Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
LOESTRIN FE 1.5/30 vs ESTARYLLA
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Suppresses gonadotropin (FSH and LH) release via estrogen and progestin feedback inhibition, preventing ovulation; increases cervical mucus viscosity and alters endometrial lining.
Estarylla is a combination oral contraceptive containing ethinyl estradiol and norgestimate. It suppresses gonadotropin release (FSH and LH) via estrogen and progestin, inhibiting ovulation. Additionally, it increases cervical mucus viscosity and alters endometrial receptivity, impeding sperm penetration and implantation.
Prevention of pregnancy,Treatment of heavy menstrual bleeding (off-label),Treatment of dysmenorrhea (off-label),Treatment of acne (off-label)
FDA-approved: Prevention of pregnancy in women who elect to use oral contraceptives as a method of contraception.,Off-label: Acne vulgaris (for norgestimate-containing pills), management of menstrual disorders (e.g., dysmenorrhea, abnormal uterine bleeding), hormone therapy for transgender women (non-standardized).,Note: Off-label uses are not FDA-approved for this specific formulation.
One tablet orally once daily at the same time each day for 21 consecutive days, followed by 7 days of placebo (ferrous fumarate) tablets, then restart.
One tablet (0.02 mg ethinyl estradiol and 0.15 mg desogestrel) orally once daily for 21 days, followed by 7 days of placebo. Hormone-free interval of 7 days.
Norethindrone: ~5-14 hours (terminal); Ethinyl estradiol: ~13-27 hours (terminal). Clinically, steady-state achieved within 5-7 days.
Terminal elimination half-life of ethinyl estradiol is approximately 13-16 hours; clinical context: steady-state achieved within 5-7 days
Metabolized in liver via CYP3A4 (norethindrone) and hydroxylation/conjugation (ethinyl estradiol).
Ethinyl estradiol is primarily metabolized by CYP3A4, with conjugation to glucuronides and sulfates. Norgestimate is rapidly metabolized to its active metabolite, norelgestromin, and further to levonorgestrel; involvement of CYP2C19 and CYP3A4 in norgestimate metabolism is noted.
Renal: ~50-60% (norethindrone metabolites); Fecal: ~20-30% (norethindrone); Ethinyl estradiol: primarily renal (~40-50%) and fecal (~20-50%) as glucuronide and sulfate conjugates.
Renal: ~55% as metabolites, ~27% unchanged; Fecal: ~45% as metabolites
Norethindrone: ~80-90% bound to SHBG and albumin; Ethinyl estradiol: ~95-98% bound primarily to albumin (with some to SHBG).
Ethinyl estradiol: 97-98% bound to albumin, with minor binding to sex hormone-binding globulin
Norethindrone: ~4 L/kg; Ethinyl estradiol: ~4-10 L/kg; indicates extensive tissue distribution.
Ethinyl estradiol: approximately 2.8 L/kg; indicates extensive tissue distribution
Oral: Norethindrone ~64%; Ethinyl estradiol ~38-48% (due to first-pass metabolism).
Oral: approximately 55% due to first-pass metabolism; consistent in healthy females
No dose adjustment required for renal impairment; however, use with caution in patients with impaired renal function due to potential fluid retention.
No dose adjustment required for mild to moderate renal impairment. Not recommended for use in severe renal impairment or end-stage renal disease due to lack of data.
Contraindicated in acute hepatic disease or liver tumors (benign or malignant). For Child-Pugh Class A, no dose adjustment; avoid use in Class B or C.
Contraindicated in Child-Pugh class B and C (moderate to severe hepatic impairment). Use with caution in Child-Pugh class A; dose adjustment not specifically defined, but alternative contraception recommended.
Not indicated for use before menarche. For postmenarchal adolescents, same dosing as adults: one tablet orally once daily.
Approved for use in postmenarchal adolescents: same dosing as adults (one tablet daily for 21 days, then 7 days placebo). No weight-based dosing required.
Not indicated for use in postmenopausal women. No specific geriatric dosing.
Not indicated in postmenopausal women. No specific geriatric dosing; contraindicated in women over 60 years due to increased thromboembolic risk.
Cigarette smoking increases risk of serious cardiovascular events from combination oral contraceptive use; risk increases with age and heavy smoking (≥15 cigarettes/day) and is significant in women over 35. Women who use combination oral contraceptives should be strongly advised not to smoke.
Cigarette smoking increases the risk of serious cardiovascular side effects from combination oral contraceptives. This risk increases with age (especially in women over 35 years of age) and with the number of cigarettes smoked. Women who use combination hormonal contraceptives should be strongly advised not to smoke.
Increased risk of thromboembolic events; cardiovascular disease; hypertension; gallbladder disease; hepatic neoplasia; elevated liver enzymes; possible increased risk of breast/cervical cancer; glucose intolerance; fluid retention; hereditary angioedema; chloasma; irregular bleeding; depression; contact lens intolerance; possible reduced efficacy with enzyme-inducing drugs.
Thrombotic disorders: Increased risk of venous thromboembolism (VTE) and arterial thromboembolism (e.g., MI, stroke). Discontinue if thrombotic event occurs.,Cardiovascular disease: Avoid in women with uncontrolled hypertension, diabetes with vascular involvement, or history of thromboembolic disease.,Cigarette smoking: Strongly advise cessation, especially in women over 35.,Liver disease: Discontinue if jaundice or cholestasis develops; contraindicated in acute viral hepatitis or severe cirrhosis.,Hormone-dependent malignancies: Increased risk of breast cancer (current use) and cervical cancer; avoid if known or suspected breast cancer.,Gallbladder disease: Increased risk of gallstones.,Carbohydrate and lipid metabolism: Monitor glucose and lipids in predisposed patients; may impair glucose tolerance and increase triglycerides.,Headache: Evaluate if new-onset or worsening migraine, especially with focal neurological symptoms.,Uterine bleeding: Rule out pregnancy if amenorrhea occurs; irregular bleeding may require evaluation.,Depression: Monitor for mood changes; discontinue if severe depression recurs.,Angioedema: Risk in women with hereditary angioedema.
Thrombophlebitis or thromboembolic disorders; history of deep vein thrombosis or pulmonary embolism; cerebrovascular or coronary artery disease; known or suspected breast carcinoma; carcinoma of endometrium or other estrogen-dependent neoplasia; undiagnosed abnormal genital bleeding; cholestatic jaundice of pregnancy or jaundice with prior oral contraceptive use; hepatic adenoma or carcinoma; known or suspected pregnancy; hypersensitivity to any component; current or history of migraine with aura (age ≥35); heavy smoking (≥15 cigarettes/day) in women ≥35 years; uncontrolled hypertension; diabetes with vascular involvement; major surgery with prolonged immobilization; known thrombophilic conditions.
Known or suspected pregnancy,Current or past venous thrombosis (e.g., deep vein thrombosis, pulmonary embolism),Current or past arterial thrombosis (e.g., myocardial infarction, stroke) or prodromal conditions (e.g., angina, transient ischemic attack),Known thrombophilic disorders (e.g., Factor V Leiden, prothrombin mutation, antithrombin deficiency),History of cerebrovascular or coronary artery disease,Uncontrolled hypertension (sustained >160/100 mm Hg),Diabetes mellitus with nephropathy, retinopathy, neuropathy, or other vascular disease,Headaches with focal neurological symptoms (e.g., migraine with aura) in women over 35,Current or past breast cancer, or other estrogen- or progestin-sensitive cancer,Active liver disease (e.g., acute viral hepatitis, severe cirrhosis) or benign/malignant liver tumors,Undiagnosed abnormal uterine bleeding,Hypersensitivity to any component of Estarylla,Use of highly active antiretroviral therapy (HAART) containing ritonavir or direct-acting antivirals for hepatitis C (e.g., ombitasvir/paritaprevir/ritonavir) due to potential for hepatotoxicity
No significant food interactions. Grapefruit juice may slightly increase ethinyl estradiol levels but not clinically relevant. Separate iron tablets from high-calcium foods or supplements (e.g., dairy) to enhance iron absorption, but this does not affect contraceptive efficacy.
There are no known significant food interactions. Grapefruit juice may increase estrogen levels but clinical significance is unclear; consider moderate intake.
FDA Pregnancy Category X. Use contraindicated in pregnancy. First trimester: increased risk of neural tube defects, cardiovascular anomalies, and limb reduction defects. Second and third trimesters: associated with fetal harm, including masculinization of female fetuses due to progestin component. No safe use during pregnancy.
Estarylla (ethinyl estradiol/levonorgestrel) is a combined oral contraceptive. Use during pregnancy is contraindicated. First trimester: No strong evidence of major malformations from inadvertent exposure, but increased risk of cardiovascular and limb defects in some studies. Second and third trimesters: Associated with fetal harm, including cardiovascular effects (e.g., congenital heart defects) and possible estrogenic effects, though data are limited. Postnatal effects: Potential long-term developmental effects unknown. Overall risk is low but not zero; avoid use in pregnancy.
Small amounts of ethinyl estradiol and norethindrone acetate excreted in breast milk; M/P ratio not reported. May reduce milk production and quality. Use only if clearly needed; lowest effective dose recommended. Caution in nursing mothers.
Estarylla is excreted in breast milk in small amounts (ethinyl estradiol: M/P ratio ~0.2; levonorgestrel: M/P ratio ~0.3-0.4). Combined hormonal contraceptives may reduce milk production and affect milk composition, especially in early postpartum. Use is generally not recommended until breastfeeding is well-established (at least 6 weeks postpartum). For later use, progestin-only methods are preferred. Monitor infant for jaundice and growth.
Contraindicated in pregnancy; no dosing adjustment applicable. Discontinue immediately if pregnancy occurs.
Estarylla is contraindicated in pregnancy. No dosing adjustments are recommended because it should not be used. Pregnancy alters pharmacokinetics of oral contraceptives (e.g., increased volume of distribution, altered hepatic metabolism), but no dose changes are indicated due to contraindication. If inadvertently taken, discontinue immediately.
Loestrin Fe 1.5/30 contains norethindrone acetate 1.5 mg and ethinyl estradiol 30 mcg plus ferrous fumarate (75 mg) as placebo pills. The iron supplement does not affect contraceptive efficacy. Be aware of increased risk of venous thromboembolism, especially in smokers over 35. Use with caution in patients with migraine with aura. Drug interactions with CYP3A4 inducers (e.g., rifampin, carbamazepine) may reduce efficacy. Breakthrough bleeding is common in first few cycles. Do not use in patients with hepatic impairment or known thrombophilia.
Estarylla is a combination oral contraceptive containing ethinyl estradiol and norgestimate. It is indicated for prevention of pregnancy. Monitor for thromboembolic events, especially in smokers over 35. Counsel on missed dose management: take as soon as remembered, use backup contraception if more than 24 hours late. May reduce menstrual cramps and acne. Not recommended in patients with history of estrogen-dependent neoplasia, liver disease, or uncontrolled hypertension.
Take one tablet daily at the same time each day, starting on the first day of menstrual bleeding.,The first 21 tablets are active hormones; the last 7 tablets are iron supplements that do not prevent pregnancy.,Missed dose: if you miss one active tablet, take it as soon as remembered; no backup needed. If you miss two, take two tablets and use backup contraception for 7 days.,Iron tablets may cause dark stools; this is harmless.,Report symptoms of blood clots: sudden leg pain, chest pain, shortness of breath, or severe headache.,Use additional contraception if starting within 5 days of stopping another hormonal contraceptive.,Avoid smoking while on this medication, especially if over 35.
Take one pill daily at the same time each day.,If you miss a pill, take it as soon as remembered; use backup contraception if more than 24 hours late.,Do not smoke while taking this medication, especially if over 35.,Report any signs of blood clots: leg pain, chest pain, shortness of breath, or sudden vision changes.,This medication does not protect against HIV or other STDs.
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 LOESTRIN FE 1.5/30 vs ESTARYLLA, answered by our medical review team.
LOESTRIN FE 1.5/30 is a Combined Oral Contraceptive that works by Suppresses gonadotropin (FSH and LH) release via estrogen and progestin feedback inhibition, preventing ovulation; increases cervical mucus viscosity and alters endometrial lining.. ESTARYLLA is a Combined Oral Contraceptive that works by Estarylla is a combination oral contraceptive containing ethinyl estradiol and norgestimate. It suppresses gonadotropin release (FSH and LH) via estrogen and progestin, inhibiting ovulation. Additionally, it increases cervical mucus viscosity and alters endometrial receptivity, impeding sperm penetration and implantation.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between LOESTRIN FE 1.5/30 and ESTARYLLA depend on the specific clinical indication. These are both Combined 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 LOESTRIN FE 1.5/30 is: One tablet orally once daily at the same time each day for 21 consecutive days, followed by 7 days of placebo (ferrous fumarate) tablets, then restart.. The standard adult dose of ESTARYLLA is: One tablet (0.02 mg ethinyl estradiol and 0.15 mg desogestrel) orally once daily for 21 days, followed by 7 days of placebo. Hormone-free interval of 7 days.. 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 LOESTRIN FE 1.5/30 and ESTARYLLA 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. LOESTRIN FE 1.5/30 is classified as Category C. FDA Pregnancy Category X. Use contraindicated in pregnancy. First trimester: increased risk of neural tube defects, cardiovascular anomalies, and limb reduction defects. Second and. ESTARYLLA is classified as Category C. Estarylla (ethinyl estradiol/levonorgestrel) is a combined oral contraceptive. Use during pregnancy is contraindicated. First trimester: No strong evidence of major malformations f. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.