Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
LO/OVRAL 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 estrogen-progestin oral contraceptive; suppresses gonadotropin release, primarily FSH and LH, inhibiting ovulation; increases viscosity of cervical mucus, impeding sperm penetration; alters endometrial receptivity.
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,Dysfunctional uterine bleeding,Hormonal contraception
FDA: Prevention of pregnancy,Off-label: Treatment of acne vulgaris, dysmenorrhea, endometriosis-related pain, menstrual irregularity
One tablet (30 mcg ethinyl estradiol, 0.3 mg norgestrel) orally once daily for 28-day cycle (21 active, 7 placebo).
One tablet orally once daily for 28 consecutive days per cycle.
Norgestrel (levonorgestrel): 11-45 hours (mean ~24 hours); ethinyl estradiol: 7-21 hours (mean ~14 hours). Half-life increases slightly with repeated dosing due to saturable metabolism.
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.
Ethinyl estradiol is primarily metabolized by CYP3A4; norgestrel is metabolized via reduction and conjugation; both undergo 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.
Urine (50-60% as conjugated metabolites), feces (30-40% as metabolites), enterohepatic recirculation present.
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.
Levonorgestrel: 97-99% (primarily to sex hormone-binding globulin, SHBG, and albumin); ethinyl estradiol: 97-98% (primarily to albumin, increases SHBG levels).
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.
Levonorgestrel: 1.0-1.3 L/kg; ethinyl estradiol: 2.3-3.0 L/kg. Reflects extensive tissue distribution and binding.
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: levonorgestrel ~100% (first-pass metabolism <10%), ethinyl estradiol 38-48% due to first-pass conjugation in gut wall and liver.
Oral: ethinylestradiol bioavailability ~40-60% due to first-pass metabolism; ethynodiol diacetate bioavailability ~60-80% after oral administration.
No dosage adjustment required for mild to moderate impairment. Not recommended in severe renal impairment (e GFR <30 m L/min/1.73m²) due to limited data.
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 (active liver disease, jaundice, or impaired synthetic function). Use discontinued if hepatic function deteriorates.
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.
Post-menarche adolescents: Same dosing as adults (30 mcg ethinyl estradiol/0.3 mg norgestrel daily). Not indicated pre-menarche.
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 postmenopausal women. Higher risk of thromboembolism and cardiovascular events in women >40 years, especially if smoking or other risk factors.
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 oral contraceptive use; risk increases with age (especially in women over 35 years) and with heavy smoking (≥15 cigarettes/day); 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.
Increased risk of thromboembolic disorders (e.g., MI, stroke, VTE); hepatic adenoma; risk of breast cancer; hypertension; gallbladder disease; impaired glucose tolerance; cholestatic jaundice; ocular lesions (e.g., retinal thrombosis); use in pregnancy; fluid retention; hereditary angioedema.
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; cerebrovascular or coronary artery disease; known or suspected breast carcinoma; estrogen-dependent neoplasia; undiagnosed abnormal genital bleeding; known or suspected pregnancy; hepatic adenoma or malignancy; cholestatic jaundice of pregnancy or jaundice with prior pill use; active liver disease; hypersensitivity to any component; cigarette smoking in women ≥35 years; uncontrolled hypertension; diabetes with vascular involvement; headaches with focal neurological symptoms; major surgery with prolonged immobilization.
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 via CYP3A4 inhibition, but clinical relevance is minimal with low-dose pills. Avoid using St. John's wort, which may decrease contraceptive efficacy.
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 increased risk of major malformations based on epidemiological studies. Second/third trimesters: Exposure may increase risk of fetal liver tumors (rare) and possibly cardiovascular malformations; contraindicated due to feminization of male fetus. Post-market reports: Possible association with neonatal jaundice, cholestasis, and transient hormonal effects.
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.
Contraindicated during breastfeeding due to potential adverse effects on milk production and infant hormonal balance. M/P ratio not established; ethinyl estradiol and norgestrel are excreted into human milk in small amounts but insufficient data on infant exposure.
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 during pregnancy; drug is contraindicated after confirmed pregnancy. Pregnancy-induced changes in pharmacokinetics (increased clearance, volume of distribution) may reduce efficacy, but use is not recommended.
No adjustments; absolute contraindication in pregnancy. Drug should be discontinued immediately upon pregnancy diagnosis. No established safe dose in pregnancy.
Lo/Ovral is a low-dose combined oral contraceptive containing ethinyl estradiol and norgestrel. Not recommended for use in women with BMI > 35 kg/m² due to increased thromboembolic risk. Advise consistent daily timing within a 3-hour window to maintain efficacy. Missed pill management: if one pill is missed >12 hours late, take missed pill and continue with next pill at normal time; if two or more pills are missed, take the most recent missed pill and use backup contraception for 7 days. Consider CYP3A4 inducers (e.g., rifampin, St. John's wort) that may reduce efficacy.
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 every day.,Do not skip pills; if you miss a pill, follow the missed pill instructions in the package insert.,Use backup contraception (e.g., condoms) if you vomit or have severe diarrhea within 4 hours of taking a pill.,Avoid smoking, especially if over 35 years old, as it increases risk of serious cardiovascular side effects.,Tell your healthcare provider about all medications and supplements you take, as some may interfere with birth control effectiveness.,Lo/Ovral does not protect against HIV or other sexually transmitted infections.,Store at room temperature away from moisture and heat.
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 vs DEMULEN 1/50-28, answered by our medical review team.
LO/OVRAL is a Combination Oral Contraceptive that works by Combination estrogen-progestin oral contraceptive; suppresses gonadotropin release, primarily FSH and LH, inhibiting ovulation; increases viscosity of cervical mucus, impeding sperm penetration; alters endometrial receptivity.. 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 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 is: One tablet (30 mcg ethinyl estradiol, 0.3 mg norgestrel) orally once daily for 28-day cycle (21 active, 7 placebo).. 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 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 is classified as Category C. First trimester: No increased risk of major malformations based on epidemiological studies. Second/third trimesters: Exposure may increase risk of fetal liver tumors (rare) and pos. 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.