Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
MODICON 28 vs DEMULEN 1/35-28
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Combination hormonal contraceptive: ethinyl estradiol suppresses gonadotropin release, inhibiting ovulation; norethindrone induces changes in cervical mucus and endometrium, impeding sperm penetration and implantation.
Combination estrogen-progestin contraceptive; suppresses gonadotropin release, inhibiting ovulation; increases cervical mucus viscosity, impeding sperm penetration; alters endometrial receptivity.
Prevention of pregnancy
Prevention of pregnancy
One tablet orally once daily, each tablet containing 0.035 mg ethinyl estradiol and 0.4 mg norethindrone, taken at the same time each day for 21 days followed by 7 days of placebo tablets.
One tablet (contains 1 mg ethynodiol diacetate and 35 mcg ethinyl estradiol) orally once daily at the same time each day for 21 days, followed by 7 days of placebo or no tablets.
Terminal elimination half-life: 13-19 hours (mean 16 hours) for norethindrone; steady state achieved within 5-7 days.
Ethinyl estradiol: 17.4 ± 5.6 h (terminal); norethindrone: 10.9 ± 1.6 h (terminal); clinically, steady-state achieved within 5-7 days.
Ethinyl estradiol undergoes hepatic metabolism via CYP3A4; norethindrone is metabolized primarily via reduction and conjugation, with involvement of CYP3A4.
Ethinylestradiol undergoes hepatic metabolism via CYP3A4; norethindrone undergoes reduction and conjugation in the liver.
Renal: 50-60% as metabolites, fecal: 40-50% as metabolites, with enterohepatic circulation; less than 1% unchanged in urine.
Renal 50% (metabolites), fecal 50% (biliary elimination of conjugates).
Norethindrone: 61-67% bound to SHBG and albumin (55% to SHBG, 45% to albumin); ethinyl estradiol: 97-98% bound to albumin, not bound to SHBG.
Ethinyl estradiol: 97-98% bound to albumin; norethindrone: 93% bound to albumin and SHBG.
Norethindrone: Vd approximately 4 L/kg (range 2-6 L/kg), indicating extensive tissue distribution; ethinyl estradiol: Vd approximately 2-4 L/kg.
Ethinyl estradiol: 2.3-4.3 L/kg; norethindrone: 4.4 L/kg; indicates extensive tissue distribution.
Oral norethindrone: 45-65% due to first-pass metabolism; ethinyl estradiol: 38-48% oral bioavailability.
Ethinyl estradiol: 40-45% (oral; first-pass metabolism); norethindrone: 64-67% (oral).
No dose adjustment required for mild to moderate renal impairment. Insufficient data for severe renal impairment (Cr Cl <30 m L/min); consider alternative contraception due to potential hormonal accumulation.
No dose adjustment required for mild to moderate renal impairment. Contraindicated in severe renal impairment or acute renal failure.
Contraindicated in acute hepatic disease or severe hepatic impairment (Child-Pugh class C). Use with caution in mild to moderate impairment (Child-Pugh A or B); monitor liver function; consider alternative contraception.
Contraindicated in acute or chronic hepatic dysfunction, including Child-Pugh class A, B, or C. Avoid use if liver function tests are abnormal.
Not indicated for use before menarche. For post-menarche adolescents: same dosing as adults (one tablet daily). Safety and efficacy established in females of reproductive age.
Not indicated for use before menarche. For postmenarchal adolescents, use same dosing as adults (one tablet orally once daily).
Not indicated for use in postmenopausal women. Efficacy for contraception not applicable; no dosing recommendations for this population.
Not indicated for use in postmenopausal women.
Cigarette smoking increases risk of serious cardiovascular events from combination oral contraceptives. 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. Risk increases with age and smoking intensity. Women over 35 who smoke should not use this product.
Thrombotic disorders (thrombophlebitis, venous thromboembolism, cerebrovascular disease, myocardial infarction),Hepatic disease (jaundice, hepatic adenomas),Hypertension,Gallbladder disease,Carbohydrate and lipid effects,Ocular lesions (e.g., retinal thrombosis),Headache (including migraine),Menstrual irregularities/breakthrough bleeding,Depression,Reduced efficacy with enzyme-inducing drugs,Bone mineral density changes,Hereditary angioedema
Increased risk of thromboembolic disorders,Cerebrovascular disease,Myocardial infarction,Hepatic neoplasia,Gallbladder disease,Hypertension,Carbohydrate/lipid effects,Headache,Uterine bleeding,Ocular lesions,Depression
Known or suspected pregnancy,Current or past history of thrombophlebitis or thromboembolic disorders,Cerebrovascular disease,Coronary artery disease,Known or suspected carcinoma of the breast,Carcinoma of the endometrium or other estrogen-dependent neoplasia,Undiagnosed abnormal genital bleeding,Cholestatic jaundice of pregnancy or jaundice with prior oral contraceptive use,Hepatic adenomas or carcinomas,Known or suspected liver disease,Heavy smoking (≥15 cigarettes/day) and age ≥35,Hypersensitivity to any component
Known or suspected pregnancy,Current or past thrombosis,Cerebrovascular or coronary artery disease,Valvular heart disease with complications,Severe hypertension,Diabetes with vascular involvement,Headaches with focal neurological symptoms,Major surgery with prolonged immobilization,Known or suspected breast cancer,Endometrial cancer or other estrogen-dependent neoplasia,Undiagnosed abnormal genital bleeding,Cholestatic jaundice of pregnancy or jaundice with prior pill use,Hepatic adenomas or carcinomas,Active liver disease,Known hypersensitivity to any component
Grapefruit and grapefruit juice may increase ethinyl estradiol levels by inhibiting CYP3A4, but the effect is variable; advise caution or avoid concurrent intake. No other significant food interactions are known. High-fat meals may delay absorption but do not reduce overall efficacy.
No significant food interactions. Grapefruit juice has minimal effect on ethinyl estradiol; no restriction needed. Avoid excessive alcohol, which may impair adherence or increase liver enzymes. St. John's wort reduces contraceptive efficacy and should be avoided.
FDA Pregnancy Category X. First trimester: increased risk of neural tube defects, congenital heart defects, and other malformations due to estrogen/progestin exposure. Second and third trimesters: associated with elevated risks of preterm birth, low birth weight, and neonatal complications. Use contraindicated in pregnancy.
First trimester: Increased risk of neural tube defects, cardiovascular anomalies, and oral clefts (OR ~1.3-1.6). Second/third trimester: Androgenization of female fetus (clitoromegaly, labial fusion) due to progestin component; possible association with hypospadias in males with first-trimester exposure. Avoid use in pregnancy.
Safety: Small amounts of ethinyl estradiol and progestin (norethindrone) are excreted in breast milk. M/P ratio: Not established for this specific combination; ethinyl estradiol M/P ~0.2-0.4. May reduce milk production and alter milk composition. Not recommended during breastfeeding; alternative contraception advised.
Excreted in breast milk; estimated infant dose <1% of maternal dose. M/P ratio not available for ethinyl estradiol/ethynodiol diacetate. May reduce milk production and quality. Use only if benefits outweigh risks; lowest effective dose recommended.
No dose adjustment required as drug is contraindicated in pregnancy. Pharmacokinetic changes during pregnancy (increased hepatic metabolism, volume of distribution) are not relevant due to contraindication. If inadvertent exposure occurs, discontinue drug.
Contraindicated in pregnancy; no dose adjustment applicable. If inadvertently used, discontinue immediately.
MODICON 28 is a combined oral contraceptive containing ethinyl estradiol 0.035 mg and norethindrone 0.5 mg. It is crucial to counsel patients on the importance of taking the pill at the same time daily to maintain consistent hormone levels. The regimen includes 21 active pills followed by 7 placebo pills; during the placebo week, withdrawal bleeding typically occurs. For missed pills: if one pill is missed, take it as soon as remembered and continue schedule; if two or more are missed, take the most recent missed pill and use backup contraception for 7 days. Consider potential drug interactions with antibiotics, anticonvulsants (e.g., carbamazepine, phenytoin), and St. John's wort, which may reduce contraceptive efficacy. Smoking increases risk of serious cardiovascular events, especially in women over 35. Monitor blood pressure at baseline and periodically. Caution in patients with history of thromboembolic disorders, migraine with aura, hypertension, or liver disease.
DEMULEN 1/35-28 (ethinyl estradiol 35 mcg + ethynodiol diacetate 1 mg) is a monophasic combined oral contraceptive. Its progestin has mild androgenic activity, which may be less favorable for acne-prone patients compared to third-generation pills. The 28-day pack includes 21 active pills and 7 inert pills. Counsel patients to take at the same time daily; missed pills increase breakthrough bleeding and pregnancy risk. It may be used off-label for cycle control in patients without contraindications.
Take one pill daily at the same time, preferably after an evening meal or at bedtime to minimize nausea.,The pack contains 21 active (hormone) pills and 7 placebo (reminder) pills; withdrawal bleeding usually occurs during the placebo week.,If you miss a pill, refer to the package insert instructions; use backup contraception (e.g., condoms) if needed.,Use additional non-hormonal contraception during the first 7 days of starting the pill if switching from another method.,Seek immediate medical attention if you experience symptoms of a blood clot, such as sudden leg pain or swelling, chest pain, shortness of breath, or severe headache.,This medication does not protect against sexually transmitted infections (STIs); use condoms for STI prevention.,Inform your healthcare provider of all medications and supplements you take, especially antibiotics, anticonvulsants, and St. John's wort.,Avoid smoking, especially if over 35, as it increases the risk of serious side effects.
Take one pill daily at the same time, preferably after dinner to reduce nausea.,If you miss one pill, take it as soon as remembered; if missed more than one, use backup contraception for 7 days.,Smoking increases risk of blood clots; especially dangerous if over 35 and smokes.,Some antibiotics (e.g., rifampin) and antiseizure medications may reduce effectiveness.,Report any signs of blood clot: sudden leg pain/swelling, chest pain, shortness of breath, or sudden severe headache.,Breakthrough bleeding is common in first 3 cycles; if persistent, contact your healthcare provider.,Do not use if pregnant; if pregnancy occurs, stop immediately.
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 MODICON 28 vs DEMULEN 1/35-28, answered by our medical review team.
MODICON 28 is a Combination Oral Contraceptive that works by Combination hormonal contraceptive: ethinyl estradiol suppresses gonadotropin release, inhibiting ovulation; norethindrone induces changes in cervical mucus and endometrium, impeding sperm penetration and implantation.. DEMULEN 1/35-28 is a Combination Oral Contraceptive that works by Combination estrogen-progestin contraceptive; suppresses gonadotropin release, inhibiting ovulation; increases cervical mucus viscosity, impeding sperm penetration; alters endometrial receptivity.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between MODICON 28 and DEMULEN 1/35-28 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 MODICON 28 is: One tablet orally once daily, each tablet containing 0.035 mg ethinyl estradiol and 0.4 mg norethindrone, taken at the same time each day for 21 days followed by 7 days of placebo tablets.. The standard adult dose of DEMULEN 1/35-28 is: One tablet (contains 1 mg ethynodiol diacetate and 35 mcg ethinyl estradiol) orally once daily at the same time each day for 21 days, followed by 7 days of placebo or no tablets.. 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 MODICON 28 and DEMULEN 1/35-28 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. MODICON 28 is classified as Category C. FDA Pregnancy Category X. First trimester: increased risk of neural tube defects, congenital heart defects, and other malformations due to estrogen/progestin exposure. Second and t. DEMULEN 1/35-28 is classified as Category C. First trimester: Increased risk of neural tube defects, cardiovascular anomalies, and oral clefts (OR ~1.3-1.6). Second/third trimester: Androgenization of female fetus (clitoromeg. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.