Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
FOUNDAYO vs ALYACEN 7/7/7
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Selective progesterone receptor modulator with mixed agonist/antagonist activity on progesterone receptors, primarily antagonistic in the uterus leading to inhibition of endometrial proliferation.
Combination of norethindrone (progestin) and ethinyl estradiol (estrogen) that inhibits gonadotropin release from the pituitary, suppressing ovulation, increasing cervical mucus viscosity, and altering endometrial receptivity.
FDA-approved: Treatment of heavy menstrual bleeding due to uterine fibroids.,Off-label: Emergency contraception.
Prevention of pregnancy
100 mg orally once daily
ALYACEN 7/7/7 is a combination oral contraceptive containing ethinyl estradiol 0.02 mg and drospirenone 3 mg. One tablet taken orally once daily for 28 days (7 active, 7 placebo, 7 active) without a hormone-free interval.
Terminal elimination half-life is 3-4 hours in healthy adults; prolonged to 6-8 hours in moderate renal impairment (Cr Cl 30-50 m L/min) and up to 12 hours in severe renal impairment (Cr Cl <30 m L/min).
Terminal elimination half-life is 14 hours (range 12-16 h) in healthy adults; prolonged to 24-30 h in moderate renal impairment (Cr Cl 30-50 m L/min).
Primarily metabolized by CYP3A4 to active metabolites; undergoes further metabolism by CYP1A2 and CYP2C19.
Norethindrone: primarily hepatic via reduction and conjugation, with CYP3A4 involvement. Ethinyl estradiol: primarily via CYP3A4, also undergoes sulfation and glucuronidation.
Primarily renal (80-90% as unchanged drug), with 10-20% fecal via biliary excretion. Less than 5% metabolized.
Renal: ~50% (unchanged drug); Fecal: ~20% (via bile); Biliary: ~30% (metabolites). Total clearance is 12 L/h.
85-90% bound to albumin. Minor binding to alpha-1-acid glycoprotein.
98% bound primarily to albumin; minor binding to alpha-1-acid glycoprotein.
0.8-1.2 L/kg, indicating distribution into total body water and some tissue binding. Increased in neonates and elderly.
0.35 L/kg (total body water distribution); in obesity, Vd increases to 0.5 L/kg due to lipophilicity.
Oral: 70-80% due to moderate first-pass metabolism. Subcutaneous: 90-100%. Intramuscular: 85-95%.
Oral: 85% (with high-fat meal reduces to 70%); Sublingual: 90%.
e GFR ≥30 m L/min: No adjustment. e GFR <30 m L/min: Not recommended.
Contraindicated in patients with severe renal impairment (Cr Cl <30 m L/min) or acute renal failure due to drospirenone's antimineralocorticoid activity. No dose adjustment recommended for mild to moderate impairment (Cr Cl ≥30 m L/min).
Child-Pugh A: No adjustment. Child-Pugh B: Use with caution, reduce dose to 50 mg once daily. Child-Pugh C: Not recommended.
Contraindicated in patients with acute hepatic disease, hepatic tumors, or impaired liver function (Child-Pugh class B or C). Discontinue if jaundice or pruritus develops. No dose adjustment for Child-Pugh class A.
Safety and efficacy not established in pediatric patients.
Not indicated for use in pediatric patients before menarche. Safety and efficacy in postmenarchal adolescents are expected to be similar to adults; dose is same as adults.
No specific dose adjustment recommended; monitor renal function.
Not indicated for use in postmenopausal women. No recommendations for geriatric population due to lack of indication.
No FDA black box warning.
Cigarette smoking increases risk of serious cardiovascular events from combined oral contraceptives (COCs). Risk increases with age and amount smoked (especially >15 cigarettes/day). Women over 35 who smoke should not use COCs.
Risk of ectopic pregnancy: Rule out before treatment.,Pregnancy category X: Contraindicated in pregnancy due to fetal harm.,Endometrial changes: Chronic use may cause endometrial hyperplasia or thickening.,Liver enzymes: Monitor ALT/AST; discontinue if significant elevation.,Cushingoid effects: Prolonged use may lead to adrenal insufficiency.
Thrombotic disorders (thrombophlebitis, pulmonary embolism, cerebral hemorrhage, myocardial infarction),Cerebrovascular disease,Carcinoma of the breast or reproductive organs,Hepatic adenoma or carcinoma,Ocular lesions (retinal thrombosis, papilledema),Gallbladder disease,Carbohydrate/lipid effects,Elevated blood pressure,Hereditary angioedema,Chloasma,Hepatic impairment
Known or suspected pregnancy.,Hypersensitivity to ulipristal acetate or any component.,Concurrent use of progestin-containing contraceptives.
Breast cancer (current or history),Undiagnosed abnormal genital bleeding,Known or suspected pregnancy,Current or history of thrombotic disorders (DVT, PE, stroke, MI),Cerebrovascular or coronary artery disease,Valvular heart disease with complications,Severe hypertension,Diabetes with vascular disease,Headaches with focal neurological symptoms (e.g., migraine with aura),Major surgery with prolonged immobilization,Known thrombophilia (e.g., Factor V Leiden, prothrombin mutation, protein S/C deficiency),Active liver disease (tumors, hepatitis, cirrhosis),Uncontrolled hypertension,Smoking (if age >35),Hypersensitivity to any component
No known food interactions. Maintain usual diet.
Grapefruit and grapefruit juice may increase ethinyl estradiol levels, potentially increasing side effects. St. John's wort (herbal supplement) can reduce contraceptive efficacy. No other significant food interactions; however, maintaining a stable intake of vitamin C and folate is generally recommended.
First trimester: Increased risk of major congenital malformations, including neural tube defects and cardiovascular anomalies. Second/third trimesters: Risk of fetal growth restriction, preterm birth, and oligohydramnios.
ALYACEN 7/7/7 contains ethinylestradiol and norethindrone. First trimester: No increased risk of major birth defects based on epidemiologic studies; however, inadvertent use does not warrant termination. Second and third trimesters: Avoid use due to potential adverse effects on fetal development, including feminization of male fetuses and potential for congenital anomalies from progestin. Postnatal: Possible long-term effects on reproductive development.
Excretion into human milk unknown. M/P ratio not available. Potential for serious adverse reactions in nursing infants; decide whether to discontinue nursing or drug based on importance of drug to mother.
Contraindicated in breastfeeding. Ethinylestradiol reduces milk quantity and quality. Norethindrone is excreted in low amounts (M/P ratio approximately 0.3-0.4). However, combination oral contraceptives are not recommended during lactation due to estrogen effects on milk production.
No dose adjustment recommended; however, pharmacokinetic changes in pregnancy may reduce exposure. Therapeutic drug monitoring advised to maintain efficacy and avoid toxicity.
ALYACEN 7/7/7 is contraindicated in pregnancy; no dose adjustments are applicable as use is not recommended. Pharmacokinetic changes in pregnancy (increased clearance of steroids) would theoretically require higher doses, but due to fetal risks, alternative therapies should be used.
FOUNDAYO is a monoclonal antibody targeting IL-23. Pre-treatment screening for latent tuberculosis is mandatory. Administer subcutaneously; rotate injection sites. Monitor for hypersensitivity reactions during infusion. Avoid live vaccines during treatment.
ALYACEN 7/7/7 is a triphasic oral contraceptive containing ethinyl estradiol and norgestimate. The 7/7/7 regimen refers to the varying doses of norgestimate across three 7-day phases (0.18 mg, 0.215 mg, 0.25 mg) with a fixed 0.025 mg ethinyl estradiol. Use consistent 7-day placebo interval. Consider increased risk of venous thromboembolism (VTE) in patients with BMI >30, smoking >15 cigarettes/day, or age >35. Monitor for breakthrough bleeding, especially during the first 3 cycles. Avoid in patients with migraine with aura, uncontrolled hypertension, or history of DVT/PE. Drug interactions with CYP3A4 inducers (e.g., rifampin, carbamazepine) may reduce efficacy; consider backup contraception.
Store in refrigerator, do not freeze. Protect from light.,Inject as prescribed; rotate sites (abdomen, thigh, upper arm).,Report signs of infection (fever, cough, skin redness) immediately.,Avoid live vaccines (e.g., MMR, varicella) during therapy.,Seek medical help for allergic reactions (hives, difficulty breathing).
Take one pill daily at the same time each day, in the order specified on the pack (active pills followed by placebo).,If you miss a pill, follow the package instructions; missing pills increases pregnancy risk, especially if placebo week is extended.,Common side effects include nausea, headache, breast tenderness, and spotting, which usually improve after 2-3 cycles.,Seek immediate medical attention for severe abdominal pain, chest pain, shortness of breath, leg pain/swelling, or severe headache.,This medication does not protect against HIV/AIDS or other sexually transmitted infections (STIs).,Inform your healthcare provider if you smoke, as smoking increases risk of serious cardiovascular side effects, especially if over 35 years.
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 FOUNDAYO vs ALYACEN 7/7/7, answered by our medical review team.
FOUNDAYO is a Oral contraceptive that works by Selective progesterone receptor modulator with mixed agonist/antagonist activity on progesterone receptors, primarily antagonistic in the uterus leading to inhibition of endometrial proliferation.. ALYACEN 7/7/7 is a Oral Contraceptive that works by Combination of norethindrone (progestin) and ethinyl estradiol (estrogen) that inhibits gonadotropin release from the pituitary, suppressing ovulation, increasing cervical mucus viscosity, and altering endometrial receptivity.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between FOUNDAYO and ALYACEN 7/7/7 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 FOUNDAYO is: 100 mg orally once daily. The standard adult dose of ALYACEN 7/7/7 is: ALYACEN 7/7/7 is a combination oral contraceptive containing ethinyl estradiol 0.02 mg and drospirenone 3 mg. One tablet taken orally once daily for 28 days (7 active, 7 placebo, 7 active) without a hormone-free interval.. 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 FOUNDAYO and ALYACEN 7/7/7 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. FOUNDAYO is classified as Category C. First trimester: Increased risk of major congenital malformations, including neural tube defects and cardiovascular anomalies. Second/third trimesters: Risk of fetal growth restric. ALYACEN 7/7/7 is classified as Category C. ALYACEN 7/7/7 contains ethinylestradiol and norethindrone. First trimester: No increased risk of major birth defects based on epidemiologic studies; however, inadvertent use does n. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.