Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
GILDESS 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 of estrogen (ethinyl estradiol) and progestin (desogestrel) that inhibits gonadotropin release, suppressing ovulation, increasing cervical mucus viscosity, and altering endometrial morphology.
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.
Oral contraception
Prevention of pregnancy (FDA-approved)
One tablet orally once daily at the same time each day.
One tablet (0.1 mg levonorgestrel, 0.02 mg ethinyl estradiol) orally once daily for 21 days, followed by 7 days of placebo.
Ethinylestradiol: terminal half-life 13-17 hours (mean 15 h). Desogestrel active metabolite 3-keto-desogestrel: terminal half-life 23-28 hours (mean 25 h). Clinical: steady-state achieved by cycle day 7-10; missed pill instructions based on half-life.
Terminal elimination half-life: 12–15 hours. Steady-state achieved within 5 days with Q12H dosing.
Ethinyl estradiol undergoes first-pass metabolism in gut wall and liver via CYP3A4; desogestrel is metabolized by CYP2C9 and CYP2C19 to active metabolite etonogestrel.
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 ethinylestradiol glucuronide and sulfate conjugates; ~40% as desogestrel metabolites (largely as 3-keto-desogestrel glucuronide). Fecal: ~30-35% of desogestrel metabolites; <5% for ethinylestradiol. Biliary: minor for both.
Renal: 50% as unchanged drug and metabolites; fecal: 40% as metabolites; biliary: ~10% as glucuronide conjugates.
Ethinylestradiol: ~97% bound to albumin (90%) and SHBG (minor). 3-Keto-desogestrel: ~95% bound: albumin (65%) and SHBG (30%).
~99% bound to serum albumin and sex hormone-binding globulin.
Ethinylestradiol: Vd ~2.5-3.0 L/kg; distributes extensively into body tissues (breast, liver). 3-Keto-desogestrel: Vd ~1.5-2.0 L/kg; moderate tissue binding.
2.8 L/kg (apparent Vd), indicating extensive tissue distribution.
Oral: ethinylestradiol ~40-50% (due to first-pass metabolism); desogestrel ~76% (≥60% converted to active 3-keto-desogestrel after first pass).
Oral: ~70% due to first-pass metabolism.
Contraindicated in patients with renal impairment (e GFR <60 m L/min/1.73 m2) due to increased risk of hyperkalemia and reduced efficacy.
No dose adjustment required for mild to moderate renal impairment. Not recommended for use in end-stage renal disease.
Contraindicated in patients with hepatic impairment (Child-Pugh class B or C) due to impaired hormone metabolism and potential for adverse effects.
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 in pediatric patients. Safety and efficacy have not been established in females under 18 years of age.
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. Efficacy in women over 40 years of age has not been fully established; consider alternative contraception due to increased cardiovascular 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 and smoking intensity (especially in women over 35).
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.
Increased risk of thromboembolic disorders (e.g., DVT, PE),Myocardial infarction and stroke risk,Hepatic neoplasia,Gallbladder disease,Hypertension,Carbohydrate/lipid effects,Ocular lesions,Dose-related risk of VTE from desogestrel-containing pills
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,History of DVT or PE,Cerebrovascular or coronary artery disease,Known or suspected breast carcinoma,Estrogen-dependent neoplasia,Undiagnosed abnormal genital bleeding,Pregnancy,Hepatic adenoma or carcinoma,Active liver disease with abnormal function
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 restrictions. Grapefruit juice does not significantly interact with ethinylestradiol or gestodene. St. John's Wort (Hypericum perforatum) reduces contraceptive efficacy by inducing CYP3A4 metabolism; avoid concurrent use. High-fat meals may increase ethinylestradiol absorption slightly but no dose adjustment needed.
Grapefruit juice may increase ethinyl estradiol levels; avoid large quantities. No significant food restrictions. Administer with food if GI upset occurs.
First trimester: Combination oral contraceptives are not associated with a major increase in risk of birth defects. Second and third trimesters: Prolonged use may be associated with fetal harm including cardiovascular and skeletal anomalies, though data are limited. Known pregnancy contraindicates use.
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.
Ethinyl estradiol and levonorgestrel are excreted in breast milk in small amounts. M/P ratio not established. Potential for adverse effects in nursing infant, including reduced milk production and jaundice. Use not recommended in breastfeeding women.
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.
Contraindicated in pregnancy. No dose adjustments applicable; use should be discontinued immediately if pregnancy occurs.
Contraindicated in pregnancy; no dose adjustment recommended. If exposure occurs, immediate discontinuation is required. No pharmacokinetic data support safe use; avoid use entirely.
GILDESS 1.5/30 is a combined oral contraceptive (COC) containing ethinylestradiol 30 µg and gestodene 75 µg. Gestodene is a third-generation progestin with high progestogenic activity and low androgenic effects, reducing acne and hirsutism. This formulation has a higher risk of venous thromboembolism (VTE) compared to second-generation COCs. Avoid in women with migraines with aura, hypertension (BP >160/100), or BMI >30 due to increased VTE risk. For missed pills: if one pill is missed, take it as soon as remembered and continue; if two or more pills are missed, take the last missed pill, use backup contraception for 7 days, and consider emergency contraception if unprotected intercourse occurred.
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 in the evening, to reduce nausea.,If you miss a pill, follow the instructions in the package leaflet; if you miss more than one pill, use additional contraception (e.g., condoms) for 7 days.,Smoking increases the risk of serious cardiovascular side effects; do not smoke while taking this medication, especially if you are over 35.,Tell your doctor if you experience severe headache, chest pain, leg pain or swelling, visual disturbances, or jaundice.,This medication does not protect against sexually transmitted infections; use condoms for additional protection.,Vomiting or severe diarrhea within 4 hours of taking the pill reduces efficacy; consider it as a missed pill and use backup contraception.
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 1.5/30 vs AFIRMELLE, answered by our medical review team.
GILDESS 1.5/30 is a Oral Contraceptive that works by Combination of estrogen (ethinyl estradiol) and progestin (desogestrel) that inhibits gonadotropin release, suppressing ovulation, increasing cervical mucus viscosity, and altering endometrial morphology.. 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 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 1.5/30 is: One tablet orally once daily at the same time each day.. 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 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 1.5/30 is classified as Category C. First trimester: Combination oral contraceptives are not associated with a major increase in risk of birth defects. Second and third trimesters: Prolonged use may be associated wit. 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.