Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
LO MINASTRIN FE vs DEMULEN 1/50-28
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 norethindrone (progestin). Inhibits ovulation by suppressing gonadotropin release; increases viscosity of cervical mucus, inhibiting sperm penetration; alters endometrial lining, reducing implantation likelihood.
Combination oral contraceptive: Ethinyl estradiol and ethynodiol diacetate suppress gonadotropin secretion (LH, FSH) via negative feedback, inhibiting ovulation. Ethynodiol diacetate also increases cervical mucus viscosity and induces endometrial changes.
Prevention of pregnancy,Treatment of moderate acne vulgaris in females ≥15 years of age who have no known contraindications, desire oral contraception, and have achieved menarche
FDA: Prevention of pregnancy,Off-label: Treatment of acne vulgaris, dysmenorrhea, endometriosis-related pain, menstrual irregularity
1 tablet (1 mg norethindrone acetate/20 mcg ethinyl estradiol/ferrous fumarate 75 mg) orally once daily for 28 consecutive days.
One tablet orally once daily for 28 consecutive days per cycle.
Norethindrone: 8-11 hours; ethinyl estradiol: 12-16 hours. Steady-state achieved after 5-7 days of dosing.
Ethinylestradiol: terminal elimination half-life ~13-27 hours (mean ~17 hours); ethynodiol diacetate (as norethindrone): terminal elimination half-life ~8-11 hours; clinical context: achieved steady-state within 5-10 days; accumulation not significant due to dose interval.
Hepatic via CYP3A4 (ethinyl estradiol) and primarily reduction and conjugation (norethindrone); undergoes first-pass metabolism.
Ethinyl estradiol: CYP3A4; undergoes first-pass metabolism with sulfation and glucuronidation. Ethynodiol diacetate: Deacetylated to norethynodrel, then extensively metabolized via reduction and conjugation.
Renal: 40-50% as conjugated metabolites; fecal: 20-30% via biliary excretion; unchanged drug <1%.
Ethinylestradiol and ethynodiol diacetate are extensively metabolized; urinary excretion accounts for ~40% of ethinylestradiol metabolites and ~50-60% of ethynodiol diacetate metabolites; fecal excretion accounts for ~30% of ethinylestradiol metabolites and ~35% of ethynodiol diacetate metabolites; biliary excretion contributes to enterohepatic circulation.
Norethindrone: 97% bound (primarily to albumin and SHBG); ethinyl estradiol: 98% bound (primarily to albumin).
Ethinylestradiol: >97% bound, primarily to albumin, with ~2% bound to sex hormone-binding globulin (SHBG); ethynodiol diacetate (as norethindrone): ~95% bound, primarily to albumin and SHBG.
Norethindrone: 4 L/kg; ethinyl estradiol: 2-4 L/kg; reflects extensive tissue distribution and binding to sex hormone receptors.
Ethinylestradiol: Vd ~2-4 L/kg; distributes extensively into body tissues; ethynodiol diacetate (as norethindrone): Vd ~4 L/kg; indicates wide distribution including reproductive tissues.
Oral: norethindrone ~64%, ethinyl estradiol ~40-48% due to first-pass metabolism.
Oral: ethinylestradiol bioavailability ~40-60% due to first-pass metabolism; ethynodiol diacetate bioavailability ~60-80% after oral administration.
No dose adjustment required for mild to moderate renal impairment (GFR ≥30 m L/min). Contraindicated in severe renal impairment (GFR <30 m L/min) or acute renal failure due to potential for hyperkalemia from ferrous fumarate.
No dosage adjustment required for renal impairment. Use is not recommended in patients with severe renal impairment due to potential adverse effects.
Contraindicated in Child-Pugh class B or C (moderate to severe hepatic impairment). For Child-Pugh class A, use caution; consider lower dose estrogen combination if necessary.
Contraindicated in patients with Child-Pugh C cirrhosis. For Child-Pugh A or B, use is generally not recommended; if used, monitor closely for adverse effects.
Not indicated for use prepubertal. Approved for females of reproductive potential; safety and efficacy in children <12 years not established. Follow adult dosing postmenarche.
Not indicated for use before menarche. For postmenarchal adolescents, same dosing as adults: one tablet orally once daily for 28 days per cycle.
Not indicated for use in postmenopausal women. In women >35 years who smoke, use is contraindicated due to increased cardiovascular risk.
Not indicated for use in postmenopausal women. No specific dose adjustment recommended for elderly, but consider increased risk of thromboembolic disorders.
Cigarette smoking increases risk of serious cardiovascular events from combination oral contraceptive use. Risk increases with age (>35 years) and with heavy smoking (≥15 cigarettes/day). Women >35 years who smoke should not use combination oral contraceptives.
Cigarette smoking increases risk of serious cardiovascular events (e.g., myocardial infarction, stroke, thromboembolism). Risk increases with age and heavy smoking (≥15 cigarettes/day). Women over 35 who smoke should not use this product.
Thrombotic disorders (thrombophlebitis, pulmonary embolism, cerebrovascular accidents, myocardial infarction),Hepatic disease (benign/malignant tumors),Hypertension,Gallbladder disease,Carbohydrate/lipid metabolism effects,Ocular changes (retinal thrombosis),Headache/migraine,Uterine bleeding irregularities,Depression,Cervical cancer screening,Pregnancy test prior to initiation,Lactation (possible decreased milk production)
Thromboembolic disorders (DVT, PE, stroke, MI),Hepatic neoplasia (benign/malignant liver tumors),Increased risk of gallbladder disease,Hypertension,Carbohydrate/lipid metabolic effects,Ocular disturbances (retinal thrombosis, optic neuritis),Depression,Fetal harm if used during pregnancy
Thrombophlebitis or thromboembolic disorders (current or history),Cerebrovascular or coronary artery disease,Known or suspected breast carcinoma,Carcinoma of endometrium or other estrogen-dependent neoplasia,Undiagnosed abnormal genital bleeding,Cholestatic jaundice of pregnancy or jaundice with prior pill use,Hepatic adenoma or carcinoma,Known or suspected pregnancy,Hypersensitivity to any component,Heavy smoking (>15 cigarettes/day) in women >35 years
Thrombophlebitis or thromboembolic disorders (current or history),Cerebrovascular or coronary artery disease,Known or suspected breast cancer,Endometrial carcinoma or other estrogen-dependent neoplasia,Undiagnosed abnormal genital bleeding,Cholestatic jaundice of pregnancy or jaundice with prior pill use,Hepatic adenoma or carcinoma,Known or suspected pregnancy,Hypersensitivity to any component
No significant food interactions. Grapefruit juice may increase ethinyl estradiol levels, but clinical significance is minimal. Avoid alcohol if liver function is compromised. Iron absorption from ferrous fumarate is enhanced by vitamin C, but not clinically important.
No significant food interactions. Grapefruit juice may increase estrogen levels, but clinical significance is unclear. Maintain consistent intake of vitamin C-rich foods as they may increase estrogen absorption. Avoid St. John's wort, which reduces contraceptive efficacy.
Pregnancy category X. Contraindicated in pregnancy due to risk of fetal harm. First trimester use associated with cardiovascular defects, neural tube defects; second/third trimester use associated with fetal genital changes, hepatic adenoma.
Contraindicated in pregnancy. First trimester: increased risk of neural tube defects, congenital heart defects, and limb reduction defects from progestins. Second and third trimesters: association with masculinization of female fetus, adrenal suppression, and possible long-term metabolic effects. Estrogen component may increase risk of VACTERL anomalies.
Excreted in breast milk in small amounts (M/P ratio ~0.5). No adverse effects reported in infants, but may reduce milk production. Use with caution.
Contraindicated during breastfeeding. Estrogens reduce milk production and quality. M/P ratio not established; ethinyl estradiol and norgestrel are excreted in breast milk in small amounts, potentially causing adverse effects in the infant.
No dose adjustment indicated as drug is contraindicated in pregnancy.
No adjustments; absolute contraindication in pregnancy. Drug should be discontinued immediately upon pregnancy diagnosis. No established safe dose in pregnancy.
LO MINASTRIN FE is a low-dose combination oral contraceptive (1 mg norethindrone acetate / 20 mcg ethinyl estradiol) with ferrous fumarate tablets. It is indicated for contraception and may improve menstrual regularity. The iron component is not bioavailable during active hormone intake; iron tablets are placebo-day supplements. Monitor for thromboembolic risks, especially in smokers over 35. Breakthrough bleeding is common in the first few cycles. Do not use in hepatic disease or known pregnancy.
Demulen 1/50-28 is a monophasic combined oral contraceptive containing ethinyl estradiol 50 mcg and ethynodiol diacetate 1 mg. Due to the 50 mcg estrogen dose, it carries an increased risk of venous thromboembolism compared to lower-dose pills; avoid in patients with migraine with aura, hypertension >160/100 mm Hg, or age >35 who smoke. The 28-day pack includes 21 active pills and 7 placebo pills; breakthrough bleeding is more common with higher estrogen. Caution with hepatic enzyme inducers like rifampin or anticonvulsants may reduce efficacy.
Take one tablet daily at the same time; the last 7 tablets contain iron instead of hormones.,Missed dose: if missed within 12 hours, take it as soon as remembered; if more than 12 hours, skip the missed dose and continue schedule; use back-up contraception for 7 days.,Smoking increases risk of serious cardiovascular side effects; avoid smoking, especially if over 35 years old.,Inform your healthcare provider of any new onset headaches, chest pain, leg pain/swelling, or visual disturbances.,Breakthrough bleeding is common initially; if persistent, consult your doctor.,Use additional non-hormonal contraception during first 7 days of starting the pill.,Store at room temperature; keep out of reach of children; iron tablets may be harmful to children if ingested.
Take one pill daily at the same time, preferably with food to reduce nausea.,The first 7 days of the first cycle require a backup contraceptive method if not starting on day 1 of menses.,Missed pill: if one active pill is missed, take it as soon as remembered and continue; if two or more active pills are missed, take the last missed pill, skip the others, use backup for 7 days, and consider emergency contraception.,Smoking increases risk of serious cardiovascular side effects; avoid smoking, especially if over 35.,Report symptoms of blood clots: sudden leg pain/swelling, chest pain, shortness of breath, or severe headache.,The 7 placebo pills are for withdrawal bleeding; start next pack on time regardless of bleeding.
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 LO MINASTRIN FE vs DEMULEN 1/50-28, answered by our medical review team.
LO MINASTRIN FE is a Combination Oral Contraceptive that works by Combination oral contraceptive containing ethinyl estradiol (estrogen) and norethindrone (progestin). Inhibits ovulation by suppressing gonadotropin release; increases viscosity of cervical mucus, inhibiting sperm penetration; alters endometrial lining, reducing implantation likelihood.. DEMULEN 1/50-28 is a Combination Oral Contraceptive that works by Combination oral contraceptive: Ethinyl estradiol and ethynodiol diacetate suppress gonadotropin secretion (LH, FSH) via negative feedback, inhibiting ovulation. Ethynodiol diacetate also increases cervical mucus viscosity and induces endometrial changes.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between LO MINASTRIN FE and DEMULEN 1/50-28 depend on the specific clinical indication. These are both Combination Oral Contraceptive agents and are not directly interchangeable by dose. A physician or clinical pharmacist should guide any therapeutic switching decisions.
The standard adult dose of LO MINASTRIN FE is: 1 tablet (1 mg norethindrone acetate/20 mcg ethinyl estradiol/ferrous fumarate 75 mg) orally once daily for 28 consecutive days.. The standard adult dose of DEMULEN 1/50-28 is: One tablet orally once daily for 28 consecutive days per cycle.. 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 LO MINASTRIN FE and DEMULEN 1/50-28 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. LO MINASTRIN FE is classified as Category C. Pregnancy category X. Contraindicated in pregnancy due to risk of fetal harm. First trimester use associated with cardiovascular defects, neural tube defects; second/third trimeste. DEMULEN 1/50-28 is classified as Category C. Contraindicated in pregnancy. First trimester: increased risk of neural tube defects, congenital heart defects, and limb reduction defects from progestins. Second and third trimest. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.