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 ALTAVERA
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 of ethinyl estradiol and desogestrel: ethinyl estradiol suppresses gonadotropin release, inhibiting ovulation; desogestrel (progestin) causes cervical mucus thickening and endometrial atrophy, preventing implantation.
Oral contraception
Prevention of pregnancy,Treatment of moderate acne vulgaris (in females ≥15 years with no contraindications)
One tablet orally once daily at the same time each day.
1 tablet (ethinyl estradiol 0.03 mg / levonorgestrel 0.15 mg) orally once daily for 21 days, followed by 7 placebo days.
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.
Levonorgestrel: terminal elimination half-life 25±10 hours; ethinyl estradiol: 13±7 hours. Clinical context: steady-state concentrations achieved within 5-7 days; contraceptive efficacy requires consistent daily 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: primarily metabolized by CYP3A4; undergoes sulfation and glucuronidation. Desogestrel: rapidly converted to active metabolite etonogestrel via CYP2C9 and CYP2C19; further metabolism by CYP3A4.
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 excretion of metabolites and unchanged drug: ~30% (levonorgestrel) and ~20% (ethinyl estradiol) in urine; biliary/fecal elimination: ~40-50% as conjugates and metabolites.
Ethinylestradiol: ~97% bound to albumin (90%) and SHBG (minor). 3-Keto-desogestrel: ~95% bound: albumin (65%) and SHBG (30%).
Levonorgestrel: 98-99% bound to sex hormone-binding globulin (SHBG) and albumin; ethinyl estradiol: 98% bound to albumin.
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.
Levonorgestrel: Vd ~1.8 L/kg (suggesting extensive tissue distribution). Ethinyl estradiol: Vd ~2.4 L/kg.
Oral: ethinylestradiol ~40-50% (due to first-pass metabolism); desogestrel ~76% (≥60% converted to active 3-keto-desogestrel after first pass).
Oral bioavailability: levonorgestrel ~100% (nearly complete); ethinyl estradiol ~45-50% (first-pass hepatic 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. Contraindicated in severe renal disease or acute renal failure due to potential fluid retention.
Contraindicated in patients with hepatic impairment (Child-Pugh class B or C) due to impaired hormone metabolism and potential for adverse effects.
Contraindicated in severe hepatic dysfunction (Child-Pugh class B or C). Use caution in mild to moderate impairment (Child-Pugh A); monitor liver enzymes.
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. For postmenarchal adolescents, same dosing as adults (1 tablet daily, 21/7 regimen) after evaluation of risks.
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 postmenopausal women. No specific geriatric dosing; consider increased risk of thromboembolism, cardiovascular disease, and metabolic effects in older women of reproductive age.
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 combined oral contraceptives. Risk increases with age (especially >35 years) and with number of cigarettes smoked. Women who use combined 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: risk of venous thromboembolism (VTE), stroke, myocardial infarction; discontinue if thrombotic event occurs.,Hepatic disease: discontinue if jaundice or liver function abnormalities develop.,Hypertension: monitor blood pressure; discontinue if uncontrolled.,Carbohydrate metabolism: may affect glucose tolerance; monitor diabetic patients.,Depression: discontinue if significant depression occurs.,Gallbladder disease: increased risk of cholelithiasis.
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 carcinoma,Estrogen-dependent neoplasia (known or suspected),Undiagnosed abnormal genital bleeding,Cholestatic jaundice of pregnancy or jaundice with prior pill use,Hepatic adenoma or carcinoma (known or suspected),Pregnancy (known or suspected),Hypersensitivity to any component
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.
No significant food interactions. Alcohol does not affect efficacy but may increase risk of adverse effects such as nausea. Grapefruit juice has no known interaction. Avoid excessive alcohol consumption due to potential hepatotoxicity.
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.
ALTAVERA contains ethinyl estradiol and levonorgestrel. First trimester: Inadvertent exposure during organogenesis is associated with a very low absolute risk of cardiovascular defects (relative risk 1.2-1.4) and no consistent increase in other major malformations. Second and third trimesters: No known teratogenic effects, but theoretical risks from estrogenic effects (e.g., feminization of male fetus). Postnatal: No increased risk of long-term developmental effects from pregnancy exposure.
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.
Combined oral contraceptives may reduce milk production and quality, especially in early lactation. Ethinyl estradiol transfers into breast milk at low levels (M/P ratio approximately 0.1-0.2), excluding clinical effects in term infants. Levonorgestrel transfer is minimal (M/P ratio ~0.2-0.4). Use is generally avoided in breastfeeding women, especially during the first 6 weeks postpartum. Progestin-only methods are preferred.
Contraindicated in pregnancy. No dose adjustments applicable; use should be discontinued immediately if pregnancy occurs.
Contraindicated in pregnancy. No dose adjustment recommended because use is discontinued upon confirmed or suspected pregnancy. Pharmacokinetic changes in pregnancy (e.g., increased hepatic clearance, altered binding proteins) are not relevant for this indication.
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.
ALTAVERA is a combined oral contraceptive (COC) containing ethinylestradiol and levonorgestrel. It inhibits ovulation via suppression of gonadotropins. Counsel patients to take at the same time daily to maintain efficacy. Missed pill management: if missed within 12 hours, take immediately; if >12 hours, take last missed pill and use backup contraception for 7 days. Be aware of increased VTE risk, especially in smokers over 35. May reduce effectiveness of lamotrigine; monitor seizure control. Initiate on the first day of menses or first Sunday after onset.
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 tablet daily at the same time each day, with or without food.,If you miss a pill by less than 12 hours, take it as soon as you remember. If more than 12 hours, take the missed pill and use a backup method (e.g., condoms) for the next 7 days.,Smoking increases your 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 sudden severe headache, chest pain, leg pain/swelling, or vision changes (symptoms of blood clots).,This medication does not protect against HIV or other sexually transmitted infections.,If you are taking lamotrigine or other anticonvulsants, tell your doctor; your seizure medication may be less effective.,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 GILDESS 1.5/30 vs ALTAVERA, 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.. ALTAVERA is a Combined Oral Contraceptive that works by Combination of ethinyl estradiol and desogestrel: ethinyl estradiol suppresses gonadotropin release, inhibiting ovulation; desogestrel (progestin) causes cervical mucus thickening and endometrial atrophy, preventing implantation.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between GILDESS 1.5/30 and ALTAVERA 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 ALTAVERA is: 1 tablet (ethinyl estradiol 0.03 mg / levonorgestrel 0.15 mg) orally once daily for 21 days, followed by 7 placebo 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 GILDESS 1.5/30 and ALTAVERA 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. ALTAVERA is classified as Category C. ALTAVERA contains ethinyl estradiol and levonorgestrel. First trimester: Inadvertent exposure during organogenesis is associated with a very low absolute risk of cardiovascular def. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.