Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
NATAZIA vs ALTAVERA
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Estetrol is a selective estrogen receptor modulator (SERM) with mixed agonist/antagonist activity; drospirenone is a spironolactone analog with antimineralocorticoid and antiandrogenic activity. Combined oral contraceptive inhibits ovulation and alters cervical mucus.
Combination of ethinyl estradiol and desogestrel: ethinyl estradiol suppresses gonadotropin release, inhibiting ovulation; desogestrel (progestin) causes cervical mucus thickening and endometrial atrophy, preventing implantation.
Prevention of pregnancy
Prevention of pregnancy,Treatment of moderate acne vulgaris (in females ≥15 years with no contraindications)
Drospirenone 3 mg / ethinyl estradiol 0.03 mg orally once daily for 21 days followed by 7 days of placebo.
1 tablet (ethinyl estradiol 0.03 mg / levonorgestrel 0.15 mg) orally once daily for 21 days, followed by 7 placebo days.
Terminal half-life approximately 30 hours for drospirenone and 24 hours for ethinyl estradiol; steady-state achieved within 8–10 days.
Levonorgestrel: terminal elimination half-life 25±10 hours; ethinyl estradiol: 13±7 hours. Clinical context: steady-state concentrations achieved within 5-7 days; contraceptive efficacy requires consistent daily dosing.
Estetrol is metabolized primarily via glucuronidation (UGT1A1, UGT1A3, UGT1A9) and sulfation (SULT1E1). Drospirenone is metabolized via CYP3A4 and to a lesser extent by CYP1A1 and CYP2C9.
Ethinyl estradiol: primarily metabolized by CYP3A4; undergoes sulfation and glucuronidation. Desogestrel: rapidly converted to active metabolite etonogestrel via CYP2C9 and CYP2C19; further metabolism by CYP3A4.
Fecal excretion is the primary route (approximately 68%), with renal excretion accounting for about 27% (mostly as metabolites).
Renal excretion of metabolites and unchanged drug: ~30% (levonorgestrel) and ~20% (ethinyl estradiol) in urine; biliary/fecal elimination: ~40-50% as conjugates and metabolites.
Drospirenone: 95–97% bound to albumin (not to SHBG or CBG). Ethinyl estradiol: 98% bound to albumin.
Levonorgestrel: 98-99% bound to sex hormone-binding globulin (SHBG) and albumin; ethinyl estradiol: 98% bound to albumin.
Drospirenone: Vd approximately 0.7-1.0 L/kg. Ethinyl estradiol: Vd approximately 1.2-1.5 L/kg.
Levonorgestrel: Vd ~1.8 L/kg (suggesting extensive tissue distribution). Ethinyl estradiol: Vd ~2.4 L/kg.
Drospirenone: absolute oral bioavailability approximately 76–85%. Ethinyl estradiol: oral bioavailability approximately 40–50% (first-pass metabolism).
Oral bioavailability: levonorgestrel ~100% (nearly complete); ethinyl estradiol ~45-50% (first-pass hepatic metabolism).
Contraindicated in patients with renal impairment (Cr Cl < 30 m L/min) due to risk of hyperkalemia. No dose adjustment required for mild to moderate impairment, but monitor serum potassium.
No dose adjustment required for mild to moderate renal impairment. Contraindicated in severe renal disease or acute renal failure due to potential fluid retention.
Contraindicated in acute liver disease or decompensated cirrhosis (Child-Pugh C). No dose adjustment for mild impairment (Child-Pugh A); use with caution in moderate impairment (Child-Pugh B) and monitor liver function.
Contraindicated in severe hepatic dysfunction (Child-Pugh class B or C). Use caution in mild to moderate impairment (Child-Pugh A); monitor liver enzymes.
Same as adult dosing for postmenarchal adolescents, but not indicated before menarche. Weight-based adjustments not established.
Not indicated for use before menarche. For postmenarchal adolescents, same dosing as adults (1 tablet daily, 21/7 regimen) after evaluation of risks.
Not indicated for use in postmenopausal women; no specific dosing studies. In elderly with normal renal and hepatic function, standard dosing may be used, but consider increased risk of thromboembolism and cardiovascular events.
Not indicated for postmenopausal women. No specific geriatric dosing; consider increased risk of thromboembolism, cardiovascular disease, and metabolic effects in older women of reproductive age.
Cigarette smoking increases risk of serious cardiovascular events from combined oral contraceptives. Risk increases with age and heavy smoking (≥15 cigarettes/day). Women over 35 who smoke should not use this product.
Cigarette smoking increases risk of serious cardiovascular events from combined oral contraceptives. Risk increases with age (especially >35 years) and with number of cigarettes smoked. Women who use combined hormonal contraceptives should be strongly advised not to smoke.
Thrombotic disorders (venous and arterial),Cerebrovascular disease,Myocardial infarction,Breast cancer risk,Liver disease,Hypertension,Hyperkalemia (drospirenone component),Carbohydrate and lipid metabolism effects,Headache/migraine,Uterine bleeding irregularities,Depression
Thrombotic disorders: risk of venous thromboembolism (VTE), stroke, myocardial infarction; discontinue if thrombotic event occurs.,Hepatic disease: discontinue if jaundice or liver function abnormalities develop.,Hypertension: monitor blood pressure; discontinue if uncontrolled.,Carbohydrate metabolism: may affect glucose tolerance; monitor diabetic patients.,Depression: discontinue if significant depression occurs.,Gallbladder disease: increased risk of cholelithiasis.
Current or history of venous or arterial thrombosis,Cerebrovascular disease,Myocardial infarction or coronary artery disease,Breast cancer or other estrogen- or progestin-sensitive cancer,Liver tumors (benign or malignant) or active liver disease,Undiagnosed abnormal uterine bleeding,Known or suspected pregnancy,Renal impairment (creatinine clearance <30 m L/min),Adrenal insufficiency,Hypersensitivity to any component,Smoking and age ≥35 years
Thrombophlebitis or thromboembolic disorders (current or history),Cerebrovascular or coronary artery disease (current or history),Known or suspected breast carcinoma,Estrogen-dependent neoplasia (known or suspected),Undiagnosed abnormal genital bleeding,Cholestatic jaundice of pregnancy or jaundice with prior pill use,Hepatic adenoma or carcinoma (known or suspected),Pregnancy (known or suspected),Hypersensitivity to any component
Grapefruit and grapefruit juice may increase estrogen exposure and should be avoided. No other specific food interactions reported. Maintain a consistent diet to avoid variable contraceptive efficacy.
No significant food interactions. Alcohol does not affect efficacy but may increase risk of adverse effects such as nausea. Grapefruit juice has no known interaction. Avoid excessive alcohol consumption due to potential hepatotoxicity.
Pregnancy Category X. First trimester: high risk of severe fetal malformations including CNS, cardiovascular, and craniofacial defects (e.g., neural tube defects, cardiac septal defects). Second and third trimesters: increased risk of fetal growth restriction, oligohydramnios, and neonatal renal impairment due to direct fetal toxicity.
ALTAVERA contains ethinyl estradiol and levonorgestrel. First trimester: Inadvertent exposure during organogenesis is associated with a very low absolute risk of cardiovascular defects (relative risk 1.2-1.4) and no consistent increase in other major malformations. Second and third trimesters: No known teratogenic effects, but theoretical risks from estrogenic effects (e.g., feminization of male fetus). Postnatal: No increased risk of long-term developmental effects from pregnancy exposure.
Contraindicated during breastfeeding. No human data on M/P ratio; animal studies indicate significant excretion into milk with potential for severe adverse effects including growth retardation and renal toxicity in nursing infants.
Combined oral contraceptives may reduce milk production and quality, especially in early lactation. Ethinyl estradiol transfers into breast milk at low levels (M/P ratio approximately 0.1-0.2), excluding clinical effects in term infants. Levonorgestrel transfer is minimal (M/P ratio ~0.2-0.4). Use is generally avoided in breastfeeding women, especially during the first 6 weeks postpartum. Progestin-only methods are preferred.
Not applicable; contraindicated in pregnancy. If inadvertent exposure occurs, discontinue immediately; no dose adjustment is recommended as the drug should be avoided entirely.
Contraindicated in pregnancy. No dose adjustment recommended because use is discontinued upon confirmed or suspected pregnancy. Pharmacokinetic changes in pregnancy (e.g., increased hepatic clearance, altered binding proteins) are not relevant for this indication.
NATAZIA (estradiol valerate/dienogest) is a four-phasic oral contraceptive. It is contraindicated in women with hepatic impairment, active liver disease, or a history of liver tumors. Due to the progestin dienogest, it may have antiandrogenic effects, beneficial for acne or hirsutism. Missed pills require specific instructions due to the dynamic dosing schedule; use a backup method if pills are missed during the first week.
ALTAVERA is a combined oral contraceptive (COC) containing ethinylestradiol and levonorgestrel. It inhibits ovulation via suppression of gonadotropins. Counsel patients to take at the same time daily to maintain efficacy. Missed pill management: if missed within 12 hours, take immediately; if >12 hours, take last missed pill and use backup contraception for 7 days. Be aware of increased VTE risk, especially in smokers over 35. May reduce effectiveness of lamotrigine; monitor seizure control. Initiate on the first day of menses or first Sunday after onset.
Take the pills in the exact order on the blister pack, starting with the first pill on the first day of your menstrual period.,Swallow the tablet whole with some liquid, with or without food.,If you vomit or have severe diarrhea within 3-4 hours of taking a pill, it may not be fully absorbed; consider it as a missed pill.,You may not have a withdrawal bleed every month; if you miss two withdrawal bleeds in a row, check for pregnancy.,NATAZIA does not protect against HIV or other sexually transmitted infections.
Take one tablet daily at the same time each day, with or without food.,If you miss a pill by less than 12 hours, take it as soon as you remember. If more than 12 hours, take the missed pill and use a backup method (e.g., condoms) for the next 7 days.,Smoking increases your risk of serious cardiovascular side effects, especially if you are over 35 years old. Do not smoke while taking this medication.,Seek immediate medical attention if you experience sudden severe headache, chest pain, leg pain/swelling, or vision changes (symptoms of blood clots).,This medication does not protect against HIV or other sexually transmitted infections.,If you are taking lamotrigine or other anticonvulsants, tell your doctor; your seizure medication may be less effective.,Store at room temperature away from moisture and heat.
No interactions on record
No interactions on record
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about NATAZIA vs ALTAVERA, answered by our medical review team.
NATAZIA is a Oral Contraceptive that works by Estetrol is a selective estrogen receptor modulator (SERM) with mixed agonist/antagonist activity; drospirenone is a spironolactone analog with antimineralocorticoid and antiandrogenic activity. Combined oral contraceptive inhibits ovulation and alters cervical mucus.. ALTAVERA is a Combined Oral Contraceptive that works by Combination of ethinyl estradiol and desogestrel: ethinyl estradiol suppresses gonadotropin release, inhibiting ovulation; desogestrel (progestin) causes cervical mucus thickening and endometrial atrophy, preventing implantation.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between NATAZIA and ALTAVERA depend on the specific clinical indication. These are agents from distinct pharmacological classes and are not directly interchangeable by dose. A physician or clinical pharmacist should guide any therapeutic switching decisions.
The standard adult dose of NATAZIA is: Drospirenone 3 mg / ethinyl estradiol 0.03 mg orally once daily for 21 days followed by 7 days of placebo.. The standard adult dose of ALTAVERA is: 1 tablet (ethinyl estradiol 0.03 mg / levonorgestrel 0.15 mg) orally once daily for 21 days, followed by 7 placebo days.. Dosing should always be individualized based on indication, renal and hepatic function, age, and other patient factors.
No direct drug-drug interaction has been formally documented between NATAZIA and ALTAVERA in current clinical databases. However, individual patient risk factors including other medications, organ function, and comorbidities should always be evaluated by a qualified healthcare provider.
The maternal-fetal safety profiles differ. NATAZIA is classified as Category C. Pregnancy Category X. First trimester: high risk of severe fetal malformations including CNS, cardiovascular, and craniofacial defects (e.g., neural tube defects, cardiac septal de. ALTAVERA is classified as Category C. ALTAVERA contains ethinyl estradiol and levonorgestrel. First trimester: Inadvertent exposure during organogenesis is associated with a very low absolute risk of cardiovascular def. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.