Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
DASETTA 1/35 vs AFIRMELLE
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Combination of an estrogen (ethinyl estradiol) and a progestin (norethindrone). Suppresses gonadotropin-releasing hormone (Gn RH) from the hypothalamus, reducing luteinizing hormone (LH) and follicle-stimulating hormone (FSH) secretion from the pituitary, thereby inhibiting ovulation. Additionally, induces changes in cervical mucus (impenetrability to sperm) and endometrium (reduced likelihood of implantation).
Combination oral contraceptive containing ethinyl estradiol and levonorgestrel. Inhibits ovulation by suppressing gonadotropin release (FSH and LH). Also increases cervical mucus viscosity and alters endometrial receptivity.
Prevention of pregnancy in women who elect to use oral contraceptives as a method of contraception
Prevention of pregnancy (FDA-approved)
One tablet orally once daily, each containing 1 mg norethindrone acetate and 35 mcg ethinyl estradiol.
One tablet (0.1 mg levonorgestrel, 0.02 mg ethinyl estradiol) orally once daily for 21 days, followed by 7 days of placebo.
Norethindrone: 5-14 hours (mean 8 hours); ethinyl estradiol: 10-20 hours (mean 14 hours). Clinical context: steady-state achieved within 5-7 days.
Terminal elimination half-life: 12–15 hours. Steady-state achieved within 5 days with Q12H dosing.
Ethinyl estradiol is metabolized primarily by CYP3A4, with sulfation and glucuronidation also involved. Norethindrone is metabolized via reduction and conjugation (sulfate and glucuronide conjugates) and also undergoes oxidation by CYP3A4.
Ethinyl estradiol undergoes first-pass metabolism in gut and liver via CYP3A4, with conjugation to sulfate and glucuronide. Levonorgestrel is metabolized primarily by CYP3A4 to reduced and hydroxylated metabolites, then conjugated.
Renal (55-60% as metabolites, 25-30% as unchanged drug and conjugates), biliary/fecal (30-35% as metabolites).
Renal: 50% as unchanged drug and metabolites; fecal: 40% as metabolites; biliary: ~10% as glucuronide conjugates.
Norethindrone: 80-90% bound to SHBG and albumin; ethinyl estradiol: 97-98% bound to albumin.
~99% bound to serum albumin and sex hormone-binding globulin.
Norethindrone: 4.0 L/kg (distribution extensive into tissues); ethinyl estradiol: 4.5 L/kg (high tissue binding).
2.8 L/kg (apparent Vd), indicating extensive tissue distribution.
Oral: norethindrone 50-77% (first-pass metabolism); ethinyl estradiol 38-48% (first-pass metabolism).
Oral: ~70% due to first-pass metabolism.
No adjustment required for mild to moderate renal impairment. Use with caution in severe renal impairment (GFR <30 m L/min) due to potential fluid retention.
No dose adjustment required for mild to moderate renal impairment. Not recommended for use in end-stage renal disease.
Contraindicated in acute hepatic disease or hepatocellular carcinoma. For mild hepatic impairment (Child-Pugh A), use with caution; no specific dose adjustment established. Avoid in moderate to severe (Child-Pugh B or C) due to impaired hormone clearance.
Contraindicated in acute hepatic disease or severe (Child-Pugh C) hepatic impairment. Use with caution in mild to moderate hepatic impairment; monitor liver function.
Not indicated for use before menarche. For postmenarchal adolescents, dosing is same as adults: one tablet orally once daily.
Not indicated for use before menarche. Post-menarche: same as adult dosing (one tablet daily) based on adult clinical trials.
Not indicated for use after menopause. No specific geriatric dosing recommendations; consider risk of thrombotic events and comorbidities.
Not indicated for use in postmenopausal women; no specific dose adjustment required in healthy elderly, but limited data available.
Cigarette smoking increases the risk of serious cardiovascular adverse effects from combination oral contraceptives (COCs). This risk increases with age, particularly in women over 35 years of age, and with the number of cigarettes smoked. For this reason, COCs should not be used by women who are over 35 years of age and smoke.
Cigarette smoking increases risk of serious cardiovascular events from combination oral contraceptive use. Risk increases with age (especially in women over 35) and with heavy smoking (15+ cigarettes/day). Women who use combination hormonal contraceptives should be strongly advised not to smoke.
Thrombotic and other vascular events (e.g., venous thromboembolism, myocardial infarction, stroke),Liver disease (e.g., hepatic adenomas, hepatocellular carcinoma),Elevated blood pressure,Carbohydrate and lipid metabolic effects,Gallbladder disease,Dermatologic conditions (e.g., chloasma, photosensitivity),Ocular effects (e.g., retinal thrombosis),Depression,Cervical cancer screening,Hereditary angioedema,Interference with laboratory tests
Thrombotic disorders (venous thromboembolism, stroke, myocardial infarction),Cigarette smoking (increases cardiovascular risk),Hypertension (especially in women with renal disease or migraines),Gallbladder disease,Hepatic neoplasia (benign and malignant),Carbohydrate and lipid metabolism effects,Ocular lesions (retinal thrombosis),Depressed mood or depression,Uterine bleeding irregularities,Reduced efficacy with hepatic enzyme inducers
Thrombophlebitis or thromboembolic disorders (current or history),Cerebrovascular or coronary artery disease (current or history),Known or suspected breast carcinoma,Undiagnosed abnormal genital bleeding,Cholestatic jaundice of pregnancy or jaundice with prior oral contraceptive use,Hepatic adenoma or carcinoma (current or history),Known or suspected pregnancy,Active liver disease (e.g., acute viral hepatitis, severe cirrhosis),Hypersensitivity to any component of the product,Use of Hepatitis C drug combinations containing ombitasvir/paritaprevir/ritonavir, with or without dasabuvir
Thrombophlebitis or thromboembolic disorders (current or history),Cerebrovascular or coronary artery disease (current or history),Known or suspected breast cancer, endometrial cancer, or other estrogen-dependent neoplasia,Undiagnosed abnormal genital bleeding,Cholestatic jaundice of pregnancy or jaundice with prior oral contraceptive use,Hepatic adenoma or carcinoma (current or history),Known or suspected pregnancy,Hypersensitivity to any component of the product,Heavy smoking (≥15 cigarettes/day) in women over 35
No specific food interactions are known for DASETTA 1/35. However, grapefruit juice may increase estrogen levels by inhibiting CYP3A4 metabolism; consider limiting grapefruit intake. St. John's Wort can reduce efficacy of oral contraceptives and should be avoided.
Grapefruit juice may increase ethinyl estradiol levels; avoid large quantities. No significant food restrictions. Administer with food if GI upset occurs.
Category X. First trimester: Risk of cardiovascular defects and neural tube defects; second and third trimesters: Risk of female genital tract anomalies (e.g., vaginal adenosis, clear cell adenocarcinoma) due to diethylstilbestrol component.
Pregnancy category X. Contraindicated in pregnancy due to risk of fetal harm. First trimester: exposure associated with congenital anomalies (e.g., cardiovascular, neural tube defects). Second and third trimesters: increased risk of fetal growth restriction, preterm birth, and neonatal respiratory distress. Postnatal: possible long-term developmental effects.
Contraindicated. Diethylstilbestrol is excreted in breast milk; M/P ratio unknown. Potential estrogenic effects in infants. Alternative contraception recommended.
Contraindicated during breastfeeding. Small amounts of ethinyl estradiol and norethindrone are excreted in breast milk; M/P ratio not well defined. Potential for adverse effects on infant (e.g., jaundice, breast enlargement). May reduce milk production and quality.
Dose adjustments not applicable due to contraindication in pregnancy. No pharmacokinetic studies available to guide dosing.
Contraindicated in pregnancy; no dose adjustment recommended. If exposure occurs, immediate discontinuation is required. No pharmacokinetic data support safe use; avoid use entirely.
DASETTA 1/35 is a monophasic combination oral contraceptive containing 1 mg norethindrone and 35 mcg ethinyl estradiol. It is used for contraception and may also regulate menstrual cycles. The pill-free interval is 7 days. Instruct patients to take one tablet daily at the same time. If a pill is missed, follow standard missed pill guidelines: if missed by <24 hours, take it immediately; if by >24 hours, take the missed pill and skip the placebo week. Breakthrough bleeding is common in the first few cycles; consider adjusting estrogen dose if persistent. Counsel about increased thromboembolic risk in smokers >35 years old.
Afirmelle (levonorgestrel/ethinyl estradiol) is a combined oral contraceptive. Counsel patients to take at the same time daily to maintain consistent hormone levels. Use back-up contraception if a dose is missed. Monitor for signs of thromboembolism, especially in smokers over 35. Advise that certain antibiotics (e.g., rifampin) and anticonvulsants (e.g., phenytoin) may reduce efficacy. Consider progestin-only pill if contraindications to estrogen exist.
Take one tablet at the same time every day for 21 days, then 7 placebo pills.,Start the pack on the first Sunday after menstruation begins or on the first day of menses.,If you miss a pill, take it as soon as remembered unless >24 hours late; then take two pills the next day.,Use backup contraception (e.g., condoms) if you miss more than one pill or if vomiting/diarrhea occurs within 4 hours of taking a pill.,Report signs of blood clots: sudden leg pain, shortness of breath, chest pain, or headache.,Do not smoke while taking this medication, especially if over 35 years old.,The pill does not protect against sexually transmitted infections.
Take one pill at the same time every day, even if you don't have sex.,If you miss a pill, follow the instructions in the package insert or ask your healthcare provider.,Use a backup method (like condoms) if you start late or miss pills.,This medication does not protect against HIV or other sexually transmitted infections.,Common side effects include nausea, breast tenderness, and breakthrough bleeding.,Seek medical help if you have symptoms of a blood clot: sudden chest pain, leg swelling, or shortness of breath.,Smoking while on this pill increases your risk of serious cardiovascular events.
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 DASETTA 1/35 vs AFIRMELLE, answered by our medical review team.
DASETTA 1/35 is a Oral Contraceptive that works by Combination of an estrogen (ethinyl estradiol) and a progestin (norethindrone). Suppresses gonadotropin-releasing hormone (Gn RH) from the hypothalamus, reducing luteinizing hormone (LH) and follicle-stimulating hormone (FSH) secretion from the pituitary, thereby inhibiting ovulation. Additionally, induces changes in cervical mucus (impenetrability to sperm) and endometrium (reduced likelihood of implantation).. AFIRMELLE is a Combined Oral Contraceptive that works by Combination oral contraceptive containing ethinyl estradiol and levonorgestrel. Inhibits ovulation by suppressing gonadotropin release (FSH and LH). Also increases cervical mucus viscosity and alters endometrial receptivity.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between DASETTA 1/35 and AFIRMELLE depend on the specific clinical indication. These are agents from distinct pharmacological classes and are not directly interchangeable by dose. A physician or clinical pharmacist should guide any therapeutic switching decisions.
The standard adult dose of DASETTA 1/35 is: One tablet orally once daily, each containing 1 mg norethindrone acetate and 35 mcg ethinyl estradiol.. The standard adult dose of AFIRMELLE is: One tablet (0.1 mg levonorgestrel, 0.02 mg ethinyl estradiol) orally once daily for 21 days, followed by 7 days of placebo.. 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 DASETTA 1/35 and AFIRMELLE 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. DASETTA 1/35 is classified as Category C. Category X. First trimester: Risk of cardiovascular defects and neural tube defects; second and third trimesters: Risk of female genital tract anomalies (e.g., vaginal adenosis, cl. AFIRMELLE is classified as Category C. Pregnancy category X. Contraindicated in pregnancy due to risk of fetal harm. First trimester: exposure associated with congenital anomalies (e.g., cardiovascular, neural tube defe. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.