Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
HAILEY 1.5/30 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 oral contraceptive containing ethinyl estradiol and desogestrel. Ethinyl estradiol suppresses gonadotropin release via negative feedback on the hypothalamic-pituitary axis; desogestrel, a progestin, inhibits ovulation and alters cervical mucus and endometrial receptivity.
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
Prevention of pregnancy
One tablet (ethinyl estradiol 0.03 mg, levonorgestrel 0.15 mg) orally once daily at the same time each day for 21 days, followed by 7 placebo tablets. For continuous cycling, may take active tablets daily without placebo.
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.
Terminal elimination half-life of ethinyl estradiol is 13-27 hours (mean 17 hours); for norgestimate, active metabolite norelgestromin has half-life 12-30 hours (mean 19 hours). Steady state reached after 7-14 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 undergoes hepatic metabolism primarily via CYP3A4; desogestrel is rapidly metabolized to its active metabolite etonogestrel via hydroxylation and dehydrogenation, further metabolized via CYP2C9 and CYP3A4.
Ethinyl estradiol: primarily hepatic via CYP3A4; norethindrone: hepatic reduction and sulfate conjugation.
Approximately 40% renal (as metabolites), 32% fecal (as metabolites), and <1% unchanged in urine.
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%).
Ethinyl estradiol: ~98% bound to albumin; norelgestromin: ~99% bound to albumin and SHBG.
Norethindrone: 61% bound to albumin and SHBG; ethinyl estradiol: 97-98% bound to albumin.
Ethinyl estradiol: 2.3-4.0 L/kg; norelgestromin: 2.0-3.5 L/kg. Indicates extensive tissue distribution.
Norethindrone: 3.8-4.5 L/kg; ethinyl estradiol: 2.0-4.0 L/kg. Large Vd indicates extensive tissue distribution.
Oral: Ethinyl estradiol 40-55% (first-pass metabolism); norelgestromin: ~80% (as metabolite of norgestimate).
Oral: Norethindrone ~64%, ethinyl estradiol ~38-48% (due to first-pass metabolism).
No dose adjustment required for mild to moderate renal impairment. Not studied in severe impairment, but estrogen metabolites may accumulate; use caution.
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 liver disease or severe hepatic impairment (Child-Pugh C). For mild to moderate (Child-Pugh A or B), use is not recommended due to altered hormone clearance; if used, monitor liver function and consider lower estrogen dose.
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.
Postmenarchal adolescents: Same adult dosing (one tablet daily). Safety and efficacy not established in premenarchal girls.
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 postmenopausal women; contraindicated after menopause due to increased risk of cardiovascular events. No specific geriatric dose.
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 side effects from combination oral contraceptive use. This risk increases with age and with heavy smoking (15 or more cigarettes per day) and is quite marked in women over 35 years of age. Women who use combination oral contraceptives should be strongly advised not to 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.
Increased risk of thromboembolic disorders,Cigarette smoking increases cardiovascular risk,Elevated blood pressure,Gallbladder disease,Hepatic neoplasia,Carbohydrate and lipid effects,Ocular lesions,Headache/migraine,Bleeding irregularities,Depression
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
Active or history of venous thromboembolism,Cerebrovascular disease,Coronary artery disease,Valvular heart disease with complications,Thrombogenic valvulopathies,Major surgery with prolonged immobilization,Diabetes with vascular involvement,Uncontrolled hypertension,Active liver disease,Known or suspected pregnancy,Breast cancer or other estrogen-sensitive neoplasia,Heavy smoking (≥15 cigarettes/day) and age ≥35
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 significant food interactions. Grapefruit juice may slightly increase estrogen levels but not clinically relevant. A high-fat meal may delay absorption but does not reduce efficacy. Avoid excessive alcohol as it may increase liver enzymes and theoretically reduce efficacy.
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.
FDA Pregnancy Category X. Combined hormonal contraceptives (CHCs) are contraindicated in pregnancy. First trimester exposure is associated with a low risk of fetal malformations; however, CHCs should be discontinued if pregnancy occurs. Second and third trimester exposure may increase risks of fetal adverse outcomes, including but not limited to congenital anomalies and fetal demise. Use is not recommended at any trimester.
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).
CHCs may reduce milk production and composition. Small amounts of synthetic estrogen and progestin are excreted in breast milk. M/P ratio not specifically reported for this combination; ethinyl estradiol M/P ratio approximately 0.02-0.05. Use during lactation is generally not recommended, especially in early postpartum period. Alternative contraception should be considered.
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.
Contraindicated in pregnancy; no dose adjustments applicable as drug should be discontinued immediately upon confirmed pregnancy. Pharmacokinetic changes during pregnancy (e.g., increased clearance) are not relevant given contraindication.
Contraindicated in pregnancy; no dose adjustments applicable. Discontinue medication immediately upon pregnancy detection.
HAILEY 1.5/30 is a combination oral contraceptive containing ethinyl estradiol 30 mcg and levonorgestrel 1.5 mg. It is a monophasic pill with 21 active tablets. Counsel patients that missed pills increase pregnancy risk, especially if more than one active pill is missed. Use back-up contraception for 7 days if a dose is missed. Consider increased risk of venous thromboembolism (VTE) in smokers over 35, obese patients, or those with thrombophilia. Nausea may be reduced by taking with food or at bedtime. Spotting is common in first 3 cycles; if persistent, rule out pregnancy or other causes.
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 pill daily at the same time for 21 days, then 7 placebo pills.,If you miss a pill, follow the package insert instructions for missed doses and use back-up contraception (e.g., condoms) for 7 days.,Do not smoke while taking this medication, especially if over age 35, due to increased risk of blood clots.,Common side effects include nausea, breast tenderness, and spotting, which usually improve after 3 cycles.,Seek immediate medical attention for symptoms of blood clots: sudden leg pain/swelling, chest pain, shortness of breath, or severe headache.,Antibiotics (except rifampin) do not reduce effectiveness; however, certain drugs like rifampin, griseofulvin, and some anticonvulsants may decrease efficacy.,Store at room temperature, away from moisture and heat.
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 HAILEY 1.5/30 vs ALYACEN 1/35, answered by our medical review team.
HAILEY 1.5/30 is a Oral Contraceptive that works by Combination oral contraceptive containing ethinyl estradiol and desogestrel. Ethinyl estradiol suppresses gonadotropin release via negative feedback on the hypothalamic-pituitary axis; desogestrel, a progestin, inhibits ovulation and alters cervical mucus and endometrial receptivity.. 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 HAILEY 1.5/30 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 HAILEY 1.5/30 is: One tablet (ethinyl estradiol 0.03 mg, levonorgestrel 0.15 mg) orally once daily at the same time each day for 21 days, followed by 7 placebo tablets. For continuous cycling, may take active tablets daily without placebo.. 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 HAILEY 1.5/30 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. HAILEY 1.5/30 is classified as Category C. FDA Pregnancy Category X. Combined hormonal contraceptives (CHCs) are contraindicated in pregnancy. First trimester exposure is associated with a low risk of fetal malformations; h. 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.