Drug Interactions between Adgyn Estro and elvitegravir
This report displays the potential drug interactions for the following 2 drugs:
- Adgyn Estro (estradiol)
- elvitegravir
Interactions between your drugs
estradiol elvitegravir
Applies to: Adgyn Estro (estradiol) and elvitegravir
ADDITIONAL CONTRACEPTION RECOMMENDED: Coadministration with cobicistat and elvitegravir may alter the plasma concentrations of contraceptive hormones. The exact mechanism of interaction has not been described. In 13 study subjects, administration of ethinyl estradiol 0.025 mg and norgestimate 0.18 to 0.25 mg once daily in combination with elvitegravir 150 mg plus cobicistat 150 mg once daily decreased the mean ethinyl estradiol peak plasma concentration (Cmax), systemic exposure (AUC) and trough plasma concentration (Cmin) by 6%, 25% and 44%, respectively. In contrast, norgestimate Cmax, AUC and Cmin increased by 2.08-, 2.26- and 2.67-fold, respectively. Clinical effects of increased progestogen levels are not fully known, but may include increased risk of insulin resistance, dyslipidemia, acne, and venous thrombosis.
MANAGEMENT: The potential risks and benefits of using norgestimate-containing contraceptives in combination with cobicistat and elvitegravir should be considered, particularly in women who have risk factors for insulin resistance, dyslipidemia, acne, and venous thrombosis. Coadministration of cobicistat and elvitegravir with other hormonal contraceptives (e.g., contraceptive patch, contraceptive vaginal ring, or injectable contraceptives), oral contraceptives containing progestogens other than norgestimate, or less than 25 mcg of ethinyl estradiol has not been studied and is not recommended. Some authorities recommend that hormonal contraceptives containing at least 30 mcg of ethinyl estradiol with norgestimate should be used in combination with the multi-ingredient antiretroviral formulations containing elvitegravir/cobicistat/emtricitabine/tenofovir disoproxil fumarate or elvitegravir/cobicistat/emtricitabine/tenofovir alafenamide. However, the long term effects of increased progesterone exposure are not known. Alternative, nonhormonal methods of contraception may be considered.
References
- Cerner Multum, Inc. "UK Summary of Product Characteristics."
- Cerner Multum, Inc. "Australian Product Information."
- (2012) "Product Information. Stribild (cobicistat/elvitegravir/emtricitabine/tenofov)." Gilead Sciences
Drug and food interactions
elvitegravir food
Applies to: elvitegravir
ADJUST DOSING INTERVAL: Food enhances the oral bioavailabilities of both elvitegravir and tenofovir. When a single dose of cobicistat/elvitegravir/emtricitabine/tenofovir (trade name Stribild) was given with a light meal (approximately 373 kcal; 20% fat), mean elvitegravir and tenofovir systemic exposures (AUCs) increased by 34% and 24%, respectively, relative to fasting conditions. When administered with a high-fat meal (approximately 800 kcal; 50% fat), the mean AUC of elvitegravir and tenofovir increased by 87% and 23%, respectively, relative to fasting conditions. The alterations in mean AUCs of cobicistat and emtricitabine were not clinically significant with either the light or high-fat meal.
MANAGEMENT: Cobicistat/elvitegravir/emtricitabine/tenofovir as a fixed-dose preparation should be administered once daily with food. Elvitegravir as a single-ingredient preparation should also be administered once daily with food.
References
- (2012) "Product Information. Stribild (cobicistat/elvitegravir/emtricitabine/tenofov)." Gilead Sciences
- (2014) "Product Information. Vitekta (elvitegravir)." Gilead Sciences
estradiol food
Applies to: Adgyn Estro (estradiol)
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
- Weber A, Jager R, Borner A, et al. (1996) "Can grapefruit juice influence ethinyl estradiol bioavailability?" Contraception, 53, p. 41-7
- 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.
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
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.
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