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
Oral Contraceptive/Prescription

NORMINEST FE

NORMINEST FE

Clinical safety rating

caution

Comprehensive clinical and safety monograph for NORMINEST FE (NORMINEST FE).


Mechanism of Action

Combination oral contraceptive containing norethindrone acetate (progestin) and ethinyl estradiol (estrogen). Inhibits ovulation via suppression of gonadotropins (FSH, LH). Increases cervical mucus viscosity, reducing sperm penetration. Norethindrone acetate is metabolized to norethindrone, which binds to progesterone receptors; ethinyl estradiol binds to estrogen receptors, providing contraceptive effect and cycle control.

What the body does with it

MetabolismNorethindrone acetate: extensively metabolized in the liver via reduction and conjugation. Active metabolite: norethindrone. Ethinyl estradiol: metabolized via CYP3A4 and conjugation (glucuronidation and sulfation). Undergoes enterohepatic recirculation.
ExcretionRenal 60-80% as metabolites, fecal 20-30% via bile, unchanged drug <5%.
Half-lifeNorethindrone: 7-8 hours; ethinyl estradiol: 13-14 hours. Clinical context: steady-state in 5-7 days.
Protein bindingNorethindrone: 61% bound to albumin, 36% to SHBG; ethinyl estradiol: 98% bound to albumin.
Volume of DistributionNorethindrone: 3.6 ± 0.7 L/kg; ethinyl estradiol: 1.8 ± 0.5 L/kg. Reflects distribution to tissues.
BioavailabilityNorethindrone: 64% (oral); ethinyl estradiol: 48% (oral) due to first-pass metabolism.
Onset of ActionOral: contraceptive effect requires 7 days of consistent use; menstrual regulation within 7-10 days.
Duration of ActionOral: 24-hour dosing interval; withdrawal bleeding typically occurs 2-3 days after last active pill.
Molecular WeightNorethindrone: 298.42 Da; Ethinyl estradiol: 296.40 Da

Classification & Brands

Dosing & administration

1 tablet orally once daily, starting on day 1 of menstrual cycle; each tablet contains norethindrone acetate 1 mg and ethinyl estradiol 20 mcg (21 active tablets) followed by 7 ferrous fumarate tablets.

Dosage formTABLET
Renal impairmentNo dose adjustment required for mild to moderate impairment; contraindicated in severe renal impairment or acute renal failure due to potential fluid retention.
Liver impairmentContraindicated in Child-Pugh class B or C; use with caution in Child-Pugh class A; monitor liver function.
Pediatric useNot indicated for use before menarche; for adolescents, same dosing as adults after menarche; safety and efficacy established in females of reproductive age.
Geriatric useNot indicated for use in postmenopausal women; no dosing studies in geriatric population; use not recommended.

Use during pregnancy

1st trimesterAvoid during first trimester due to risk of fetal harm; pregnancy should be excluded before initiation. Combination oral contraceptives are contraindicated in pregnancy.
2nd trimesterNot indicated for use during pregnancy. If inadvertently taken, discontinue immediately.
3rd trimesterNot indicated for use during pregnancy. May increase risk of jaundice and fluid retention in the neonate.

Clinical note

Comprehensive clinical and safety monograph for NORMINEST FE (NORMINEST FE).

Placental transferEstrogens and progestins cross the placenta; evidence of transfer to fetus based on drug class and animal studies.
BreastfeedingCombination hormonal contraceptives like NORMINEST FE may reduce milk production and pass into breast milk. Use alternative contraception during breastfeeding, especially in the early postpartum period.
Lactation RatingL4 (Possibly Hazardous)
Teratogenic RiskNORMINEST FE (norethindrone/ethinyl estradiol) is contraindicated in pregnancy. First trimester: No increased risk of major birth defects from inadvertent exposure in large epidemiologic studies, but increased risk of cardiovascular and limb anomalies reported with higher doses. Second/third trimester: Androgenic effects causing clitoromegaly, labial fusion, and potential for impaired fetal growth. Postnatal: Possible long-term neurodevelopmental effects.
Fetal MonitoringMonitor blood pressure, liver function, glucose tolerance, and signs of thrombophlebitis. Fetal monitoring via ultrasound for growth restriction and anomalies if exposure occurs during organogenesis.
Fertility EffectsReversible suppression of ovulation; no permanent impact on fertility after discontinuation. Return to normal fertility typically occurs within 1-3 cycles.

Warnings & precautions

■ FDA Black Box Warning

Cigarette smoking increases risk of serious cardiovascular events from combination oral contraceptives. Risk increases with age and heavy smoking (≥15 cigarettes/day). Women over 35 who smoke should not use this product.

Side Effect Profile

Serious Effects

Absolute Contraindications

Thrombophlebitis or thromboembolic disordersCurrent or past history of cerebrovascular diseaseCoronary artery diseaseActive liver disease or liver tumorsKnown or suspected breast cancerEndometrial cancer or other estrogen-dependent neoplasiaUndiagnosed abnormal genital bleedingKnown or suspected pregnancyHypersensitivity to any componentCholestatic jaundice of pregnancy or jaundice with prior pill useHepatic adenoma or carcinomaMajor surgery with prolonged immobilization

Clinical Precautions

PrecautionsThrombotic disorders: venous thromboembolism, arterial thromboembolism, stroke, myocardial infarction., Cigarette smoking increases cardiovascular risk; advise not to smoke., Elevated blood pressure: monitor regularly., Gallbladder disease: increased risk of cholelithiasis., Liver tumors: benign and malignant hepatic adenomas reported., Carbohydrate and lipid metabolism: monitor in diabetics and those with dyslipidemia., Headache: may worsen or initiate migraine; discontinue if new headache pattern or persistent., Bleeding irregularities: breakthrough bleeding and spotting are common; evaluate if persistent., Ocular effects: retinal thrombosis may cause partial or complete loss of vision; discontinue if proptosis, diplopia, or papilledema., Depression: discontinue if severe or persistent., Iron overload: contraindicated in patients with hemosiderosis or hemochromatosis (due to ferrous fumarate).
Food/DietaryNo significant food interactions with the hormonal components. Iron tablets may cause gastrointestinal upset; taking with food may reduce nausea but can decrease iron absorption. Avoid high-calcium foods with iron pills. Grapefruit juice may increase estrogen levels; limit intake.

Clinical Tips & Counseling

Clinical PearlsNorminest FE is a combination oral contraceptive containing norethindrone and ethinyl estradiol with ferrous fumarate (iron) in the placebo pills. The iron component does not provide contraception. Breakthrough bleeding is more common with low-dose formulations. Patients should be counseled that the iron pills are not active hormonal pills. Monitor for signs of thromboembolism, especially in smokers over 35 years old.
Patient AdviceTake one pill daily at the same time each day. Do not skip doses. · The last row of pills (typically brown) are iron tablets and do not provide contraception. · Use a backup method (e.g., condoms) if you miss two or more active pills. · Common side effects include nausea, breast tenderness, and spotting between periods. · Seek immediate medical attention for leg pain, shortness of breath, or severe headache. · Smoking increases risk of serious cardiovascular side effects, especially if you are over 35.

NORMINEST FE 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

ADQUEYAFIRMELLEALTAVERAALYACEN 1/35ALYACEN 7/7/7

External sources

DailyMed (NIH) PubMed OpenFDA