Drug Interactions between amiodarone and Torisel
This report displays the potential drug interactions for the following 2 drugs:
- amiodarone
- Torisel (temsirolimus)
Interactions between your drugs
amiodarone temsirolimus
Applies to: amiodarone and Torisel (temsirolimus)
MONITOR: Coadministration of temsirolimus with inhibitors of CYP450 3A4 may increase the plasma concentrations of sirolimus, a major active metabolite of temsirolimus and known substrate of CYP450 3A4. According to the product labeling, administration of temsirolimus in combination with the potent CYP450 3A4 inhibitor ketoconazole resulted in a 2.2-fold and 3.1-fold increase in sirolimus peak plasma concentration (Cmax) and systemic exposure (AUC), respectively, compared to administration of temsirolimus alone. No significant effect on the pharmacokinetics of temsirolimus was reported.
MANAGEMENT: Caution is advised if temsirolimus is prescribed in combination with CYP450 3A4 inhibitors. Pharmacologic response to temsirolimus should be monitored more closely whenever a CYP450 3A4 inhibitor is added to or withdrawn from therapy, and the temsirolimus dosage adjusted as necessary. Patients should be advised to contact their physician if they experience increased adverse effects of temsirolimus such as hyperglycemia (e.g., excessive thirst; increased volume and/or frequency of urination), infections, fever, dyspnea, abdominal pain, diarrhea, and bloody stools.
References (1)
- (2007) "Product Information. Torisel (temsirolimus)." Wyeth-Ayerst Laboratories
Drug and food interactions
amiodarone food
Applies to: amiodarone
GENERALLY AVOID: Grapefruit juice may significantly increase the plasma concentrations of orally administered amiodarone. The proposed mechanism is inhibition of CYP450 3A4-mediated first-pass metabolism in the gut wall by certain compounds present in grapefruits. In 11 nonsmoking, healthy volunteers, grapefruit juice (300 mL with drug administration, then 3 hours and 9 hours later) increased the mean peak plasma concentration (Cmax) and area under the concentration-time curve (AUC) of amiodarone (17 mg/kg single dose) by 84% and 50%, respectively, compared to water. Formation of the pharmacologically active metabolite, N-desethylamiodarone (N-DEA), was completely inhibited. Clinically, this interaction can lead to altered efficacy of amiodarone, since antiarrhythmic properties of amiodarone and N-DEA appear to differ. In the study, mean increases in PR and QTc intervals of 17.9% and 11.3%, respectively, were observed 6 hours postdose with water, while increases of 10.2% and 3.3%, respectively, were observed after administration with grapefruit juice.
ADJUST DOSING INTERVAL: Food increases the rate and extent of absorption of amiodarone. The mechanism appears to involve the effect of food-induced physiologic changes on drug release from its formulation. In 30 healthy volunteers, administration of a single 600 mg dose of amiodarone following a high-fat meal resulted in a Cmax and AUC that were 3.8 and 2.4 times the respective values under fasting conditions. The time to reach peak plasma concentration (Tmax) was decreased by 37%, indicating an increased rate of absorption. Mean Cmax and AUC for the active metabolite, N-DEA, also increased by 32% and 55%, respectively, but there was no change in the Tmax.
MANAGEMENT: Patients treated with oral amiodarone should avoid consumption of grapefruits and grapefruit juice. In addition, oral amiodarone should be administered consistently with regard to meals.
References (3)
- (2002) "Product Information. Cordarone (amiodarone)." Wyeth-Ayerst Laboratories
- Libersa CC, Brique SA, Motte KB, et al. (2000) "Dramatic inhibition of amiodarone metabolism induced by grapefruit juice." Br J Clin Pharmacol, 49, p. 373-8
- Meng X, Mojaverian P, Doedee M, Lin E, Weinryb I, Chiang ST, Kowey PR (2001) "Bioavailability of Amiodarone tablets administered with and without food in healthy subjects." Am J Cardiol, 87, p. 432-5
temsirolimus food
Applies to: Torisel (temsirolimus)
GENERALLY AVOID: Coadministration of temsirolimus with grapefruit juice may increase the plasma concentrations of sirolimus, a major active metabolite of temsirolimus and known substrate of CYP450 3A4. The proposed mechanism is inhibition of CYP450 3A4-mediated metabolism by certain compounds present in grapefruits.
MANAGEMENT: Patients treated with temsirolimus should preferably avoid the consumption of grapefruit or grapefruit juice.
References (1)
- (2007) "Product Information. Torisel (temsirolimus)." Wyeth-Ayerst Laboratories
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.
See also
Drug Interaction Classification
Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit. | |
Moderately clinically significant. Usually avoid combinations; use it only under special circumstances. | |
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. | |
No interaction information available. |
Further information
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