Logo

OpiCalc

FavoritesSpecialtiesDrugsGuidelinesMost Used

Quick Access

Favorites
Most Used

All Specialties

OpiCalc Logo
Clinical CalculatorsDrugsGuidelines
SpecsDrugsGuides
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
‌
OpiCalc Logo

OpiCalc

Easy, fast, and private medical tools for clinicians. Always free.

No Login Required
Ready for the Bedside

Resources

About UsEditorial PolicyMedical DisclaimerPrivacy PolicyTerms of UseCookie Policy

Support

Contact Us

Clinical Notice:OpiCalc is not a substitute for professional clinical judgment. Always verify dosages and guidelines.

OpiCalc © 2018-2026

•

All Rights Reserved

Registry Hub
Peer-Reviewed Evidence
HomeDrug RegistryCompareLO MINASTRIN FE vs DEMULEN 1 35 28
Comparative Pharmacology

LO MINASTRIN FE vs DEMULEN 1 35 28 Comparison

Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.

Clinical EssentialsPharmacokineticsSpecial PopulationsSafety & MonitoringPregnancy & LactationClinical Insights
Differential Analysis

LO MINASTRIN FE vs DEMULEN 1/35-28

Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.

View LO MINASTRIN FE Monograph View DEMULEN 1/35-28 Monograph
LO MINASTRIN FE
Combination Oral Contraceptive
Category C
DEMULEN 1/35-28
Combination Oral Contraceptive
Category C
TL;DR — Key Differences
  • Half-life: LO MINASTRIN FE has a half-life of Norethindrone: 8-11 hours; ethinyl estradiol: 12-16 hours. Steady-state achieved after 5-7 days of dosing.; DEMULEN 1/35-28 has Ethinyl estradiol: 17.4 ± 5.6 h (terminal); norethindrone: 10.9 ± 1.6 h (terminal); clinically, steady-state achieved within 5-7 days..
  • No direct drug-drug interaction has been documented between LO MINASTRIN FE and DEMULEN 1/35-28.
  • Pregnancy: LO MINASTRIN FE is rated Category C; DEMULEN 1/35-28 is rated Category C.

Last clinically reviewed: July 2026 · OpiCalc Medical Review Team

Clinical Essentials

LO MINASTRIN FE
DEMULEN 1/35-28
Mechanism of Action
LO MINASTRIN FE

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 1/35-28

Combination estrogen-progestin contraceptive; suppresses gonadotropin release, inhibiting ovulation; increases cervical mucus viscosity, impeding sperm penetration; alters endometrial receptivity.

Indications
LO MINASTRIN FE

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

DEMULEN 1/35-28

Prevention of pregnancy

Standard Dosing
LO MINASTRIN FE

1 tablet (1 mg norethindrone acetate/20 mcg ethinyl estradiol/ferrous fumarate 75 mg) orally once daily for 28 consecutive days.

DEMULEN 1/35-28

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.

Direct Interaction
LO MINASTRIN FE
No Direct Interaction
DEMULEN 1/35-28
No Direct Interaction

Pharmacokinetics

LO MINASTRIN FE
DEMULEN 1/35-28
Half-Life
LO MINASTRIN FE

Norethindrone: 8-11 hours; ethinyl estradiol: 12-16 hours. Steady-state achieved after 5-7 days of dosing.

DEMULEN 1/35-28

Ethinyl estradiol: 17.4 ± 5.6 h (terminal); norethindrone: 10.9 ± 1.6 h (terminal); clinically, steady-state achieved within 5-7 days.

Metabolism
LO MINASTRIN FE

Hepatic via CYP3A4 (ethinyl estradiol) and primarily reduction and conjugation (norethindrone); undergoes first-pass metabolism.

DEMULEN 1/35-28

Ethinylestradiol undergoes hepatic metabolism via CYP3A4; norethindrone undergoes reduction and conjugation in the liver.

Excretion
LO MINASTRIN FE

Renal: 40-50% as conjugated metabolites; fecal: 20-30% via biliary excretion; unchanged drug <1%.

DEMULEN 1/35-28

Renal 50% (metabolites), fecal 50% (biliary elimination of conjugates).

Protein Binding
LO MINASTRIN FE

Norethindrone: 97% bound (primarily to albumin and SHBG); ethinyl estradiol: 98% bound (primarily to albumin).

DEMULEN 1/35-28

Ethinyl estradiol: 97-98% bound to albumin; norethindrone: 93% bound to albumin and SHBG.

VD (L/kg)
LO MINASTRIN FE

Norethindrone: 4 L/kg; ethinyl estradiol: 2-4 L/kg; reflects extensive tissue distribution and binding to sex hormone receptors.

DEMULEN 1/35-28

Ethinyl estradiol: 2.3-4.3 L/kg; norethindrone: 4.4 L/kg; indicates extensive tissue distribution.

Bioavailability
LO MINASTRIN FE

Oral: norethindrone ~64%, ethinyl estradiol ~40-48% due to first-pass metabolism.

DEMULEN 1/35-28

Ethinyl estradiol: 40-45% (oral; first-pass metabolism); norethindrone: 64-67% (oral).

Special Populations

LO MINASTRIN FE
DEMULEN 1/35-28
Renal Adjustments
LO MINASTRIN FE

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.

DEMULEN 1/35-28

No dose adjustment required for mild to moderate renal impairment. Contraindicated in severe renal impairment or acute renal failure.

Hepatic Adjustments
LO MINASTRIN FE

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.

DEMULEN 1/35-28

Contraindicated in acute or chronic hepatic dysfunction, including Child-Pugh class A, B, or C. Avoid use if liver function tests are abnormal.

Pediatric Dosing
LO MINASTRIN FE

Not indicated for use prepubertal. Approved for females of reproductive potential; safety and efficacy in children <12 years not established. Follow adult dosing postmenarche.

DEMULEN 1/35-28

Not indicated for use before menarche. For postmenarchal adolescents, use same dosing as adults (one tablet orally once daily).

Geriatric Dosing
LO MINASTRIN FE

Not indicated for use in postmenopausal women. In women >35 years who smoke, use is contraindicated due to increased cardiovascular risk.

DEMULEN 1/35-28

Not indicated for use in postmenopausal women.

Safety & Monitoring

LO MINASTRIN FE
DEMULEN 1/35-28
Black Box Warnings
LO MINASTRIN FE
FDA Black Box Warning

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.

DEMULEN 1/35-28
FDA Black Box Warning

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.

Warnings/Precautions
LO MINASTRIN FE

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)

DEMULEN 1/35-28

Increased risk of thromboembolic disorders,Cerebrovascular disease,Myocardial infarction,Hepatic neoplasia,Gallbladder disease,Hypertension,Carbohydrate/lipid effects,Headache,Uterine bleeding,Ocular lesions,Depression

Contraindications
LO MINASTRIN FE

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

DEMULEN 1/35-28

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

Adverse Reactions
LO MINASTRIN FE
Data Pending
DEMULEN 1/35-28
Data Pending
Food Interactions
LO MINASTRIN FE

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.

DEMULEN 1/35-28

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.

Pregnancy & Lactation

LO MINASTRIN FE
DEMULEN 1/35-28
Teratogenic Risk
LO MINASTRIN FE

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.

DEMULEN 1/35-28

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.

Lactation Summary
LO MINASTRIN FE

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.

DEMULEN 1/35-28

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.

Pregnancy Dosing
LO MINASTRIN FE

No dose adjustment indicated as drug is contraindicated in pregnancy.

DEMULEN 1/35-28

Contraindicated in pregnancy; no dose adjustment applicable. If inadvertently used, discontinue immediately.

Maternal Safety Status
LO MINASTRIN FE
Category C
DEMULEN 1/35-28
Category C

Clinical Insights

LO MINASTRIN FE
DEMULEN 1/35-28
Clinical Pearls
LO MINASTRIN FE

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 1/35-28

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.

Patient Counseling
LO MINASTRIN FE

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.

DEMULEN 1/35-28

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.

Safety Verification

Known Interactions

LO MINASTRIN FE Risks

No interactions on record

DEMULEN 1/35-28 Risks

No interactions on record

Compare Alternatives

Related Drug Comparisons

Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.

LO MINASTRIN FE vs DEMULEN 1/50-21Combination Oral Contraceptive
DEMULEN 1/35-28 vs DEMULEN 1/50-21Combination Oral Contraceptive
LO MINASTRIN FE vs DEMULEN 1/50-28Combination Oral Contraceptive
DEMULEN 1/35-28 vs DEMULEN 1/50-28Combination Oral Contraceptive
LO MINASTRIN FE vs DESOGENCombination Oral Contraceptive
DEMULEN 1/35-28 vs DESOGENCombination Oral Contraceptive
LO MINASTRIN FE vs EMOQUETTECombination Oral Contraceptive
DEMULEN 1/35-28 vs EMOQUETTECombination Oral Contraceptive
LO MINASTRIN FE vs LARIN 1.5/30Combination Oral Contraceptive
Clinical Q&A

Frequently Asked Questions

Common clinical questions about LO MINASTRIN FE vs DEMULEN 1/35-28, answered by our medical review team.

1. What is the main difference between LO MINASTRIN FE and DEMULEN 1/35-28?

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 1/35-28 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.

2. Which is stronger: LO MINASTRIN FE or DEMULEN 1/35-28?

Potency comparisons between LO MINASTRIN FE 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.

3. What is the standard dosing for LO MINASTRIN FE vs DEMULEN 1/35-28?

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 1/35-28 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.

4. Can you take LO MINASTRIN FE and DEMULEN 1/35-28 together?

No direct drug-drug interaction has been formally documented between LO MINASTRIN FE 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.

5. Are LO MINASTRIN FE and DEMULEN 1/35-28 safe during pregnancy?

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 1/35-28 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.