Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
GILDESS FE 1.5/30 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 oral contraceptive: ethinyl estradiol (estrogen) and levonorgestrel (progestin) suppress gonadotropin secretion (FSH and LH) via negative feedback, inhibiting ovulation, increasing cervical mucus viscosity, and altering endometrial receptivity.
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
Prevention of pregnancy (FDA-approved)
One tablet orally once daily at the same time each day for 21 consecutive days, followed by 7 days of placebo tablets.
One tablet (0.1 mg levonorgestrel, 0.02 mg ethinyl estradiol) orally once daily for 21 days, followed by 7 days of placebo.
Ethinyl estradiol: terminal elimination half-life approximately 13-27 hours (mean ~17 hours); clinical context: supports daily dosing with steady state achieved in ~1 week. Gestodene: terminal elimination half-life approximately 12-15 hours; clinical context: allows for maintaining stable serum concentrations with once-daily dosing.
Terminal elimination half-life: 12–15 hours. Steady-state achieved within 5 days with Q12H dosing.
Ethinyl estradiol: primarily metabolized by CYP3A4; undergoes conjugation (glucuronidation and sulfation). Levonorgestrel: metabolized by reduction and conjugation; CYP3A4 involved.
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.
Ethinyl estradiol (EE) is primarily excreted in urine (40-45%) and feces (40-45%) as glucuronide and sulfate conjugates; less than 8% is excreted unchanged. Gestodene is extensively metabolized; its metabolites are excreted in urine (50-60%) and feces (30-40%), with less than 1% unchanged.
Renal: 50% as unchanged drug and metabolites; fecal: 40% as metabolites; biliary: ~10% as glucuronide conjugates.
Ethinyl estradiol: 97-98% bound to albumin; gestodene: 65-75% bound to sex hormone-binding globulin (SHBG) and 25-35% bound to albumin; total binding ~99%.
~99% bound to serum albumin and sex hormone-binding globulin.
Ethinyl estradiol: apparent Vd ~2.5-4.0 L/kg (mean ~3 L/kg); indicates extensive tissue distribution beyond plasma volume. Gestodene: apparent Vd ~0.7-1.0 L/kg; suggests moderate distribution to tissues.
2.8 L/kg (apparent Vd), indicating extensive tissue distribution.
Ethinyl estradiol: oral bioavailability approximately 40-45% due to first-pass metabolism (sulfation and glucuronidation in gut wall and liver); interindividual variability significant. Gestodene: oral bioavailability nearly 100% (99-100%) due to minimal first-pass metabolism; high and consistent absorption.
Oral: ~70% due to first-pass metabolism.
No dose adjustment required for mild to moderate renal impairment. Contraindicated in severe renal impairment (e GFR <30 m L/min/1.73 m²) due to potential estrogen-related fluid retention and hypertension.
No dose adjustment required for mild to moderate renal impairment. Not recommended for use in end-stage renal disease.
Contraindicated in Child-Pugh class B and C (moderate to severe hepatic impairment). Use with caution in Child-Pugh class A; closely monitor liver function.
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. Post-menarche: same as adult dosing; 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 in postmenopausal women due to lack of efficacy for contraception and potential increased thromboembolic risk.
Not indicated for use in postmenopausal women; no specific dose adjustment required in healthy elderly, but limited data available.
Cigarette smoking increases risk of serious cardiovascular events from combination oral contraceptive use. Risk increases with age (especially >35 years) and number of cigarettes smoked. Women >35 years who smoke should not use this product.
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 disorders (venous thromboembolism, arterial thromboembolism, stroke, myocardial infarction),Carcinoma of the breast and reproductive organs,Hepatic neoplasia,Gallbladder disease,Carbohydrate and lipid metabolism effects,Elevated blood pressure,Headache,Bleeding irregularities,Ocular lesions (e.g., retinal thrombosis),Depression
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,Cerebrovascular or coronary artery disease,Known or suspected breast cancer,Estrogen-dependent neoplasia,Undiagnosed abnormal genital bleeding,Pregnancy,Benign or malignant liver tumor,Hepatic impairment,Hypersensitivity to components,Women >35 years who smoke
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 significant food interactions. Grapefruit juice may slightly increase ethinyl estradiol levels but not clinically relevant. The iron component may cause gastrointestinal discomfort; taking with food can reduce this, but avoid taking with dairy (calcium) or caffeine as they may reduce iron absorption. Iron tablets should be taken with water or vitamin C source to enhance absorption, but not with tea, coffee, or milk.
Grapefruit juice may increase ethinyl estradiol levels; avoid large quantities. No significant food restrictions. Administer with food if GI upset occurs.
Pregnancy category X. Use contraindicated in pregnancy due to estrogenic effects on fetal development. First trimester: increased risk of congenital anomalies (cardiovascular, limb defects). Second and third trimesters: potential for fetal harm, including jaundice and liver dysfunction.
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 in breastfeeding. Estrogen and progestin components reduce milk production and quality. Limited data; M/P ratio not established. 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.
No dose adjustment due to contraindication in pregnancy. Pharmacokinetic changes in pregnancy (increased clearance) are not applicable as drug is not used.
Contraindicated in pregnancy; no dose adjustment recommended. If exposure occurs, immediate discontinuation is required. No pharmacokinetic data support safe use; avoid use entirely.
GILDESS FE 1.5/30 is a combination oral contraceptive containing ethinyl estradiol 30 mcg and gestodene 1.5 mg. Gestodene is a third-generation progestin with high progestational activity and minimal androgenic effects. The iron component (ferrous fumarate) is included to counteract menstrual blood loss. This formulation is associated with a lower risk of venous thromboembolism compared to second-generation pills but still carries a risk, particularly in smokers over 35. It should be taken at the same time daily to maintain efficacy. Breakthrough bleeding is common in the first few cycles; if persistent, rule out other causes. The iron tablets are not for contraceptive use and should be taken daily during the placebo week.
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 daily at the same time, preferably after an evening meal to minimize nausea.,If you miss a dose, follow the package instructions: if missed by less than 12 hours, take it immediately; if more than 12 hours, take the last missed pill and use backup contraception for 7 days.,Use additional barrier contraception for the first 7 days of starting the pill, or if starting after day 5 of cycle, for the first cycle.,Smoking increases the risk of serious cardiovascular side effects, especially if you are over 35 years old. Do not smoke while taking this medication.,Seek immediate medical attention if you experience symptoms of a blood clot: sudden leg pain/swelling, chest pain, shortness of breath, or sudden severe headache.,The iron tablets are not for contraception; they help replace iron lost during menstruation.,Do not use this medication if you are pregnant, have a history of blood clots, certain migraines, liver disease, or hormone-sensitive cancer.,Antibiotics (except rifampin) generally do not affect efficacy, but always consult your doctor if you are prescribed any new medication.
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 GILDESS FE 1.5/30 vs AFIRMELLE, answered by our medical review team.
GILDESS FE 1.5/30 is a Oral Contraceptive that works by Combination oral contraceptive: ethinyl estradiol (estrogen) and levonorgestrel (progestin) suppress gonadotropin secretion (FSH and LH) via negative feedback, inhibiting ovulation, increasing cervical mucus viscosity, and altering endometrial receptivity.. 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 GILDESS FE 1.5/30 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 GILDESS 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 tablets.. 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 GILDESS FE 1.5/30 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. GILDESS FE 1.5/30 is classified as Category C. Pregnancy category X. Use contraindicated in pregnancy due to estrogenic effects on fetal development. First trimester: increased risk of congenital anomalies (cardiovascular, limb. 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.