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Oral Contraceptive/Prescription

NORTREL 7/7/7

NORTREL 7/7/7

Clinical safety rating

caution

Comprehensive clinical and safety monograph for NORTREL 7/7/7 (NORTREL 7/7/7).


Mechanism of Action

Combination estrogen-progestin oral contraceptive. Suppresses gonadotropin release, inhibiting ovulation. Increases cervical mucus viscosity and alters endometrial receptivity.

What the body does with it

MetabolismEthinyl estradiol: primarily metabolized by CYP3A4; undergoes first-pass metabolism. Norethindrone: metabolized by reduction and conjugation; primarily via CYP3A4.
ExcretionRenal excretion of metabolites (primarily ethinyl estradiol and norelgestromin conjugates) accounts for approximately 50% of elimination; fecal/biliary excretion accounts for the remainder (about 35-40% fecal, 10-15% biliary).
Half-lifeNorelgestromin terminal half-life is approximately 28 hours; ethinyl estradiol terminal half-life is approximately 17 hours. The extended half-life supports once-weekly dosing.
Protein bindingNorelgestromin is 99% bound primarily to albumin and sex hormone-binding globulin; ethinyl estradiol is 98% bound primarily to albumin.
Volume of DistributionNorelgestromin apparent Vd/F is approximately 2.1 L/kg; ethinyl estradiol apparent Vd/F is approximately 5.5 L/kg, indicating extensive tissue distribution.
BioavailabilityTransdermal bioavailability of norelgestromin and ethinyl estradiol is approximately 60-65% relative to oral administration due to avoidance of first-pass metabolism.
Onset of ActionClinical contraceptive effect is achieved within 7 days of initial application if started on the first day of menstruation; ovulation inhibition is established within the first week.
Duration of ActionEach transdermal patch provides contraceptive efficacy for 7 days; three consecutive weekly patches are used followed by a 7-day patch-free interval.
Molecular Weight340.46

Classification & Brands

Dosing & administration

One tablet orally once daily, taken at the same time each day. Each tablet contains norethindrone 0.5 mg/ethinyl estradiol 35 mcg for days 1-7, norethindrone 0.75 mg/ethinyl estradiol 35 mcg for days 8-14, and norethindrone 1 mg/ethinyl estradiol 35 mcg for days 15-21, followed by 7 placebo tablets.

Dosage formTABLET
Renal impairmentNo dose adjustment recommended for mild to moderate renal impairment. Contraindicated in severe renal impairment or acute renal failure due to potential for decreased drug elimination and hormonal alterations.
Liver impairmentContraindicated in acute hepatic disease or severe hepatic insufficiency (Child-Pugh class C). For Child-Pugh class A or B, use with caution; consider alternative contraception due to possible impaired hormone metabolism. No specific dose adjustment guidelines available.
Pediatric useSafety and efficacy in postmenarchal pediatric patients have been established. Dose is the same as for adults: one tablet orally once daily following the 28-day regimen.
Geriatric useNot indicated for use in postmenopausal women. No studies in geriatric population; use is not appropriate due to lack of need for contraception.

Use during pregnancy

1st trimesterAvoid; combination oral contraceptives may increase risk of congenital anomalies, particularly cardiac defects, during the first trimester. Use only if clearly needed after careful risk-benefit assessment.
2nd trimesterAvoid; contains estrogen and progestin; may be associated with increased risk of intrauterine growth restriction and preterm delivery. Not recommended during pregnancy.
3rd trimesterAvoid; estrogen-containing contraceptives can cause adverse effects on fetal development, including potential masculinization of female fetuses with progestins. Should not be used during pregnancy.

Clinical note

Comprehensive clinical and safety monograph for NORTREL 7/7/7 (NORTREL 7/7/7).

Placental transferEstrogens and progestins cross the placenta. Norethindrone and ethinyl estradiol have been shown to transfer to the fetus, with potential for adverse effects.
BreastfeedingExcreted in breast milk in small amounts; may reduce milk production and affect infant hormone levels. Use during breastfeeding is generally not recommended. Consider progestin-only alternatives if contraception is needed.
Lactation RatingL3 (Moderately Safe) - Limited data suggests minimal risk, but estrogen-containing products may reduce milk supply.
Teratogenic RiskFirst trimester: No known association with major congenital anomalies based on population data. However, exposure to ethinyl estradiol and norethindrone acetate is not recommended during pregnancy due to theoretical risks from hormonal exposure. Second and third trimesters: Not indicated for use; hormonal contraceptives should be discontinued if pregnancy occurs. No evidence of fetal harm from inadvertent use early in pregnancy.
Fetal MonitoringPregnancy test before initiation and if pregnancy suspected. Monitor for signs of thrombotic events (e.g., DVT, PE) and hypertension. No specific fetal monitoring required unless exposure occurs during pregnancy.
Fertility EffectsSuppresses ovulation via combined hormonal activity. No permanent impairment of fertility; normal fertility returns upon discontinuation. No evidence of long-term adverse effects on oocyte or sperm quality.

Warnings & precautions

■ FDA Black Box Warning

Cigarette smoking increases risk of serious cardiovascular events. Use is contraindicated in women over 35 who smoke.

Side Effect Profile

Serious Effects

Absolute Contraindications

Pregnancy or suspected pregnancyHistory of thromboembolic disorders or thrombophlebitisCerebrovascular or coronary artery diseaseKnown or suspected breast carcinomaEstrogen-dependent neoplasiaUndiagnosed abnormal genital bleedingKnown or suspected pregnancyHepatic adenoma or carcinomaActive liver disease or impaired liver functionHypersensitivity to any component

Clinical Precautions

PrecautionsIncreased risk of thromboembolic disorders, myocardial infarction, stroke, hepatic neoplasia, gallbladder disease. Discontinue if jaundice, visual disturbances, or migraine occurs. Blood pressure should be monitored.
Food/DietaryNo significant food interactions. Grapefruit juice may slightly increase estrogen exposure but not considered clinically relevant. Avoid herbal supplements such as St. John's wort, which can reduce contraceptive efficacy.

Clinical Tips & Counseling

Clinical PearlsNORTREL 7/7/7 is a triphasic oral contraceptive. The 7/7/7 dosing (7 days of 35 mcg EE/0.5 mg norethindrone, 7 days of 35 mcg EE/0.75 mg norethindrone, 7 days of 35 mcg EE/1 mg norethindrone) mimics natural cycle. Missed dose management: if missed one active pill, take as soon as remembered; if missed two or more, use backup contraception for 7 days and consider emergency contraception. Breakthrough bleeding is common in first 3 cycles. Drug interactions: rifampin, certain anticonvulsants, and some antibiotics may reduce efficacy. Contraindicated in women with migraines with aura, history of DVT/PE, active liver disease, or breast cancer. Monitor blood pressure at baseline and follow-up.
Patient AdviceTake one pill daily at the same time each day, following the 7/7/7 sequence. · Missed pill instructions: if you miss one active pill, take it as soon as you remember and continue the pack; if you miss two or more active pills, take the most recent missed pill, discard others, use backup contraception for 7 days, and consider emergency contraception. · Common side effects include nausea, breast tenderness, breakthrough bleeding, and mood changes; these often improve after 3 cycles. · Seek emergency care if you experience leg pain/swelling, chest pain, sudden severe headache, or vision changes, which may signal a blood clot. · Smoking increases the risk of serious cardiovascular side effects, especially if you are over 35 years old. · Tell your doctor about all medications you take, including antibiotics and herbal supplements like St. John's wort. · If you miss a period, take a pregnancy test and contact your doctor.

NORTREL 7/7/7 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