DROSPIRENONE AND ESTRADIOL
Clinical safety rating: avoid
Inducers of CYP450 enzymes (eg carbamazepine) may decrease estrogen levels Increases risk of thromboembolic disorders and endometrial cancer.
Drospirenone is a progestin with antimineralocorticoid and antiandrogenic activity; estradiol is an estrogen. Drospirenone acts as a progesterone receptor agonist, inhibits ovulation, and increases cervical mucus viscosity. Estradiol replaces endogenous estrogen, suppresses gonadotropin secretion.
| Metabolism | Drospirenone is extensively metabolized by cytochrome P450 3A4 (CYP3A4) to inactive metabolites. Estradiol is primarily metabolized in the liver via CYP1A2 and CYP3A4 to estrone and estriol, and undergoes enterohepatic recirculation. |
| Excretion | Drospirenone: ~40-50% renal, ~50-60% fecal; estradiol: ~60-80% renal (as metabolites), ~20-40% fecal. |
| Half-life | Drospirenone: ~30-40 hours (allows once-daily dosing); estradiol: ~12-15 hours (after oral administration). |
| Protein binding | Drospirenone: ~95-97% bound (mostly to albumin, not SHBG); estradiol: ~98% bound (to SHBG and albumin). |
| Volume of Distribution | Drospirenone: ~2.5-3.5 L/kg (large, extensive tissue distribution); estradiol: ~1-2 L/kg. |
| Bioavailability | Oral drospirenone: ~75-85% (due to first-pass metabolism); oral estradiol: ~5-10% (extensive first-pass; micronized estradiol). |
| Onset of Action | Oral: Onset of contraceptive effect after 7 days of continuous use; onset of hormone replacement effect within 2-3 weeks. |
| Duration of Action | 24 hours; sustained contraceptive effect requires daily dosing; continuous use without breaks for extended cycles. |
| Molecular Weight | 915.12 |
One tablet (drospirenone 3 mg / estradiol 0.5 mg) orally once daily for hormone therapy.
| Dosage form | TABLET |
| Renal impairment | Contraindicated in severe renal impairment (eGFR < 30 mL/min/1.73 m²) due to risk of hyperkalemia. No dose adjustment for mild to moderate impairment (eGFR 30-89 mL/min/1.73 m²); use with caution and monitor potassium. |
| Liver impairment | Contraindicated in Child-Pugh C (severe hepatic impairment). Not recommended in Child-Pugh B (moderate impairment) as safety not established. Use with caution in Child-Pugh A (mild impairment) with monitoring. |
| Pediatric use | Not indicated for use in pediatric patients. Safety and efficacy not established. |
| Geriatric use | Use with caution in patients over 65 years due to limited data. No specific dose adjustment recommended, but consider increased risk of thromboembolic events and hyperkalemia. |
| 1st trimester | Use contraindicated; risk of fetal harm including cardiovascular and neurological defects, and possible carcinogenic effects. |
| 2nd trimester | Use contraindicated; potential for adverse effects on fetal development and risk of maternal thromboembolic events. |
| 3rd trimester | Use contraindicated; may cause premature closure of fetal ductus arteriosus, neonatal hepatic dysfunction, and other fetal abnormalities. |
Clinical note
Inducers of CYP450 enzymes (eg carbamazepine) may decrease estrogen levels Increases risk of thromboembolic disorders and endometrial cancer.
| FDA category | Positive |
| Placental transfer | Crosses placenta; detected in fetal circulation. Risk to fetus outweighs any potential benefit. |
| Breastfeeding |
■ FDA Black Box Warning
Cigarette smoking increases the risk of serious cardiovascular events from combination oral contraceptive use. This risk increases with age (especially in women over 35 years) and with the number of cigarettes smoked. Women who use combination hormonal contraceptives should be strongly advised not to smoke.
| Common Effects | osteoporosis prevention |
| Serious Effects |
Known or suspected pregnancyBreastfeedingHypersensitivity to drospirenone or estradiolHistory of or current thromboembolic disorders (e.g., deep vein thrombosis, pulmonary embolism)History of or current cerebrovascular disease (e.g., stroke)Known or suspected estrogen-dependent neoplasia (e.g., breast cancer, endometrial cancer)Undiagnosed abnormal genital bleedingLiver disease (including hepatic adenomas or carcinoma)Renal insufficiency (creatinine clearance < 30 mL/min)Adrenal insufficiencyUse of hepatitis C drug combinations containing ombitasvir/paritaprevir/ritonavir with or without dasabuvirPorphyria
| Precautions | Thrombotic disorders and other vascular problems, Liver disease, Hypertension, Gallbladder disease, Carbohydrate and lipid metabolic effects, Headache/migraine, Bleeding irregularities, Depression, Carcinoma of the breast and reproductive organs, Hereditary angioedema, Chloasma, Hyperkalemia (due to drospirenone's antimineralocorticoid effect, especially in patients with renal impairment, hepatic impairment, or adrenal insufficiency) |
Loading safety data…
| Excreted in breast milk; may reduce milk production and alter milk composition. Use not recommended in breastfeeding women. Consider alternative contraception methods. |
| Lactation Rating | Avoid |
| Teratogenic Risk | Pregnancy category X. Contraindicated in pregnancy. First trimester: Increased risk of cardiovascular and limb defects. Second and third trimesters: Risk of fetal urogenital abnormalities, feminization of male fetuses. Associated with hypospadias and congenital heart defects. |
| Fetal Monitoring | Not applicable in pregnancy (contraindicated). In non-pregnant women: measure blood pressure 3 months after initiation, monitor serum potassium in predisposed conditions (renal impairment, adrenal insufficiency, hepatic dysfunction). |
| Fertility Effects | Reversible inhibition of ovulation. Can impair fertility during use. Return to normal fertility upon discontinuation. |
| Food/Dietary | No food interactions; however, avoid grapefruit juice if also taking CYP3A4 substrates (not specific to this combination). Maintain adequate hydration but no potassium-rich diet restrictions unless renal impairment. |
| Clinical Pearls | Monitor serum potassium during first month of therapy due to drospirenone's antimineralocorticoid effects; contraindicated in renal insufficiency (CrCl <30 mL/min) and adrenal insufficiency. Assess thrombotic risk factors before initiation. Use in women with BMI >30 kg/m² increases risk of VTE. |
| Patient Advice | Take one tablet daily at the same time; missed dose can cause breakthrough bleeding. · Report symptoms of blood clots (leg swelling/pain, sudden chest pain, difficulty breathing). · Do not use with potassium supplements, potassium-sparing diuretics, or ACE inhibitors without monitoring. · If you have kidney or adrenal disease, this medication is not safe for you. · Smoking increases risk of serious cardiovascular side effects; avoid smoking. · During first few cycles, irregular bleeding may occur; contact your doctor if prolonged. |