Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
LO/OVRAL-28 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 of norgestrel, a progestin, and ethinyl estradiol, an estrogen; suppresses gonadotropin secretion (FSH and LH) primarily via progestational activity, inhibiting ovulation; increases cervical mucus viscosity, impeding sperm penetration; alters endometrial development, 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,Oral contraceptive
FDA: Prevention of pregnancy,Off-label: Treatment of acne vulgaris, dysmenorrhea, endometriosis-related pain, menstrual irregularity
One tablet orally once daily for 28 days. Each tablet contains 0.3 mg norgestrel and 0.03 mg ethinyl estradiol. Active tablets (21 days) followed by placebo tablets (7 days).
One tablet orally once daily for 28 consecutive days per cycle.
Norgestrel: 20-40 hours; Ethinyl estradiol: 13-27 hours. Steady-state achieved after 3-5 half-lives.
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 for ethinyl estradiol; norgestrel metabolized via reduction and conjugation.
Ethinyl estradiol: CYP3A4; undergoes first-pass metabolism with sulfation and glucuronidation. Ethynodiol diacetate: Deacetylated to norethynodrel, then extensively metabolized via reduction and conjugation.
Renal (approx. 50% as metabolites, <1% unchanged); biliary/fecal (approx. 50% as metabolites).
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.
Norgestrel: 93-99% (primarily SHBG and albumin); Ethinyl estradiol: 97-98% (primarily albumin and SHBG).
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.
Norgestrel: 3.0 L/kg; Ethinyl estradiol: 4.0 L/kg.
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: Norgestrel 85-90%; Ethinyl estradiol 38-48% due to first-pass metabolism.
Oral: ethinylestradiol bioavailability ~40-60% due to first-pass metabolism; ethynodiol diacetate bioavailability ~60-80% after oral administration.
No dosage adjustment required for renal impairment. However, use with caution in patients with renal dysfunction due to potential fluid retention.
No dosage adjustment required for renal impairment. Use is not recommended in patients with severe renal impairment due to potential adverse effects.
Contraindicated in patients with Child-Pugh Class B or C cirrhosis. For Child-Pugh Class A, use with caution; limited data, but no specific dose adjustment recommended.
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 before menarche. For post-menarchal adolescents, the same dosing as adults: one tablet orally daily for 28-day cycles.
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 in postmenopausal women. No geriatric-specific dosing; not for use in elderly due to lack of need for contraception after menopause.
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 and smoking intensity (especially in women over 35). Women should be strongly advised not to smoke.
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 (e.g., venous thromboembolism, stroke, myocardial infarction); hepatic neoplasia; hypertension; gallbladder disease; carbohydrate/lipid effects; ocular lesions; breakthrough bleeding; missed periods; ectopic pregnancy risk; lactation; depression.
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; history of deep vein thrombosis or pulmonary embolism; cerebrovascular or coronary artery disease; known or suspected breast carcinoma; 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.
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 does not notably affect ethinyl estradiol levels, but consistent intake is recommended to maintain uniform hormone levels. Avoid excessive alcohol consumption as it may impair liver function and alter hormone metabolism.
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.
First trimester: No known association with major congenital anomalies, but small increased risk of cardiovascular defects and limb reduction defects reported in some studies. Second/third trimesters: Use not recommended due to potential adverse effects on fetal development including virilization of female fetus and hepatic adenoma; contraindicated in known pregnancy.
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.
Enters breast milk in small amounts; estrogen and progestin may reduce milk production and composition. M/P ratio not established. Generally avoided during breastfeeding due to theoretical risks; low-dose progestin-only contraception preferred.
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.
Contraindicated in pregnancy; no dose adjustments applicable as use is not recommended. Pharmacokinetic changes in pregnancy include increased clearance of ethinyl estradiol and norgestrel, but pregnancy contraindication precludes dose modification.
No adjustments; absolute contraindication in pregnancy. Drug should be discontinued immediately upon pregnancy diagnosis. No established safe dose in pregnancy.
LO/OVRAL-28 is a combination oral contraceptive containing norgestrel and ethinyl estradiol. It is indicated for pregnancy prevention. The 28-day regimen includes 21 active pills and 7 placebo pills. Counsel patients to take at the same time daily. Breakthrough bleeding is common in the first few cycles. If a dose is missed, follow the specific package instructions. Anti-infectives like rifampin may reduce efficacy; additional contraception is recommended.
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 pill daily at the same time each day.,If you miss a pill, refer to the package insert for instructions; use backup contraception if needed.,Common side effects include nausea, breast tenderness, and spotting, which usually improve after a few cycles.,Smoking increases risk of serious cardiovascular side effects; do not smoke while taking this medication.,Inform your healthcare provider if you have a history of blood clots, migraines with aura, or liver disease.
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/OVRAL-28 vs DEMULEN 1/50-28, answered by our medical review team.
LO/OVRAL-28 is a Combination Oral Contraceptive that works by Combination of norgestrel, a progestin, and ethinyl estradiol, an estrogen; suppresses gonadotropin secretion (FSH and LH) primarily via progestational activity, inhibiting ovulation; increases cervical mucus viscosity, impeding sperm penetration; alters endometrial development, 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/OVRAL-28 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/OVRAL-28 is: One tablet orally once daily for 28 days. Each tablet contains 0.3 mg norgestrel and 0.03 mg ethinyl estradiol. Active tablets (21 days) followed by placebo tablets (7 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/OVRAL-28 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/OVRAL-28 is classified as Category C. First trimester: No known association with major congenital anomalies, but small increased risk of cardiovascular defects and limb reduction defects reported in some studies. Secon. 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.