Skip to main content

Drug Interactions between estropipate and telaprevir

This report displays the potential drug interactions for the following 2 drugs:

Edit list (add/remove drugs)

Interactions between your drugs

Moderate

estropipate telaprevir

Applies to: estropipate and telaprevir

MONITOR: Coadministration with the hepatitis C virus (HCV) NS3/4A protease inhibitors, boceprevir and telaprevir, may decrease the plasma concentrations and efficacy of estrogens used for hormonal replacement therapy. The mechanism involves induction of CYP450 3A4, the isoenzyme primarily responsible for the metabolic clearance of sex hormones. When an oral contraceptive containing drospirenone-ethinyl estradiol (3 mg-0.02 mg daily for 14 days) was given in combination with boceprevir (800 mg three times daily for 7 days), ethinyl estradiol systemic exposure (AUC) decreased by approximately 25%, with no change in the peak plasma concentration (Cmax). In a study of 24 subjects who were administered an oral contraceptive containing ethinyl estradiol-norethindrone (0.035 mg-0.5 mg daily) concomitantly with telaprevir (750 mg every 8 hours) for 21 days, the Cmax and AUC of ethinyl estradiol decreased by 26% and 28%, respectively. In addition, there was a 33% reduction in the trough plasma concentration (Cmin) of ethinyl estradiol.

MANAGEMENT: Dosage adjustments as well as increased clinical and laboratory monitoring for estrogen deficiency should be considered whenever boceprevir or telaprevir is used concomitantly with estrogens used for hormonal replacement therapy.

References (3)
  1. (2011) "Product Information. Victrelis (boceprevir)." Schering-Plough Corporation
  2. (2011) "Product Information. Incivek (telaprevir)." Vertex Pharmaceuticals
  3. Faculty of Sexual & Reproductive Healthcare (2016) "FSRH Clinical Guidance: Drug Interactions with Hormonal Contraception. file:///C:/Users/df033684/Downloads/ceuguidancedruginteractionshormonal.pdf"

Drug and food interactions

Moderate

telaprevir food

Applies to: telaprevir

ADJUST DOSING INTERVAL: Food significantly enhances the oral bioavailability of telaprevir. When given with a meal containing 533 kcal and 21 g fat, telaprevir systemic exposure (AUC) increased by 237% compared to administration under fasting conditions. The type of meal also affects the exposure to telaprevir. Relative to fasting, telaprevir AUC increased by approximately 117% with a low-fat meal (249 kcal; 3.6 g fat) and 330% with a high-fat meal (928 kcal; 56 g fat). In Phase 3 clinical trials, telaprevir doses were administered within 30 minutes of completing a meal or snack containing approximately 20 grams of fat.

MANAGEMENT: Telaprevir should be administered with food containing approximately 20 grams of fat. Patients should be advised that the fat content of the meal or snack is critical to the absorption of telaprevir. Food taken with telaprevir should be ingested within 30 minutes prior to each dose. Examples of some foods that could be taken with telaprevir include: bagel with cream cheese; half cup of nuts; 3 tablespoons of peanut butter; 1 cup of ice cream; 2 ounces of American or cheddar cheese; 2 ounces of potato chips; or half cup of trail mix.

References (1)
  1. (2011) "Product Information. Incivek (telaprevir)." Vertex Pharmaceuticals
Minor

estropipate food

Applies to: estropipate

Coadministration with grapefruit juice may increase the bioavailability of oral estrogens. The proposed mechanism is inhibition of CYP450 3A4-mediated first-pass metabolism in the gut wall induced by certain compounds present in grapefruits. In a small, randomized, crossover study, the administration of ethinyl estradiol with grapefruit juice (compared to herbal tea) increased peak plasma drug concentration (Cmax) by 37% and area under the concentration-time curve (AUC) by 28%. Based on these findings, grapefruit juice is unlikely to affect the overall safety profile of ethinyl estradiol. However, as with other drug interactions involving grapefruit juice, the pharmacokinetic alterations are subject to a high degree of interpatient variability. Also, the effect on other estrogens has not been studied.

References (2)
  1. Weber A, Jager R, Borner A, et al. (1996) "Can grapefruit juice influence ethinyl estradiol bioavailability?" Contraception, 53, p. 41-7
  2. Schubert W, Eriksson U, Edgar B, Cullberg G, Hedner T (1995) "Flavonoids in grapefruit juice inhibit the in vitro hepatic metabolism of 17B-estradiol." Eur J Drug Metab Pharmacokinet, 20, p. 219-24

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.


Report options

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.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.