7 Interactions found for:
Drug Interactions
No drug interactions were found for selected drugs: Norvasc, gabapentin.
This does not necessarily mean no interactions exist. Always consult your healthcare provider.
Drug and Food Interactions
Moderate
Gabapentin
+ Food
The following applies to the ingredients: Gabapentin
GENERALLY AVOID: Alcohol may potentiate some of the pharmacologic effects of CNS-active agents. Use in combination may result in additive central nervous system depression and/or impairment of judgment, thinking, and psychomotor skills.
MANAGEMENT: Patients receiving CNS-active agents should be warned of this interaction and advised to avoid or limit consumption of alcohol. Ambulatory patients should be counseled to avoid hazardous activities requiring complete mental alertness and motor coordination until they know how these agents affect them, and to notify their physician if they experience excessive or prolonged CNS effects that interfere with their normal activities.
References
- Warrington SJ, Ankier SI, Turner P "Evaluation of possible interactions between ethanol and trazodone or amitriptyline." Neuropsychobiology 15 (1986): 31-7
- Gilman AG, eds., Nies AS, Rall TW, Taylor P "Goodman and Gilman's the Pharmacological Basis of Therapeutics." New York, NY: Pergamon Press Inc. (1990):
- "Product Information. Fycompa (perampanel)." Eisai Inc (2012):
- "Product Information. Rexulti (brexpiprazole)." Otsuka American Pharmaceuticals Inc (2015):
Moderate
Norvasc
+ Food
The following applies to the ingredients: Amlodipine (found in Norvasc)
MONITOR: Many psychotherapeutic and CNS-active agents (e.g., anxiolytics, sedatives, hypnotics, antidepressants, antipsychotics, opioids, alcohol, muscle relaxants) exhibit hypotensive effects, especially during initiation of therapy and dose escalation. Coadministration with antihypertensives and other hypotensive agents, in particular vasodilators and alpha-blockers, may result in additive effects on blood pressure and orthostasis.
MANAGEMENT: Caution and close monitoring for development of hypotension is advised during coadministration of these agents. Some authorities recommend avoiding alcohol in patients receiving vasodilating antihypertensive drugs. Patients should be advised to avoid rising abruptly from a sitting or recumbent position and to notify their physician if they experience dizziness, lightheadedness, syncope, orthostasis, or tachycardia.
References
- Sternbach H "Fluoxetine-associated potentiation of calcium-channel blockers." J Clin Psychopharmacol 11 (1991): 390-1
- Shook TL, Kirshenbaum JM, Hundley RF, Shorey JM, Lamas GA "Ethanol intoxication complicating intravenous nitroglycerin therapy." Ann Intern Med 101 (1984): 498-9
- Feder R "Bradycardia and syncope induced by fluoxetine." J Clin Psychiatry 52 (1991): 139
- Ellison JM, Milofsky JE, Ely E "Fluoxetine-induced bradycardia and syncope in two patients." J Clin Psychiatry 51 (1990): 385-6
- Rodriguez de la Torre B, Dreher J, Malevany I, et al. "Serum levels and cardiovascular effects of tricyclic antidepressants and selective serotonin reuptake inhibitors in depressed patients." Ther Drug Monit 23 (2001): 435-40
- Cerner Multum, Inc. "Australian Product Information." O 0
- Pacher P, Kecskemeti V "Cardiovascular side effects of new antidepressants and antipsychotics: new drugs, old concerns?" Curr Pharm Des 10 (2004): 2463-75
- Andrews C, Pinner G "Postural hypotension induced by paroxetine." BMJ 316 (1998): 595
The following applies to the ingredients: Amlodipine (found in Norvasc)
MONITOR: Calcium-containing products may decrease the effectiveness of calcium channel blockers by saturating calcium channels with calcium. Calcium chloride has been used to manage acute severe verapamil toxicity.
MANAGEMENT: Management consists of monitoring the effectiveness of calcium channel blocker therapy during coadministration with calcium products.
References
- Henry M, Kay MM, Viccellio P "Cardiogenic shock associated with calcium-channel and beta blockers: reversal with intravenous calcium chloride." Am J Emerg Med 3 (1985): 334-6
- Moller IW "Cardiac arrest following intravenous verapamil combined with halothane anaesthesia." Br J Anaesth 59 (1987): 522-6
- Oszko MA, Klutman NE "Use of calcium salts during cardiopulmonary resuscitation for reversing verapamil-associated hypotension." Clin Pharm 6 (1987): 448-9
- Schoen MD, Parker RB, Hoon TJ, et al. "Evaluation of the pharmacokinetics and electrocardiographic effects of intravenous verapamil with intravenous calcium chloride pretreatment in normal subjects." Am J Cardiol 67 (1991): 300-4
- O'Quinn SV, Wohns DH, Clarke S, Koch G, Patterson JH, Adams KF "Influence of calcium on the hemodynamic and anti-ischemic effects of nifedipine observed during treadmill exercise testing." Pharmacotherapy 10 (1990): 247
- Woie L, Storstein L "Successful treatment of suicidal verapamil poisoning with calcium gluconate." Eur Heart J 2 (1981): 239-42
- Morris DL, Goldschlager N "Calcium infusion for reversal of adverse effects of intravenous verapamil." JAMA 249 (1983): 3212-3
- Guadagnino V, Greengart A, Hollander G, Solar M, Shani J, Lichstein E "Treatment of severe left ventricular dysfunction with calcium chloride in patients receiving verapamil." J Clin Pharmacol 27 (1987): 407-9
- Luscher TF, Noll G, Sturmer T, Huser B, Wenk M "Calcium gluconate in severe verapamil intoxication." N Engl J Med 330 (1994): 718-20
- Bar-Or D, Gasiel Y "Calcium and calciferol antagonise effect of verapamil in atrial fibrillation." Br Med J (Clin Res Ed) 282 (1981): 1585-6
- Lipman J, Jardine I, Roos C, Dreosti L "Intravenous calcium chloride as an antidote to verapamil-induced hypotension." Intensive Care Med 8 (1982): 55-7
- McMillan R "Management of acute severe verapamil intoxication." J Emerg Med 6 (1988): 193-6
- Perkins CM "Serious verapamil poisoning: treatment with intravenous calcium gluconate." Br Med J 2 (1978): 1127
- Moroni F, Mannaioni PF, Dolara A, Ciaccheri M "Calcium gluconate and hypertonic sodium chloride in a case of massive verapamil poisoning." Clin Toxicol 17 (1980): 395-400
Minor
Norvasc
+ Food
The following applies to the ingredients: Amlodipine (found in Norvasc)
The consumption of grapefruit juice may slightly increase plasma concentrations of amlodipine. The mechanism is inhibition of CYP450 3A4-mediated first-pass metabolism in the gut wall by certain compounds present in grapefruits. Data have been conflicting and the clinical significance is unknown. Monitoring for calcium channel blocker adverse effects (e.g., headache, hypotension, syncope, tachycardia, edema) is recommended.
References
- Bailey DG, Arnold JMO, Spence JD "Grapefruit juice and drugs - how significant is the interaction." Clin Pharmacokinet 26 (1994): 91-8
- Josefsson M, Zackrisson AL, Ahlner J "Effect of grapefruit juice on the pharmacokinetics of amlodipine in healthy volunteers." Eur J Clin Pharmacol 51 (1996): 189-93
- Bailey DG, Malcolm J, Arnold O, Spence JD "Grapefruit juice-drug interactions." Br J Clin Pharmacol 46 (1998): 101-10
- Vincent J, Harris SI, Foulds G, Dogolo LC, Willavize S, Friedman HL "Lack of effect of grapefruit juice on the pharmacokinetics and pharmacodynamics of amlodipine." Br J Clin Pharmacol 50 (2000): 455-63
- Josefsson M, Ahlner J "Amlodipine and grapefruit juice." Br J Clin Pharmacol 53 (2002): 405; discussion 406
- Kane GC, Lipsky JJ "Drug-grapefruit juice interactions." Mayo Clin Proc 75 (2000): 933-42
Drug and Pregnancy Interactions
Major
Norvasc
+ Pregnancy
The following applies to the ingredients: Amlodipine (found in Norvasc)
This drug should be used during pregnancy only if the benefit outweighs the risk to the fetus (AU, US)
Use is contraindicated (UK)
AU TGA pregnancy category: C
US FDA pregnancy category: C
Comments:
-Use of adequate methods of contraception should be encouraged.
-If this drug is used during pregnancy, or if the patient becomes pregnant while taking this drug, the patient should be apprised of the potential harm to the fetus.
Animal studies have shown significantly decreased litter size, increased intrauterine deaths and prolongation of gestation and duration of labor when this drug was given before mating, throughout mating, and during gestation. There are no controlled data in human pregnancy.
Reversible biochemical changes in the head of spermatozoa occurred in some patients treated with calcium channel blockers. There are no controlled data for this drug, but animal models have shown adverse effects on male fertility.
AU TGA pregnancy category C: Drugs which, owing to their pharmacological effects, have caused or may be suspected of causing, harmful effects on the human fetus or neonate without causing malformations. These effects may be reversible. Accompanying texts should be consulted for further details.
US FDA pregnancy category C: Animal reproduction studies have shown an adverse effect on the fetus and there are no adequate and well-controlled studies in humans, but potential benefits may warrant use of the drug in pregnant women despite potential risks.
References
- "Product Information. Norvasc (amlodipine)." Pfizer U.S. Pharmaceuticals PROD (2002):
- Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0
- Cerner Multum, Inc. "Australian Product Information." O 0
Major
Gabapentin
+ Pregnancy
The following applies to the ingredients: Gabapentin
Benefits should clearly outweigh risks
AU TGA pregnancy category: B3
US FDA pregnancy category: Not assigned
Risk Summary: There are no data on the developmental risks associated with use of this drug in pregnant women; in animal studies, developmental toxicity was observed at doses estimated to be similar or lower than those used clinically.
Comments:
-The risk of having a child with a congenital defect as a result of antiepileptic medication is far outweighed by the dangers to the mother and fetus of uncontrolled epilepsy; folic acid supplementation (5 mg) should be started 4 weeks prior to and continued for 12 weeks after conception.
-Women of childbearing potential should receive counseling on the risk of fetal abnormalities with use of antiepileptic drugs (AEDs) during pregnancy; AEDs should generally be continued during pregnancy utilizing monotherapy at the lowest effective dose as this has been shown to minimize risks of fetal abnormalities compared to combination AED therapy.
-A pregnancy exposure registry is available.
Animal studies have revealed evidence of developmental toxicity (increased fetal skeletal and visceral abnormalities, and increased embryofetal mortality) when administered at doses similar to, or lower than expected clinical doses. In rats, an increased incidence of hydroureter and/or hydronephrosis have been observed in offspring at all doses, the lowest dose being similar to the maximum recommended human dose on a mg/m2 basis. This drug crosses the human placenta. From the limited amount of data in human pregnancy, it is not possible to inform an associated increased risk of congenital malformations because epilepsy itself and the presence of concomitant antiepileptic medicinal products have their own risks. There are no controlled data in human pregnancy.
To provide information regarding the effects of in utero exposure to this drug, pregnant patients should be encouraged to enroll in the North American Antiepileptic Drug (NAAED) Pregnancy Registry. This can be done by calling the toll-free number 1-888-233-2334 and must be done by patients themselves. Information on the registry can also be found at the website http://www.aedpregnancyregistry.org/.
AU TGA pregnancy category B3: Drugs which have been taken by only a limited number of pregnant women and women of childbearing age, without an increase in the frequency of malformation or other direct or indirect harmful effects on the human fetus having been observed. Studies in animals have shown evidence of an increased occurrence of fetal damage, the significance of which is considered uncertain in humans.
US FDA pregnancy category Not Assigned: The US FDA has amended the pregnancy labeling rule for prescription drug products to require labeling that includes a summary of risk, a discussion of the data supporting that summary, and relevant information to help health care providers make prescribing decisions and counsel women about the use of drugs during pregnancy. Pregnancy categories A, B, C, D and X are being phased out.
References
- "Product Information. Neurontin (gabapentin)." Parke-Davis PROD (2001):
- Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0
- Cerner Multum, Inc. "Australian Product Information." O 0
- "Product Information. Horizant (gabapentin)." GlaxoSmithKline (2021):
- "Product Information. Gralise (gabapentin)." Depomed Inc (2021):
Drug and Breastfeeding Interactions
Major
Norvasc
+ Breastfeeding
The following applies to the ingredients: Amlodipine (found in Norvasc)
Use is not recommended and a decision should be made to discontinue breastfeeding or discontinue the drug, taking into account the importance of the drug to the mother (AU, US)
Use is contraindicated (UK)
Excreted into human milk: Yes
Comments:
-The effects in the nursing infant are unknown.
-Infants exposed to this drug should be closely monitored.
References
- "Product Information. Norvasc (amlodipine)." Pfizer U.S. Pharmaceuticals PROD (2002):
- Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0
- Cerner Multum, Inc. "Australian Product Information." O 0
- United States National Library of Medicine "Toxnet. Toxicology Data Network. http://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen?LACT" (2013):
Major
Gabapentin
+ Breastfeeding
The following applies to the ingredients: Gabapentin
Benefits should clearly outweigh risks
Excreted into human milk: Yes
Comments:
-Breastfed infants should be monitored for drowsiness, adequate weight gain, and developmental milestones, especially when used in combination with other anticonvulsant or psychotropic drugs and in younger, exclusively breastfed infants.
-Some authorities suggest discontinuing nursing or discontinuing use of this drug while breastfeeding due to the potential for serious adverse reactions in the breastfed infant.
With maternal doses up to 2.1 g/day, estimated doses for fully breastfed infants are 0.2 to 1.3 mg/kg/day (equivalent to 1.3 to 3.8% of the maternal weight-adjusted dose). An expert panel has deemed this drug is an acceptable choice for refractory restless leg syndrome during lactation. Until more data becomes available, the developmental and health benefits of breastfeeding should be considered along with the mother's clinical need for this drug and any potential adverse effects on the breastfed infant from this drug or from the underlying maternal condition.
References
- "Product Information. Neurontin (gabapentin)." Parke-Davis PROD (2001):
- Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0
- Cerner Multum, Inc. "Australian Product Information." O 0
- United States National Library of Medicine "Toxnet. Toxicology Data Network. http://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen?LACT" (2013):
- "Product Information. Horizant (gabapentin)." GlaxoSmithKline (2021):
- "Product Information. Gralise (gabapentin)." Depomed Inc (2021):
Therapeutic Duplication Warnings
No warnings were found for your selected drugs.Therapeutic duplication warnings are only returned when drugs within the same group exceed the recommended therapeutic duplication maximum.
Switch to: Consumer Interactions
Drug Interaction Classification | |
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These classifications are only a guideline. The relevance of a particular drug interaction to a specific individual is difficult to determine. Always consult your healthcare provider before starting or stopping any medication. |
|
Major | Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit. |
Moderate | Moderately clinically significant. Usually avoid combinations; use it only under special circumstances. |
Minor | Minimally clinically significant. Minimize risk; assess risk and consider an alternative drug, take steps to circumvent the interaction risk and/or institute a monitoring plan. |
Unknown | No interaction information available. |
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