Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
DEMULEN 1/35-21 vs ALTAVERA
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Combination oral contraceptive containing ethinyl estradiol (estrogen) and ethynodiol diacetate (progestin). Inhibits gonadotropin secretion (FSH, LH) via negative feedback on hypothalamic-pituitary axis, suppressing ovulation. Additionally, thickens cervical mucus and alters endometrial receptivity.
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,Treatment of moderate acne vulgaris in women at least 15 years old who have achieved menarche and are seeking contraception,Oral contraceptive for women over 35 who smoke (off-label: not recommended due to increased cardiovascular risk)
Prevention of pregnancy,Treatment of moderate acne vulgaris (in females ≥15 years with no contraindications)
One tablet orally once daily for 21 days, followed by 7 days off. Each tablet contains 1 mg ethynodiol diacetate and 35 mcg ethinyl estradiol.
1 tablet (ethinyl estradiol 0.03 mg / levonorgestrel 0.15 mg) orally once daily for 21 days, followed by 7 placebo days.
Ethinyl estradiol: 13±3 hours (terminal); norethindrone: 8±3 hours. Steady-state achieved after ~5 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.
Ethinyl estradiol: primarily metabolized by CYP3A4 hydroxylation and conjugation; undergoes enterohepatic recirculation. Ethynodiol diacetate: rapidly deacetylated to norethindrone, which is metabolized by CYP3A4 and CYP2C9; undergoes reduction, hydroxylation, and conjugation.
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.
Renal (primarily as glucuronide and sulfate conjugates): ~60%; fecal: ~40%
Renal excretion of metabolites and unchanged drug: ~30% (levonorgestrel) and ~20% (ethinyl estradiol) in urine; biliary/fecal elimination: ~40-50% as conjugates and metabolites.
Ethinyl estradiol: 97–98% bound to albumin; norethindrone: 93–97% bound to albumin and SHBG
Levonorgestrel: 98-99% bound to sex hormone-binding globulin (SHBG) and albumin; ethinyl estradiol: 98% bound to albumin.
Ethinyl estradiol: 2.5–4 L/kg; norethindrone: 3.5–5 L/kg. Indicates extensive tissue distribution.
Levonorgestrel: Vd ~1.8 L/kg (suggesting extensive tissue distribution). Ethinyl estradiol: Vd ~2.4 L/kg.
Ethinyl estradiol: ~45% (first-pass metabolism); norethindrone: ~65% (first-pass metabolism). Oral administration only.
Oral bioavailability: levonorgestrel ~100% (nearly complete); ethinyl estradiol ~45-50% (first-pass hepatic metabolism).
No dose adjustment required for renal impairment. However, caution in severe renal impairment due to potential fluid retention.
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 Child-Pugh class B and C (moderate to severe hepatic impairment). Use with caution in mild impairment (Child-Pugh A) with monitoring.
Contraindicated in severe hepatic dysfunction (Child-Pugh class B or C). Use caution in mild to moderate impairment (Child-Pugh A); monitor liver enzymes.
Not indicated for use before menarche. Post-menarche: use same dosing as adults; monitor for bone health and growth.
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 due to lack of efficacy and increased thromboembolic risk.
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 combination oral contraceptive use. 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.
Increased risk of thromboembolic disorders (e.g., stroke, DVT, PE),Increased risk of myocardial infarction, especially in smokers and women with hypertension or hyperlipidemia,Hepatic neoplasia (benign/malignant),Gallbladder disease,Hypertension,Carbohydrate and lipid metabolism changes,Ocular lesions (e.g., retinal thrombosis),Depression,Fluid retention,Irregular bleeding,Possible reduced efficacy with enzyme-inducing drugs (e.g., rifampin, anticonvulsants),Chloasma,Pregnancy (should be ruled out before use)
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.
Thrombophlebitis or thromboembolic disorders (current or history),Cerebrovascular or coronary artery disease (current or history),Known or suspected breast carcinoma,Known or suspected estrogen-dependent neoplasia,Undiagnosed abnormal genital bleeding,Known or suspected pregnancy,Benign or malignant liver tumor (current or history),Severe hepatic impairment or acute liver disease,Hypersensitivity to any component,Age over 35 and smoking (≥15 cigarettes/day),Uncontrolled hypertension (systolic ≥160 mm Hg or diastolic ≥100 mm Hg),Diabetes with vascular involvement,Migraine with focal aura (if age ≥35),Major surgery with prolonged immobilization
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
No significant food interactions. Grapefruit juice may slightly increase estrogen levels but not clinically relevant. Avoid St. John's Wort as it reduces contraceptive efficacy. No dietary restrictions.
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.
First trimester: increased risk of cardiovascular defects (RR ~1.3) and oral clefts (RR ~1.1) with exposure; second and third trimesters: no proven association with major malformations, but may cause masculinization of female genitalia if high doses of progestins (ethynodiol diacetate is a weak progestin, risk low). Postnatal: potential for neonatal jaundice (due to estrogen).
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.
Excreted in breast milk in small amounts (estrogen and progestin levels ~1% of maternal dose; M/P ratio not well defined). May reduce milk quality and quantity; use only if benefits outweigh risks, preferably after weaning.
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.
No dose adjustments; contraindicated during pregnancy due to fetal risks. If used inadvertently, discontinue immediately.
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.
Demulen 1/35-21 (ethinyl estradiol 35 mcg, ethynodiol diacetate 1 mg) is a monophasic combined oral contraceptive. It has lower estrogen dose than many older pills but still carries thromboembolic risk. Advise patients to take at same time daily. Missed pill protocols: if missed >12 hours, take pill ASAP and continue; if missed 2 or more pills, use backup contraception for 7 days. Consider non-contraceptive benefits: improved cycle regularity, reduced dysmenorrhea, decreased acne. Monitor blood pressure and liver function. Contraindications: history of DVT/PE, active liver disease, breast cancer, pregnancy, migraine with aura. Smoking increases thromboembolic risk significantly, especially in women >35.
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 one pill daily at the same time for 21 days, then no pills for 7 days; you will have withdrawal bleeding during the free week.,If you miss a pill by less than 12 hours, take it immediately and continue on schedule. If more than 12 hours, take the missed pill and use backup contraception (condoms) for the next 7 days.,Common side effects include nausea, headache, breast tenderness, breakthrough bleeding, and mood changes; these often improve after the first few months.,Seek medical help for symptoms of blood clots: sudden leg pain/swelling, chest pain, shortness of breath, sudden severe headache or vision changes.,Do not smoke while taking this medication; smoking increases risk of serious cardiovascular side effects, especially if over 35.,This pill does not protect against sexually transmitted infections; use condoms for STI prevention.
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 DEMULEN 1/35-21 vs ALTAVERA, answered by our medical review team.
DEMULEN 1/35-21 is a Oral Contraceptive that works by Combination oral contraceptive containing ethinyl estradiol (estrogen) and ethynodiol diacetate (progestin). Inhibits gonadotropin secretion (FSH, LH) via negative feedback on hypothalamic-pituitary axis, suppressing ovulation. Additionally, thickens cervical mucus and alters endometrial receptivity.. 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 DEMULEN 1/35-21 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 DEMULEN 1/35-21 is: One tablet orally once daily for 21 days, followed by 7 days off. Each tablet contains 1 mg ethynodiol diacetate and 35 mcg ethinyl estradiol.. 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 DEMULEN 1/35-21 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. DEMULEN 1/35-21 is classified as Category C. First trimester: increased risk of cardiovascular defects (RR ~1.3) and oral clefts (RR ~1.1) with exposure; second and third trimesters: no proven association with major malformat. 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.