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Combination Oral Contraceptive/Discontinued

DEMULEN 1/35-28

DEMULEN 1/35-28

Clinical safety rating

caution

Comprehensive clinical and safety monograph for DEMULEN 1/35-28 (DEMULEN 1/35-28).


Mechanism of Action

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

What the body does with it

MetabolismEthinylestradiol undergoes hepatic metabolism via CYP3A4; norethindrone undergoes reduction and conjugation in the liver.
ExcretionRenal 50% (metabolites), fecal 50% (biliary elimination of conjugates).
Half-lifeEthinyl estradiol: 17.4 ± 5.6 h (terminal); norethindrone: 10.9 ± 1.6 h (terminal); clinically, steady-state achieved within 5-7 days.
Protein bindingEthinyl estradiol: 97-98% bound to albumin; norethindrone: 93% bound to albumin and SHBG.
Volume of DistributionEthinyl estradiol: 2.3-4.3 L/kg; norethindrone: 4.4 L/kg; indicates extensive tissue distribution.
BioavailabilityEthinyl estradiol: 40-45% (oral; first-pass metabolism); norethindrone: 64-67% (oral).
Onset of ActionOral: 1-2 h for suppression of gonadotropins; maximal contraceptive effect after 7 days of continuous dosing.
Duration of ActionContraceptive protection requires daily dosing; missed pills reduce efficacy within 24-48 h.
Molecular WeightEthinyl estradiol: 296.4 Da; Ethynodiol diacetate: 384.5 Da

Classification & Brands

Dosing & administration

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.

Dosage formTABLET
Renal impairmentNo dose adjustment required for mild to moderate renal impairment. Contraindicated in severe renal impairment or acute renal failure.
Liver impairmentContraindicated in acute or chronic hepatic dysfunction, including Child-Pugh class A, B, or C. Avoid use if liver function tests are abnormal.
Pediatric useNot indicated for use before menarche. For postmenarchal adolescents, use same dosing as adults (one tablet orally once daily).
Geriatric useNot indicated for use in postmenopausal women.

Use during pregnancy

1st trimesterContraindicated due to risk of congenital defects, particularly cardiovascular and limb anomalies, from female sex hormones.
2nd trimesterContraindicated; may cause fetal harm, though risk is highest in first trimester.
3rd trimesterContraindicated; use in late pregnancy may increase risk of thromboembolism and other adverse effects.

Clinical note

Comprehensive clinical and safety monograph for DEMULEN 1/35-28 (DEMULEN 1/35-28).

Placental transferBoth components cross the placenta; ethinyl estradiol has a placental transfer ratio of approximately 0.5-0.8 relative to maternal serum.
BreastfeedingSmall amounts of ethinyl estradiol and ethynodiol diacetate are excreted in breast milk. Use may reduce milk production and quality; alternative contraception should be considered.
Lactation RatingL4 (Possibly Hazardous)
Teratogenic RiskFirst 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.
Fetal MonitoringMonitor blood pressure, liver function, glucose tolerance, and signs of thromboembolism. If exposure occurs, fetal ultrasound for anomalies; consider echocardiogram if first-trimester exposure.
Fertility EffectsReversible suppression of ovulation. Normal fertility returns within 1-3 cycles after discontinuation. No evidence of permanent impairment.

Warnings & precautions

■ 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.

Side Effect Profile

Serious Effects

Absolute Contraindications

Thromboembolic disordersHistory of deep vein thrombosis or pulmonary embolismCerebral vascular or coronary artery diseaseKnown or suspected breast carcinomaUndiagnosed abnormal genital bleedingPregnancyActive liver disease or impaired liver functionKnown or suspected estrogen-dependent neoplasia

Clinical Precautions

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

Clinical Tips & Counseling

Clinical PearlsDEMULEN 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 AdviceTake 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.

DEMULEN 1/35-28 Interactions

Loading safety data…

This overview is compiled from peer-reviewed clinical sources and FDA labeling. It's here to support — not replace — clinical judgment. Always verify dosing against your institution's current protocols before prescribing.

On this page

Mechanism of ActionDosing & administrationUse during pregnancyWarnings & precautionsDrug interactions

Compare with

DEMULEN 1/50-21DEMULEN 1/50-28DESOGENEMOQUETTELARIN 1.5/30

External sources

DailyMed (NIH) PubMed OpenFDA