Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
DASETTA 1/35 vs ALYACEN 1/35
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 hormonal contraceptive: ethinyl estradiol suppresses gonadotropin release via negative feedback on hypothalamic-pituitary axis; norethindrone induces progestational effects including cervical mucus thickening and endometrial changes, inhibiting ovulation and sperm penetration.
Prevention of pregnancy in women who elect to use oral contraceptives as a method of contraception
Prevention of pregnancy
One tablet orally once daily, each containing 1 mg norethindrone acetate and 35 mcg ethinyl estradiol.
One tablet (norethindrone 1 mg and ethinyl estradiol 35 mcg) orally once daily for 21 consecutive days, followed by 7 days of placebo or no tablets.
Norethindrone: 5-14 hours (mean 8 hours); ethinyl estradiol: 10-20 hours (mean 14 hours). Clinical context: steady-state achieved within 5-7 days.
Norethindrone: 8-11 hours (terminal); ethinyl estradiol: 10-20 hours (terminal). The half-life supports once-daily dosing for oral contraceptive efficacy.
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: primarily hepatic via CYP3A4; norethindrone: hepatic reduction and sulfate conjugation.
Renal (55-60% as metabolites, 25-30% as unchanged drug and conjugates), biliary/fecal (30-35% as metabolites).
Renal excretion of metabolites (primarily ethinyl estradiol and norethindrone conjugates) accounts for approximately 50-60% of elimination; fecal excretion accounts for 30-40%. Unchanged drug excretion is minimal (<5%).
Norethindrone: 80-90% bound to SHBG and albumin; ethinyl estradiol: 97-98% bound to albumin.
Norethindrone: 61% bound to albumin and SHBG; ethinyl estradiol: 97-98% bound to albumin.
Norethindrone: 4.0 L/kg (distribution extensive into tissues); ethinyl estradiol: 4.5 L/kg (high tissue binding).
Norethindrone: 3.8-4.5 L/kg; ethinyl estradiol: 2.0-4.0 L/kg. Large Vd indicates extensive tissue distribution.
Oral: norethindrone 50-77% (first-pass metabolism); ethinyl estradiol 38-48% (first-pass metabolism).
Oral: Norethindrone ~64%, ethinyl estradiol ~38-48% (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. Contraindicated in severe renal impairment or acute renal failure due to potential fluid retention and electrolyte disturbances.
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 patients with hepatic impairment, including Child-Pugh class B or C, due to impaired metabolism of estrogen and progestin. Not recommended in patients with active liver disease or history of liver tumors.
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. For postmenarchal adolescents, same dosing as adults. Safety and efficacy established for contraception; weight-based dosing not applicable.
Not indicated for use after menopause. No specific geriatric dosing recommendations; consider risk of thrombotic events and comorbidities.
Not indicated for use after menopause due to lack of benefit and increased risks (e.g., cardiovascular, thromboembolic events). If used, monitor for fluid retention, hypertension, and glucose intolerance.
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 combined oral contraceptives. Risk increases with age and heavy smoking (≥15 cigarettes/day). Women over 35 who smoke should not use this product.
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 (e.g., DVT, PE, stroke, MI),Cerebrovascular disease,Hepatic neoplasia,Gallbladder disease,Hypertension,Carbohydrate and lipid effects,Ocular lesions,Hereditary angioedema,Chloasma,Menstrual irregularities,Pregnancy exclusion prior to initiation
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
Venous or arterial thrombotic/thromboembolic disease (current or history),Cerebrovascular disease,Coronary artery disease,Known or suspected breast cancer,Endometrial 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,Smoking 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.
No significant food interactions. Grapefruit juice may increase estrogen levels, but clinically not a concern. Avoid excessive alcohol, which may impair liver function and increase estrogen exposure. Maintain a healthy diet, as weight gain is possible.
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. Use of ALYACEN 1/35 (norethindrone/ethinyl estradiol) is contraindicated during pregnancy. First trimester: Increased risk of congenital anomalies, including cardiovascular defects and limb reduction defects. Second/third trimesters: Potential for urogenital abnormalities and feminization of male fetus. Exposure is associated with subsequent development of clear cell adenocarcinoma of vagina/cervix in female offspring (DES-related).
Contraindicated. Diethylstilbestrol is excreted in breast milk; M/P ratio unknown. Potential estrogenic effects in infants. Alternative contraception recommended.
Small amounts of contraceptive steroids and/or metabolites have been identified in breast milk. M/P ratio: Not specifically determined for this combination; ethinyl estradiol M/P ratio ~0.02-0.04. Use may reduce milk production and quality. Breastfeeding not recommended during use. Alternative contraception advised.
Dose adjustments not applicable due to contraindication in pregnancy. No pharmacokinetic studies available to guide dosing.
Contraindicated in pregnancy; no dose adjustments applicable. Discontinue medication immediately upon pregnancy detection.
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.
ALYACEN 1/35 is a combination oral contraceptive containing ethinyl estradiol 35 mcg and norgestimate 1 mg. It is indicated for the prevention of pregnancy and for the treatment of moderate acne vulgaris in females ≥15 years of age who desire an oral contraceptive. Monitor for thromboembolic events, especially in smokers over 35 or those with migraine with aura. Use with caution in patients with liver impairment or history of cholestatic jaundice. The pill-free interval should not exceed 7 days; missed pills increase ovulation risk. Consider non-hormonal backup if vomiting or diarrhea occurs within 4 hours of dosing.
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 tablet daily at the same time each day; do not skip doses.,Use an additional non-hormonal contraceptive (e.g., condoms) if you miss a pill, have vomiting, or diarrhea.,Smoking while on this pill increases the risk of blood clots and stroke, especially if you are over 35.,Contact your healthcare provider immediately if you have chest pain, leg pain/swelling, sudden vision changes, or severe headache.,This medication does not protect against HIV or other sexually transmitted infections.,Store at room temperature, away from moisture and heat.
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 ALYACEN 1/35, 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).. ALYACEN 1/35 is a Oral Contraceptive that works by Combination hormonal contraceptive: ethinyl estradiol suppresses gonadotropin release via negative feedback on hypothalamic-pituitary axis; norethindrone induces progestational effects including cervical mucus thickening and endometrial changes, inhibiting ovulation and sperm penetration.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between DASETTA 1/35 and ALYACEN 1/35 depend on the specific clinical indication. These are both Oral Contraceptive agents 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 ALYACEN 1/35 is: One tablet (norethindrone 1 mg and ethinyl estradiol 35 mcg) orally once daily for 21 consecutive 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.
No direct drug-drug interaction has been formally documented between DASETTA 1/35 and ALYACEN 1/35 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. ALYACEN 1/35 is classified as Category C. Pregnancy category X. Use of ALYACEN 1/35 (norethindrone/ethinyl estradiol) is contraindicated during pregnancy. First trimester: Increased risk of congenital anomalies, including . Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.