ESTRADIOL VALERATE AND DIENOGEST
Clinical safety rating: avoid
Inducers of CYP450 enzymes (eg carbamazepine) may decrease estrogen levels Increases risk of thromboembolic disorders and endometrial cancer.
Estradiol valerate is a prodrug of estradiol, an estrogen that binds to estrogen receptors (ERα and ERβ) to regulate gene transcription, promoting endometrial growth and suppressing gonadotropins. Dienogest is a progestin with partial antiandrogenic activity, binding to progesterone receptors to inhibit endometrial proliferation and ovulation, and reducing androgen synthesis.
| Metabolism | Estradiol valerate is hydrolyzed to estradiol, which is metabolized via CYP3A4 and CYP1A2 to estrone, estriol, and catechol estrogens, undergoing conjugation and enterohepatic recirculation. Dienogest is metabolized primarily by CYP3A4 to inactive hydroxylated metabolites, with negligible antiandrogenic metabolite activity. |
| Excretion | Estradiol valerate: Renal (primarily as glucuronide and sulfate conjugates) ~40%, Fecal ~60%. Dienogest: Renal ~60% (mostly unchanged), Fecal ~30%. |
| Half-life | Estradiol valerate: Terminal half-life of estradiol is 13-15 hours; valerate ester is rapidly hydrolyzed, so systemic estradiol half-life applies. Dienogest: Terminal half-life ~8-10 hours, increasing to ~12-14 hours with multiple dosing due to competitive inhibition of CYP3A4. |
| Protein binding | Estradiol: ~98% bound to sex hormone-binding globulin (SHBG) and albumin. Dienogest: ~90% bound primarily to albumin, not SHBG. |
| Volume of Distribution | Estradiol: Vd ~1.2 L/kg (adults), indicating extensive tissue distribution. Dienogest: Vd ~40-50 L (approx. 0.6 L/kg), moderate distribution. |
| Bioavailability | Oral: Estradiol valerate has low oral bioavailability (~5%) due to extensive first-pass metabolism; the valerate ester is cleaved to active estradiol. Dienogest: High oral bioavailability (~90-95%) due to no first-pass effect and high intestinal absorption. |
| Onset of Action | Oral: Estradiol valerate undergoes first-pass metabolism; clinical effects (e.g., hemostatic or endometrial effects) begin within 1-2 weeks. Dienogest: No immediate effect; clinical efficacy in conditions like endometriosis requires continuous dosing over weeks. |
| Duration of Action | Oral: 24-hour dosing interval required for both components; once-daily administration maintains stable serum levels. Clinical duration for cycle control and contraception is the duration of intake (21 or 28 days). |
One tablet (2 mg estradiol valerate and 3 mg dienogest) once daily orally, without interruption, following the first day of menstrual cycle.
| Dosage form | TABLET |
| Renal impairment | No dose adjustment required for mild to moderate renal impairment. Contraindicated in severe renal impairment or acute renal failure. |
| Liver impairment | Contraindicated in severe hepatic disease (Child-Pugh class C). Use with caution in mild to moderate hepatic impairment; no specific dose adjustment defined. |
| Pediatric use | Not indicated for use in postmenarchal adolescents. Safety and efficacy not established. |
| Geriatric use | Not indicated for use in postmenopausal women. No specific geriatric dosing recommendations; consider increased risk of thromboembolism and malignancy. |
| 1st trimester | Consult provider |
| 2nd trimester | Consult provider |
| 3rd trimester | Consult provider |
Clinical note
Inducers of CYP450 enzymes (eg carbamazepine) may decrease estrogen levels Increases risk of thromboembolic disorders and endometrial cancer.
| FDA category | Positive |
| Breastfeeding | Excreted in human milk; estradiol valerate and dienogest can reduce milk production and change milk composition. M/P ratio not established. Avoid use during breastfeeding due to potential adverse effects on infant hormonal balance. Consider alternative contraception. |
| Teratogenic Risk |
■ FDA Black Box Warning
Cigarette smoking increases risk of serious cardiovascular events from combined hormonal contraceptives. Risk increases with age (especially >35 years) and with heavy smoking (≥15 cigarettes/day). Women should not use this drug if they smoke and are over 35 years of age.
| Common Effects | osteoporosis prevention |
| Serious Effects |
["Breast cancer or other estrogen/progestin-sensitive neoplasia (current or history)","Hepatic tumors (benign or malignant) or active liver disease","History of deep vein thrombosis or pulmonary embolism","Active thromboembolic disorders (e.g., stroke, MI, angina)","Known thrombophilic conditions (e.g., Factor V Leiden, antiphospholipid syndrome)","Undiagnosed abnormal uterine bleeding","Pregnancy or suspected pregnancy","Hypersensitivity to any component","Migraine with focal aura at any age","Diabetes with vascular involvement","Uncontrolled hypertension (≥160/100 mmHg)","Major surgery with prolonged immobilization","Smoking and age >35 years"]
| Precautions | ["Thrombotic disorders: venous thromboembolism, arterial thromboembolism, stroke, myocardial infarction","Hepatic disease: discontinue if jaundice or acute/chronic liver dysfunction occurs","Hypertension: monitor blood pressure; discontinue if uncontrolled","Gallbladder disease: increased risk of gallstones","Carbohydrate/lipid effects: monitor in diabetic or hyperlipidemic patients","Headache: evaluate for migraine or increased frequency/severity","Uterine bleeding: rule out malignancy if irregular bleeding persists","Depression: discontinue if severe or recurrent","Angioedema: increased risk in women with hereditary angioedema"] |
Loading safety data…
| Pregnancy category X. First trimester: association with hypospadias, cardiovascular malformations, and orofacial clefts based on limited data. Second and third trimesters: risk of hormonal adverse effects on fetal genital development (female pseudohermaphroditism with androgens; estrogens may cause vaginal adenosis or cervical changes). Estrogen-containing contraceptives are contraindicated in pregnancy due to potential fetal harm from dienogest as a progestin with antiandrogenic activity. Discontinue immediately if pregnancy occurs. |
| Fetal Monitoring | Pregnancy test before initiating therapy to exclude pregnancy; monitor liver function, blood pressure, clotting parameters (due to estrogen-related thrombotic risk); clinical monitoring for signs of thromboembolism. If pregnancy occurs, discontinue drug and perform fetal ultrasound for structural anomalies. |
| Fertility Effects | Suppresses ovulation via inhibition of gonadotropins (FSH, LH) leading to decreased follicular development. After discontinuation, fertility returns to baseline; no long-term detrimental effects on fertility have been established. May cause menstrual irregularities initially. |