8 Interactions found for:
Drug Interactions
Minor
Hydrochlorothiazide
+ Norvasc
The following applies to the ingredients: Hydrochlorothiazide and Amlodipine (found in Norvasc)
Professional Content
The antihypertensive effect of amlodipine and thiazide diuretics may be additive. Management consists of monitoring blood pressure during coadministration, especially during the first 1 to 3 weeks of therapy.
References
- Kaplan NM "Amlodipine in the treatment of hypertension." Postgrad Med J 67 Suppl 5 (1991): s15-9
Drug and Food Interactions
Moderate
Hydrochlorothiazide
+ Food
The following applies to the ingredients: Hydrochlorothiazide
HydroCHLOROthiazide and ethanol may have additive effects in lowering your blood pressure. You may experience headache, dizziness, lightheadedness, fainting, and/or changes in pulse or heart rate. These side effects are most likely to be seen at the beginning of treatment, following a dose increase, or when treatment is restarted after an interruption. Let your doctor know if you develop these symptoms and they do not go away after a few days or they become troublesome. Avoid driving or operating hazardous machinery until you know how the medications affect you, and use caution when getting up from a sitting or lying position. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.
Moderate
Norvasc
+ Food
The following applies to the ingredients: Amlodipine (found in Norvasc)
AmLODIPine and ethanol may have additive effects in lowering your blood pressure. You may experience headache, dizziness, lightheadedness, fainting, and/or changes in pulse or heart rate. These side effects are most likely to be seen at the beginning of treatment, following a dose increase, or when treatment is restarted after an interruption. Let your doctor know if you develop these symptoms and they do not go away after a few days or they become troublesome. Avoid driving or operating hazardous machinery until you know how the medications affect you, and use caution when getting up from a sitting or lying position. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.
The following applies to the ingredients: Amlodipine (found in Norvasc)
Using amLODIPine together with multivitamin with minerals can decrease the effects of amLODIPine. Talk with your doctor before using amLODIPine and multivitamin with minerals together. You may need a dose adjustment or need your blood pressure checked more often if you take both medications. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.
Minor
Norvasc
+ Food
The following applies to the ingredients: Amlodipine (found in Norvasc)
Professional Content
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)
Professional Content
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
Hydrochlorothiazide
+ Pregnancy
The following applies to the ingredients: Hydrochlorothiazide
Professional Content
The manufacturer recommends that hydrochlorothiazide should be used during pregnancy only if the potential benefit outweighs the potential risk to the fetus.
AU TGA pregnancy category: C
US FDA pregnancy category: B
The routine use of diuretics during pregnancy is not indicated or recommended.
Animal studies have failed to reveal evidence of fetal harm. There are no data from controlled human studies, but retrospective reviews have shown an increased risk of malformations associated with thiazide diuretics. In addition, use of thiazide diuretics during pregnancy has been associated with fetal or neonatal electrolyte abnormalities, jaundice, and/or thrombocytopenia.
The Collaborative Perinatal Project monitored 50,282 mother-child pairs, of whom 233 were exposed to thiazide or related diuretics during the first trimester. An increased risk of malformations was found for thiazide diuretics. Use of thiazides after the first trimester does not seem to carry this risk. Thiazide diuretics may, however pose metabolic risks to the mother and fetus (hyponatremia, hypokalemia, thrombocytopenia, hyperglycemia), and may have a direct effect on smooth muscle, resulting in inhibition of labour.
Data from the U.S. Michigan Medicaid Birth Defects Study has revealed an association between the use of hydrochlorothiazide and congenital abnormalities. This was a retrospective study of 229,101 completed pregnancies between 1985 and 1992, of which 567 were exposed to hydrochlorothiazide at some time during the first trimester, and 1,173 were exposed to the drug at any time during pregnancy. Of the 567 pregnancies, there were 24 total and 7 cardiovascular birth defects (22 and 6 were expected, respectively). There were no observations of cleft palate, spina bifida, limb reduction, or hypospadias. The one instance of polydactyly did not achieve statistical significance. These data are consistent with an association between the use of hydrochlorothiazide and birth defects, although other factors, including underlying disease(s) of the mother are not accounted for.
Cases of neonatal thrombocytopenia associated with antepartum administration of thiazide diuretics have been reported.
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 B: Animal reproduction studies have failed to demonstrate a risk to the fetus and there are no adequate and well-controlled studies in pregnant women.
References
- Heinonen O, Shapiro S; Kaufman DW ed., Slone D "Birth Defects and Drugs in Pregnancy." Littleton, MA: Publishing Sciences Group, Inc. (1977): 297
- Rodriguez SU, Sanford LL, Hiller MC "Neonatal thrombocytopenia associated with ante-partum administration of thiazide drugs." N Engl J Med 270 (1964): 881-4
- Lindheimer MD, Katz AI "Sodiuim and diuretics in pregnancy." N Engl J Med 288 (1973): 891-4
- Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0
- Pharmaceutical Society of Australia "APPGuide online. Australian prescription products guide online. http://www.appco.com.au/appguide/default.asp" (2006):
- Cerner Multum, Inc. "Australian Product Information." O 0
Drug and Breastfeeding Interactions
Major
Hydrochlorothiazide
+ Breastfeeding
The following applies to the ingredients: Hydrochlorothiazide
Professional Content
Manufacturer recommendation: 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.
Excreted into human milk: Yes
According to LactMed this drug has been used without apparent harmful effects in the nursing infant at doses of 50 mg daily or less. Large doses may cause intense diuresis resulting in a decrease in breastmilk production.
References
- "Product Information. HydroDIURIL (hydrochlorothiazide)." Merck & Co., Inc PROD (2002):
- 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
Norvasc
+ Breastfeeding
The following applies to the ingredients: Amlodipine (found in Norvasc)
Professional Content
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):
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: Professional Interactions
| Drug Interaction Classification | |
|---|---|
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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