecoxib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Parecoxib. Monitor therapy
Paricalcitol: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Paricalcitol. Monitor therapy
PAZOPanib: BCRP/ABCG2 Inhibitors may increase the serum concentration of PAZOPanib. Avoid combination
Pexidartinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Pexidartinib. Management: Avoid use of pexidartinib with strong CYP3A4 inhibitors if possible. If combined use cannot be avoided, the pexidartinib dose should be reduced. Decrease 800 mg or 600 mg daily doses to 200 mg twice daily. Decrease doses of 400 mg/day to 200 mg/day. Consider therapy modification
Pimavanserin: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Pimavanserin. Management: Decrease the pimavanserin dose to 10 mg daily when combined with strong CYP3A4 inhibitors. Consider therapy modification
Pimecrolimus: CYP3A4 Inhibitors (Strong) may decrease the metabolism of Pimecrolimus. Monitor therapy
Pimozide: Protease Inhibitors may increase the serum concentration of Pimozide. Avoid combination
Pimozide: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Pimozide. Avoid combination
Piperaquine: CYP3A4 Inhibitors (Strong) may enhance the QTc-prolonging effect of Piperaquine. CYP3A4 Inhibitors (Strong) may increase the serum concentration of Piperaquine. Management: Avoid concomitant use of piperaquine and strong CYP3A4 inhibitors when possible. If the combination cannot be avoided, frequent ECG monitoring is recommended due to the risk for QTc prolongation. Exceptions are discussed separately. Consider therapy modification
Pitavastatin: Atazanavir may increase the serum concentration of Pitavastatin. Monitor therapy
Polatuzumab Vedotin: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Polatuzumab Vedotin. Exposure to unconjugated MMAE, the cytotoxic small molecule component of polatuzumab vedotin, may be increased. Monitor therapy
PONATinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of PONATinib. Management: Per ponatinib U.S. prescribing information, the adult starting dose of ponatinib should be reduced to 30 mg daily during treatment with any strong CYP3A4 inhibitor. Consider therapy modification
Posaconazole: May increase the serum concentration of Atazanavir. Monitor therapy
Pranlukast: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Pranlukast. Monitor therapy
Praziquantel: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Praziquantel. Monitor therapy
PrednisoLONE (Systemic): CYP3A4 Inhibitors (Strong) may increase the serum concentration of PrednisoLONE (Systemic). Monitor therapy
PredniSONE: CYP3A4 Inhibitors (Strong) may increase the serum concentration of PredniSONE. Monitor therapy
Progestins (Contraceptive): Atazanavir may increase the serum concentration of Progestins (Contraceptive). However, atazanavir may lead to decreased ethinyl estradiol concentrations and decreased effectiveness of oral contraceptive products. Management: Consider an alternative or additional method of contraception, particularly with combined estrogen/progestin products. Depot medroxyprogesterone acetate may be used without a need for additional contraception. Consider therapy modification
Propafenone: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Propafenone. Management: Drugs listed as exceptions to this monograph are discussed in further detail in separate drug interaction monographs. Monitor therapy
Protease Inhibitors: May increase the serum concentration of other Protease Inhibitors. Management: Atazanavir--indinavir combination contraindicated. Tipranavir/ritonavir or atazanavir/ritonavir not recommended with other protease inhibitors (PI). Darunavir/cobicistat not recommended with PI that require boosting.Other combos may require dose changes. Consider therapy modification
Proton Pump Inhibitors: May decrease the serum concentration of Atazanavir. Management: See full drug interaction monograph for details. Consider therapy modification
QUEtiapine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of QUEtiapine. Management: In quetiapine treated patients, reduce quetiapine to one-sixth of regular dose after starting strong CYP3A4 inhibitor. In those on strong CYP3A4 inhibitors, start quetiapine at lowest dose and up-titrate as needed. Exceptions discussed separately. Consider therapy modification
QuiNIDine: Atazanavir may increase the serum concentration of QuiNIDine. Monitor therapy
Radotinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Radotinib. Avoid combination
Ramelteon: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Ramelteon. Monitor therapy
Ranolazine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Ranolazine. Avoid combination
Reboxetine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Reboxetine. Consider therapy modification
Red Yeast Rice: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Red Yeast Rice. Specifically, concentrations of lovastatin and related compounds found in Red Yeast Rice may be increased. Avoid combination
Regorafenib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Regorafenib. Avoid combination
Repaglinide: Atazanavir may increase the serum concentration of Repaglinide. Management: Use of repaglinide or other narrow therapeutic index CYP2C8 substrates with atazanavir without concurrent ritonavir is not recommended. If repaglinide is used with ritonavir-boosted atazanavir, no significant interaction is expected. Avoid combination
Retapamulin: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Retapamulin. Management: Avoid this combination in patients less than 2 years old. No action is required in other populations. Monitor therapy
Revefenacin: OATP1B1/1B3 (SLCO1B1/1B3) Inhibitors may increase serum concentrations of the active metabolite(s) of Revefenacin. Avoid combination
Ribociclib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Ribociclib. Management: Avoid use of ribociclib with strong CYP3A4 inhibitors when possible; if combined use cannot be avoided, reduce ribociclib dose to 400 mg once daily. Exceptions are discussed in separate monographs. Consider therapy modification
Rifabutin: Atazanavir may increase serum concentrations of the active metabolite(s) of Rifabutin. Atazanavir may increase the serum concentration of Rifabutin. Management: Reduce rifabutin doses. Clinical guidelines recommend 150 mg daily or 300 mg 3 times per week with atazanavir/ritonavir. Atazanavir labeling recommends a decrease of at least 75%, to 150 mg every other day or 150 mg 3 times per week for adults. Consider therapy modification
RifAMPin: May decrease the serum concentration of Atazanavir. Avoid combination
Rilpivirine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Rilpivirine. Monitor therapy
Riociguat: Protease Inhibitors may increase the serum concentration of Riociguat. Management: Consider starting with a reduced riociguat dose of 0.5 mg three times a day (for adults). Patients receiving such a combination should also be monitored extra closely for signs or symptoms of hypotension. Consider therapy modification
RomiDEPsin: CYP3A4 Inhibitors (Strong) may increase the serum concentration of RomiDEPsin. Monitor therapy
Rosiglitazone: Atazanavir may increase the serum concentration of Rosiglitazone. Monitor therapy
Rosuvastatin: Protease Inhibitors may increase the serum concentration of Rosuvastatin. Management: Start at the lowest rosuvastatin dose and monitor for toxicity. See full drug interaction monograph for details. Consider therapy modification
Rupatadine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Rupatadine. Avoid combination
Ruxolitinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Ruxolitinib. Management: This combination should be avoided under some circumstances. See monograph for details. Consider therapy modification
Salmeterol: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Salmeterol. Avoid combination
Saquinavir: May increase the serum concentration of Atazanavir. Atazanavir may increase the serum concentration of Saquinavir. Avoid combination
Sarilumab: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy
SAXagliptin: CYP3A4 Inhibitors (Strong) may increase the serum concentration of SAXagliptin. Management: Limit the saxagliptin dose to 2.5 mg daily when combined with strong CYP3A4 inhibitors. When using the saxagliptin combination products saxagliptin/dapagliflozin or saxagliptin/dapagliflozin/metformin, avoid use with strong CYP3A4 inhibitors. Consider therapy modification
Sibutramine: CYP3A4 Inhibitors (Strong) may increase serum concentrations of the active metabolite(s) of Sibutramine. CYP3A4 Inhibitors (Strong) may increase the serum concentration of Sibutramine. Monitor therapy
Sildenafil: Protease Inhibitors may increase the serum concentration of Sildenafil. Management: Erectile dysfunction: sildenafil max = 25 mg/48 hrs with ritonavir, atazanavir, or darunavir; starting dose = 25 mg with other protease inhibitors (adult doses). Contraindicated if sildenafil being used for pulmonary arterial hypertension. Consider therapy modification
Sildenafil: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Sildenafil. Management: Use of sildenafil for pulmonary hypertension should be avoided with strong CYP3A4 inhibitors. When used for erectile dysfunction, starting adult dose should be reduced to 25 mg. Maximum adult dose with ritonavir or cobicistat is 25 mg per 48 hours. Consider therapy modification
Silodosin: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Silodosin. Avoid combination
Siltuximab: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy
Simeprevir: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Simeprevir. Avoid combination
Simeprevir: Protease Inhibitors may increase the serum concentration of Simeprevir. Simeprevir may increase the serum concentration of Protease Inhibitors. Avoid combination
Simvastatin: Protease Inhibitors may increase the serum concentration of Simvastatin. Avoid combination
Simvastatin: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Simvastatin. Avoid combination
Sirolimus: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Sirolimus. Management: Consider avoiding concurrent use of sirolimus with strong CYP3A4 inhibitors in order to minimize the risk for sirolimus toxicity. Concomitant use of sirolimus and voriconazole or posaconazole is contraindicated. Consider therapy modification
Solifenacin: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Solifenacin. Management: Limit solifenacin doses to 5 mg daily when combined with strong CYP3A4 inhibitors. Consider therapy modification
Sonidegib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Sonidegib. Avoid combination
SORAfenib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of SORAfenib. Monitor therapy
St John's Wort: May decrease the serum concentration of Atazanavir. Avoid combination
Stiripentol: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Management: Use of stiripentol with CYP3A4 substrates that are considered to have a narrow therapeutic index should be avoided due to the increased risk for adverse effects and toxicity. Any CYP3A4 substrate used with stiripentol requires closer monitoring. Consider therapy modification
SUFentanil: CYP3A4 Inhibitors (Strong) may increase the serum concentration of SUFentanil. Management: If a strong CYP3A4 inhibitor is initiated in a patient on sufentanil, consider a sufentanil dose reduction and monitor for increased sufentanil effects and toxicities (eg, respiratory depression). Consider therapy modification
SUNItinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of SUNItinib. Management: Avoid when possible. If such a combination cannot be avoided, sunitinib dose decreases are recommended, and vary by indication. See full monograph for details. Consider therapy modification
Suvorexant: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Suvorexant. Avoid combination
Tacrolimus (Systemic): Protease Inhibitors may decrease the metabolism of Tacrolimus (Systemic). Consider therapy modification
Tacrolimus (Systemic): CYP3A4 Inhibitors (Strong) may increase the serum concentration of Tacrolimus (Systemic). Management: Monitor clinical tacrolimus response closely and frequently monitor tacrolimus serum concentrations with concurrent use of any strong CYP3A4 inhibitor. Tacrolimus dose reductions and/or prolongation of the dosing interval will likely be required. Consider therapy modification
Tacrolimus (Topical): Protease Inhibitors may decrease the metabolism of Tacrolimus (Topical). Monitor therapy
Tadalafil: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Tadalafil. Management: Recommendations regarding use of tadalafil in patients also receiving strong CYP3A4 inhibitors may vary based on indication and/or international labeling. Consult appropriate product labeling. Consider therapy modification
Talazoparib: BCRP/ABCG2 Inhibitors may increase the serum concentration of Talazoparib. Monitor therapy
Tamsulosin: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Tamsulosin. Avoid combination
Tasimelteon: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Tasimelteon. Monitor therapy
Tazemetostat: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Tazemetostat. Avoid combination
Temsirolimus: Protease Inhibitors may enhance the adverse/toxic effect of Temsirolimus. Levels of sirolimus, the active metabolite, may be increased, likely due to inhibition of CYP-mediated metabolism. Consider therapy modification
Temsirolimus: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Temsirolimus. Management: Avoid concomitant use of temsirolimus and strong CYP3A4 inhibitors whenever possible. If combined, decrease temsirolimus dose to 12.5 mg per week and monitor patients for increased temsirolimus effects and toxicities. Consider therapy modification
Tenofovir Disoproxil Fumarate: May decrease the serum concentration of Atazanavir. Atazanavir may increase the serum concentration of Tenofovir Disoproxil Fumarate. Management: Must use boosted atazanavir in adults; give combo (atazanavir/ritonavir or atazanavir/cobicistat with tenofovir) as a single daily dose with food. Pediatric patients, pregnant patients, and users of H2-blockers require other dose changes. Consider therapy modification
Terfenadine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Terfenadine. Management: Drugs listed as exceptions to this monograph are discussed in further detail in separate drug interaction monographs. Avoid combination
Tetrahydrocannabinol: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Tetrahydrocannabinol. Monitor therapy
Tetrahydrocannabinol and Cannabidiol: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Tetrahydrocannabinol and Cannabidiol. Monitor therapy
Tezacaftor and Ivacaftor: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Tezacaftor and Ivacaftor. Management: When combined with strong CYP3A4 inhibitors, tezacaftor/ivacaftor should be administered in the morning, twice a week, approximately 3 to 4 days apart. No evening doses of ivacaftor alone should be administered. Consider therapy modification
Thiotepa: CYP3A4 Inhibitors (Strong) may decrease serum concentrations of the active metabolite(s) of Thiotepa. CYP3A4 Inhibitors (Strong) may increase the serum concentration of Thiotepa. Management: Thiotepa prescribing information recommends avoiding concomitant use of thiotepa and strong CYP3A4 inhibitors. If concomitant use is unavoidable, monitor for adverse effects and decreased efficacy. Consider therapy modification
Ticagrelor: CYP3A4 Inhibitors (Strong) may decrease serum concentrations of the active metabolite(s) of Ticagrelor. CYP3A4 Inhibitors (Strong) may increase the serum concentration of Ticagrelor. Avoid combination
Tipranavir: May decrease the serum concentration of Protease Inhibitors. Avoid combination
Tocilizumab: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy
Tofacitinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Tofacitinib. Management: Tofacitinib dose reductions are recommended when combined with strong CYP3A4 inhibitors. Recommended dose adjustments vary by tofacitinib formulation and therapeutic indication. See full monograph for details. Consider therapy modification
Tolterodine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Tolterodine. Management: The maximum recommended adult dose of tolterodine is 2 mg/day when used together with a strong CYP3A4 inhibitor. Consider therapy modification
Tolvaptan: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Tolvaptan. Avoid combination
Topotecan: BCRP/ABCG2 Inhibitors may increase the serum concentration of Topotecan. Avoid combination
Toremifene: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Toremifene. Management: Use of toremifene with strong CYP3A4 inhibitors should be avoided if possible. If coadministration is necessary, monitor for increased toremifene toxicities, including QTc interval prolongation. Exceptions are discussed in separate monograph. Consider therapy modification
Trabectedin: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Trabectedin. Avoid combination
TraMADol: CYP3A4 Inhibitors (Strong) may increase the serum concentration of TraMADol. Monitor therapy
TraZODone: CYP3A4 Inhibitors (Strong) may increase the serum concentration of TraZODone. Management: Consider the use of a lower trazodone dose and monitor for increased trazodone effects (eg, sedation, QTc prolongation) if combined with strong CYP3A4 inhibitors. Consider therapy modification
Triazolam: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Triazolam. Avoid combination
Tricyclic Antidepressants: Protease Inhibitors may increase the serum concentration of Tricyclic Antidepressants. Monitor therapy
Ubrogepant: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Ubrogepant. Avoid combination
Udenafil: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Udenafil. Avoid combination
Ulipristal: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Ulipristal. Management: This is specific for when ulipristal is being used for signs/symptoms of uterine fibroids (Canadian indication). When ulipristal is used as an emergency contraceptive, patients receiving this combo should be monitored for ulipristal toxicity. Avoid combination
Upadacitinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Upadacitinib. Monitor therapy
Valbenazine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Valbenazine. Management: Reduce the valbenazine dose to 40 mg daily when combined with strong CYP3A4 inhibitors. Consider therapy modification
Valproate Products: Protease Inhibitors may decrease the serum concentration of Valproate Products. Monitor therapy
Vardenafil: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Vardenafil. Management: Recommendations regarding concomitant use of vardenafil with strong CYP3A4 inhibitors may vary depending on brand name (e.g., Levitra, Staxyn) or by international labeling. See full drug interaction monograph for details. Consider therapy modification
Vemurafenib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Vemurafenib. Management: Avoid concurrent use of vemurafenib with strong CYP3A4 inhibitors when possible. Consider use of an alternative that is not a strong inhibitor of CYP3A4 as clinically appropriate. Consider therapy modification
Venetoclax: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Venetoclax. Management: This combination is contraindicated during venetoclax initiation and ramp-up in patients with CLL/SLL. Reduced venetoclax doses are required during ramp-up for patients with AML, and reduced doses are required for all patients during maintenance therapy. Consider therapy modification
Vilanterol: May increase the serum concentration of CYP3A4 Inhibitors (Strong). Monitor therapy
Vilazodone: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Vilazodone. Management: Limit maximum adult vilazodone dose to 20 mg daily in patients receiving strong CYP3A4 inhibitors. The original vilazodone dose can be resumed following discontinuation of the strong CYP3A4 inhibitor. Consider therapy modification
VinCRIStine (Liposomal): CYP3A4 Inhibitors (Strong) may increase the serum concentration of VinCRIStine (Liposomal). Avoid combination
Vindesine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Vindesine. Monitor therapy
Vinflunine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Vinflunine. Avoid combination
Vinorelbine: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Vinorelbine. Monitor therapy
Vorapaxar: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Vorapaxar. Avoid combination
Voriconazole: Atazanavir may decrease the serum concentration of Voriconazole. Atazanavir may increase the serum concentration of Voriconazole. Voriconazole may decrease the serum concentration of Atazanavir. Management: Voriconazole should not be used in a patient who is being treated with ritonavir-boosted atazanavir unless the benefits of the combination outweigh the potential risks. Extra monitoring for both loss of effectiveness and toxicity is warranted. Avoid combination
Voxelotor: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Voxelotor. Management: Avoid concomitant use of voxelotor and strong CYP3A4 inhibitors. If concomitant use is unavoidable, reduce the voxelotor dose to 1,000 mg once daily. Consider therapy modification
Voxilaprevir: Atazanavir may increase the serum concentration of Voxilaprevir. Avoid combination
Warfarin: Atazanavir may increase the serum concentration of Warfarin. Monitor therapy
Zanubrutinib: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Zanubrutinib. Management: Decrease the zanubrutinib dose to 80 mg once daily during coadministration with a strong CYP3A4 inhibitor. Further dose adjustments may be required for zanubrutinib toxicities, refer to prescribing information for details. Consider therapy modification
Zidovudine: Protease Inhibitors may decrease the serum concentration of Zidovudine. Monitor therapy
Zolpidem: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Zolpidem. Monitor therapy
Zopiclone: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Zopiclone. Management: The initial starting adult dose of zopiclone should not exceed 3.75 mg if combined with a strong CYP3A4 inhibitor. Monitor patients for signs and symptoms of zopiclone toxicity if these agents are combined. Consider therapy modification
Zuclopenthixol: CYP3A4 Inhibitors (Strong) may increase the serum concentration of Zuclopenthixol. Management: Consider zuclopenthixol dosage reduction with concomitant use of a strong CYP3A4 inhibitor (eg, ketoconazole) in poor CYP2D6 metabolizers or with strong CYP2D6 inhibitors (eg, paroxetine). Monitor for increased zuclopenthixol levels/toxicity. Consider therapy modification
Adverse Reactions
Includes data from both treatment-naive and treatment-experienced patients. Unless otherwise noted, frequency of adverse events is as reported in adults receiving combination antiretroviral therapy.
>10%:
Dermatologic: Skin rash (adults 3% to 21%; median onset: 7 weeks; children 14%)
Endocrine & metabolic: Increased serum cholesterol (≥240 mg/dL: 6% to 25%), increased amylase (adults: >2 x ULN: ≤14%)
Gastrointestinal: Nausea (3% to 14%)
Hepatic: Increased serum bilirubin (≥2.6 x ULN: adults 35% to 49%; children 16%), jaundice (children 13% to 15%; adults 5% to 9%)
Neuromuscular & skeletal: Increased creatine phosphokinase (>5 times ULN: 6% to 11%)
Respiratory: Cough (children 21%)
Miscellaneous: Fever (children 18% to 19 %; adults 2%)
1% to 10%:
Cardiovascular: Peripheral edema (children 7%), first degree atrioventricular block (6%), second degree atrioventricular block (children ≤2%; adults [rare])
Central nervous system: Headache (adults 1% to 6%; children 7% to 8%), peripheral neuropathy (<1% to 4%), insomnia (<1% to 3%), depression (2%), dizziness (<1% to 2%)
Endocrine & metabolic: Increased serum triglycerides (≥751 mg/dL: <1% to 8%), hyperglycemia (≥251 mg/dL: 5%), hypoglycemia (children: grades 3/4: 4%)
Gastrointestinal: Vomiting (children 8% to 12%; adults 3% to 4%), diarrhea (children 8% to 9%; adults 1% to 3%), increased serum lipase (adults: >2 x ULN: ≤5%), abdominal pain (4%)
Hematologic & oncologic: Decreased neutrophils (<750 cells/mm3: 3% to 7%), decreased hemoglobin (<8.0 g/dL: <1% to 5%), decreased platelet count (<50,000 cells/mm3: 2%)
Hepatic: Increased serum ALT (adults and children: >5 x ULN: 3% to 9%; 10% to 25% in adult patients co-infected with hepatitis B and/or C), increased serum AST (>5 times ULN: 2% to 7%; 9% to 10% in patients co-infected with hepatitis B and/or C)
Neuromuscular & skeletal: Myalgia (4%), limb pain (children 6%)
Respiratory: Nasal congestion (children 6%), oropharyngeal pain (children 6%), rhinorrhea (children 6%), wheezing (children 6%)
Postmarketing and/or case reports: Alopecia, angioedema, arthralgia, cholecystitis, cholelithiasis, cholestasis, chronic renal failure, complete atrioventricular block (rare), diabetes mellitus, DRESS syndrome, edema, erythema multiforme, granulomatous interstitial nephritis, hepatic abnormality, immune reconstitution syndrome, interstitial nephritis, left bundle branch block, maculopapular rash, nephrolithiasis, pancreatitis, prolongation P-R interval on ECG, prolonged Q-T interval on ECG, pruritus, Stevens-Johnson syndrome, torsades de pointes
Warnings/Precautions
Concerns related to adverse effects:
- Elevated bilirubin: Asymptomatic elevations in bilirubin (unconjugated) occur commonly during therapy and are reversible upon discontinuation of treatment. Consider alternative therapy if jaundice or scleral icterus associated with bilirubin elevations present cosmetic concerns. Evaluate alternative etiologies if transaminase elevations also occur (dose reduction is not recommended because long-term efficacy has not been established).
- Fat redistribution: May cause redistribution/accumulation of fat (eg, central obesity, buffalo hump, peripheral wasting, facial wasting, breast enlargement, cushingoid appearance).
- Hypersensitivity reactions: Protease inhibitors have been associated with a variety of hypersensitivity events (some severe), including rash, anaphylaxis (rare), angioedema, bronchospasm, erythema multiforme, Stevens-Johnson syndrome (rare), and/or toxic skin eruptions (including DRESS [drug rash, eosinophilia and systemic symptoms] syndrome). It is generally recommended to discontinue treatment if severe rash or moderate symptoms accompanied by other systemic symptoms occur.
- Immune reconstitution syndrome: Patients may develop immune reconstitution syndrome resulting in the occurrence of an inflammatory response to an indolent or residual opportunistic infection during initial HIV treatment or activation of autoimmune disorders (eg, Graves disease, polymyositis, Guillain-Barré syndrome) later in therapy; further evaluation and treatment may be required.
- Nephrolithiasis/cholelithiasis: Cases have been reported in postmarketing surveillance; some associated with complications and/or requiring hospitalization. Consider temporary or permanent discontinuation of therapy if symptoms develop.
Disease-related concerns:
- Conduction abnormalities: May prolong PR interval; ECG monitoring should be considered in patients with preexisting conduction abnormalities or with medications which prolong AV conduction (dosage adjustment required with some agents); rare cases of second-degree AV block have been reported.
- Diabetes: Changes in glucose tolerance, hyperglycemia, exacerbation of diabetes, DKA, and new-onset diabetes mellitus have been reported in patients receiving protease inhibitors.
- Hemophilia A or B: Use with caution in patients with hemophilia A or B; increased bleeding during protease inhibitor therapy has been reported.
- Hepatic impairment: Protease inhibitors may cause hepatitis and/or exacerbate preexisting hepatic dysfunction; use with caution in patients with transaminase elevations prior to therapy or underlying hepatic disease, such as hepatitis B or C or cirrhosis; monitor closely at baseline and during treatment. Not recommended in patients with severe hepatic impairment. In combination with ritonavir, is not recommended in patients with any degree of hepatic impairment.
- Renal impairment: Cases of chronic kidney disease, including granulomatous interstitial nephritis, have been reported in postmarketing surveillance; consider alternative therapy in patients at high risk for renal impairment or with preexisting renal disease. Renal laboratory testing (serum creatinine, estimated CrCl, and urinalysis with microscopic examination) should be performed prior to initiation and throughout treatment. Not recommended for use in treatment-experienced patients with ESRD on hemodialysis. Consider therapy discontinuation in patients with progressive kidney disease.
Concurrent drug therapy issues:
- Drug-drug interactions: Potentially significant interactions may exist, requiring dose or frequency adjustment, additional monitoring, and/or selection of alternative therapy. Consult drug interactions database for more detailed information.
Dosage form specific issues:
- Oral powder: contains phenylalanine; avoid or use with caution in patients with phenylketonuria. Oral powder is not recommended for use in children <5 kg.
Special populations:
- Pediatric: Do not use in children <3 months of age due to potential for kernicterus.
Other warnings/precautions:
- Appropriate use: Do not use atazanavir/ritonavir plus abacavir/lamivudine in adolescent and adult HIV-1 patients with a pre-ART HIV RNA >100,000 copies/mL (HHS [adult] 2016).
Monitoring Parameters
Viral load, CD4, serum glucose; liver function tests (prior to initiation and as clinically indicated in patients with existing liver disease), bilirubin (as clinically indicated); drug levels (with certain concomitant medications), ECG monitoring in patients with preexisting prolonged PR interval or with concurrent AV nodal blocking drugs; serum creatinine, estimated CrCL, and urinalysis with microscopic examination (prior to initiation and as clinically indicated).
Pregnancy
Pregnancy Considerations
Atazanavir has a low level of transfer across the human placenta with cord blood concentrations reported as 13% to 21% of maternal serum concentrations at delivery.
An increased risk of teratogenic effects has not been observed based on information collected by the antiretroviral pregnancy registry. Maternal antiretroviral therapy (ART) may be associated with adverse pregnancy outcomes including preterm delivery, stillbirth, low birth weight, and small for gestational age infants. Actual risks may be influenced by maternal factors such as disease severity, gestational age at initiation of therapy, and specific ART regimen, therefore close fetal monitoring is recommended. Because there is clear benefit to appropriate treatment, maternal ART should not be withheld due to concerns for adverse neonatal outcomes. Long-term follow-up is recommended for all infants exposed to antiretroviral medications; children without HIV but who were exposed to ART in utero and develop significant organ system abnormalities of unknown etiology (particularly of the CNS or heart) should be evaluated for potential mitochondrial dysfunction. Hyperbilirubinemia or hypoglycemia may occur in neonates following in utero exposure to atazanavir, although data are conflicting (monitor). Hyperglycemia, new onset of diabetes mellitus, or diabetic ketoacidosis have been reported with protease inhibitors; it is not clear if pregnancy increases this risk. Consider performing the standard glucose screening test earlier in pregnancy in women who initiated protease inhibitor therapy prior to conception.
Use of unboosted atazanavir is not recommended during pregnancy. The Health and Human Services (HHS) perinatal HIV guidelines consider atazanavir (when combined with low-dose ritonavir boosting) a preferred protease inhibitor for pregnant females living with HIV who are antiretroviral-naive (initial therapy), who have had ART therapy in the past but are restarting, who require a new ART regimen (due to poor tolerance or poor virologic response of current regimen), and who are not yet pregnant but are trying to conceive. In addition, females who become pregnant while taking atazanavir may continue if viral suppression is effective and the regimen is well tolerated. Atazanavir (when combined with low-dose cobicistat boosting) is not recommended for use during pregnancy or women who are planning a pregnancy. If pregnancy occurs during therapy, consideration should be given to changing to a more effective regimen. If continued, close monitoring, including more frequent therapeutic drug monitoring if available, is recommended.
Atazanavir is not recommended in treatment-experienced pregnant females taking both H2-receptor blockers and tenofovir disoproxil fumarate. Pharmacokinetic studies suggest that standard dosing during pregnancy may provide decreased plasma concentrations and some experts recommend increased doses during the second and third trimesters. However, the manufacturer notes that dose adjustment is not required unless using concomitant H2-receptor blockers or tenofovir disoproxil fumarate in antiretroviral-experienced pregnant females. Therapeutic drug monitoring may be useful.
In general, ART is recommended for all pregnant females living with HIV to keep the viral load below the limit of detection and reduce the risk of perinatal transmission. Therapy should be individualized following a discussion of the potential risks and benefits of treatment during pregnancy. Monitoring of pregnant females is more frequent than in non-pregnant adults. ART should be continued postpartum for all females living with HIV and can be modified after delivery.
Health care providers are encouraged to enroll pregnant females exposed to antiretroviral medications as early in pregnancy as possible in the Antiretroviral Pregnancy Registry (1-800-258-4263 or http://www.APRegistry.com). Health care providers caring for pregnant females living with HIV and their infants may contact the National Perinatal HIV Hotline (888-448-8765) for clinical consultation (HHS [perinatal] 2019).
Patient Education
What is this drug used for?
- It is used to treat HIV infection.
Frequently reported side effects of this drug
- Headache
- Diarrhea
- Stuffy nose
- Sore throat
- Abdominal pain
- Nausea
- Vomiting
- Trouble sleeping
Other side effects of this drug: Talk with your doctor right away if you have any of these signs of:
- Liver problems like dark urine, fatigue, lack of appetite, nausea, abdominal pain, light-colored stools, vomiting, or yellow skin.
- High blood sugar like confusion, fatigue, increased thirst, increased hunger, passing a lot of urine, flushing, fast breathing, or breath that smells like fruit.
- Gallstones like pain in the upper right abdominal area, right shoulder area, or between the shoulder blades; yellow skin; or fever with chills.
- Kidney problems like unable to pass urine, blood in the urine, change in amount of urine passed, or weight gain.
- Abnormal heartbeat
- Dizziness
- Passing out
- Joint pain
- Muscle pain
- Painful urination
- Kidney stone like back pain, abdominal pain, or blood in the urine.
- Burning or numbness feeling
- Depression
- Bruising
- Bleeding
- Change in body fat
- Yellow skin
- Swelling of arms or legs
- Stevens-Johnson syndrome/toxic epidermal necrolysis like red, swollen, blistered, or peeling skin (with or without fever); red or irritated eyes; or sores in mouth, throat, nose, or eyes.
- Infection
- Signs of a significant reaction like wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat.
Note: This is not a comprehensive list of all side effects. Talk to your doctor if you have questions.
Consumer Information Use and Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only the healthcare provider has the knowledge and training to decide which medicines are right for a specific patient. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this medicine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not specific medical advice and does not replace information you receive from the healthcare provider. You must talk with the healthcare provider for complete information about the risks and benefits of using this medicine.
