Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
REPRONEX vs DANAZOL
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
REPRONEX (urofollitropin) is a purified preparation of follicle-stimulating hormone (FSH) that stimulates ovarian follicular growth in women who do not have primary ovarian failure. It acts by binding to FSH receptors on granulosa cells, increasing c AMP and promoting follicular development and estrogen synthesis.
Danazol is a synthetic androgen derived from ethisterone that suppresses pituitary-ovarian axis by inhibiting gonadotropin release, leading to decreased estrogen and progesterone levels. It also has weak androgenic and progestational activity.
Induction of ovulation in oligo-ovulatory or anovulatory women with functional hypothalamic-pituitary dysfunction (WHO Group II),Controlled ovarian hyperstimulation for assisted reproductive technologies (ART) such as in vitro fertilization (IVF)
FDA: Treatment of endometriosis, fibrocystic breast disease, hereditary angioedema,Off-label: Idiopathic thrombocytopenic purpura, precocious puberty, gynecomastia
Men: 1000-2500 IU subcutaneously 3 times weekly for 6-12 months. Women: 75-300 IU subcutaneously or intramuscularly daily for 7-12 days.
300-600 mg orally twice daily; maximum 800 mg/day
Terminal elimination half-life: 24-30 hours (menotropins); clinically, it supports daily dosing during ovarian stimulation
Terminal elimination half-life is 4-4.5 hours; clinical context: requires multiple daily dosing to maintain therapeutic levels.
REPRONEX is a glycoprotein hormone that is cleared primarily by the liver and kidneys. The metabolic pathways involve proteolytic degradation. The terminal half-life is approximately 4-12 hours after subcutaneous administration.
Primarily hepatic: undergoes oxidation and conjugation via CYP3A4, with metabolites excreted in urine and feces.
Renal (approximately 80% as parent drug and metabolites); biliary/fecal (<5%)
Primarily hepatic metabolism; approximately 60% excreted in feces, 30% in urine as metabolites.
Approximately 10%; mainly albumin
Highly protein bound: 97-99%, primarily to albumin.
0.2-0.5 L/kg; reflects distribution primarily in extracellular fluid
Approximately 1.5 L/kg; indicates extensive distribution into tissues, exceeding total body water.
SC/IM: nearly 100%
Oral bioavailability is approximately 100% due to extensive absorption, but first-pass metabolism reduces systemic availability to about 70-80%.
No dose adjustment required for mild to moderate renal impairment. Contraindicated in severe renal impairment (e GFR <30 m L/min/1.73 m²).
No adjustment required for GFR ≥10 m L/min; avoid use in GFR <10 m L/min due to fluid retention risk
Child-Pugh A: no adjustment. Child-Pugh B: reduce dose by 50%. Child-Pugh C: contraindicated.
Child-Pugh A: no adjustment; Child-Pugh B: reduce dose by 50%; Child-Pugh C: contraindicated
Not recommended for use in pediatric patients (safety and efficacy not established).
2-5 mg/kg/dose orally twice daily; maximum 400 mg/day
No specific dose adjustment; use with caution due to potential for decreased renal function and increased risk of thromboembolic events.
Start at low end of adult dose, titrate cautiously due to increased risk of fluid retention and thromboembolism
REPRONEX should only be used by physicians who are experienced in infertility treatment and capable of monitoring ovarian response. Ovarian hyperstimulation syndrome (OHSS) may occur, which can be severe and potentially fatal. Multiple births have been reported.
Danazol may cause thrombotic events, including pulmonary embolism and thrombophlebitis. It is contraindicated in patients with a history of thrombosis.
Risk of ovarian hyperstimulation syndrome (OHSS), which can be severe,Risk of multiple gestation,Thromboembolic events,Ovarian torsion,Pulmonary complications (e.g., atelectasis, adult respiratory distress syndrome)
Hepatotoxicity (monitor LFTs), pseudotumor cerebri (benign intracranial hypertension), androgenic effects (hirsutism, acne, voice deepening), lipid changes (decreased HDL, increased LDL), thromboembolic events, and premature closure of epiphyses in children.
High levels of FSH indicating primary ovarian failure,Uncontrolled thyroid or adrenal dysfunction,An organic intracranial lesion (e.g., pituitary tumor),Abnormal uterine bleeding of undetermined origin,Ovarian cyst or enlargement of unknown etiology,Pregnancy,Hypersensitivity to urofollitropin or any component
Pregnancy, lactation, porphyria, severe hepatic/renal/cardiac disease, undiagnosed abnormal genital bleeding, history of thromboembolic disorders, androgen-dependent tumors.
No specific food interactions documented. Maintain adequate hydration to reduce OHSS risk. Avoid excessive alcohol or caffeine as they may affect fertility.
Take with food or milk to minimize gastrointestinal irritation. Avoid grapefruit juice as it may alter drug metabolism. Limit alcohol consumption due to increased risk of hepatotoxicity.
REPRONEX (menotropins) is classified as FDA Pregnancy Category X. Studies have shown that menotropins can cause fetal harm when administered to a pregnant woman. There is no indication for use during pregnancy, as it is used for ovulation induction in infertility. If used inadvertently, there is a risk of multiple gestations and potential for congenital anomalies, but no specific teratogenic pattern has been established. Use is contraindicated in pregnant women.
Danazol is contraindicated in pregnancy. First trimester exposure is associated with virilization of female fetus including clitoromegaly, labioscrotal fusion, and urogenital sinus abnormalities. Risk in second and third trimesters is also significant due to androgenic effects; fetal growth restriction and preterm birth may occur. No safe gestational period exists.
It is unknown whether menotropins are excreted in human milk. Due to the potential for serious adverse reactions in nursing infants, a decision should be made whether to discontinue nursing or discontinue the drug, taking into account the importance of the drug to the mother. No M/P ratio is available.
Danazol is excreted in human milk; M/P ratio not determined. Potential for adverse effects in breastfed infant (e.g., androgenization). Use is contraindicated during breastfeeding due to risk of virilization and other hormonal effects.
REPRONEX is contraindicated in pregnancy and should not be used. No dosing adjustments are applicable as it is not indicated for use during pregnancy. Pharmacokinetic changes in pregnancy do not apply because the drug is not administered during pregnancy.
Danazol is contraindicated in pregnancy; no dose adjustment recommendations exist. If inadvertently used during pregnancy, discontinue immediately and monitor for fetal effects. Pharmacokinetic changes in pregnancy are not studied; dose modifications are not applicable due to contraindication.
REPRONEX (menotropins) is a gonadotropin preparation containing FSH and LH activity. Monitor estradiol levels and follicular growth via ultrasound to adjust dosing and minimize ovarian hyperstimulation syndrome (OHSS) risk. Avoid use in primary ovarian failure. Administer intramuscularly; rotate injection sites. Concomitant h CG is required for final follicular maturation and ovulation trigger.
Monitor liver function tests; androgenic effects (acne, hirsutism, voice deepening) may occur; use with caution in patients with cardiac or renal impairment; may potentiate warfarin; effective for hereditary angioedema prophylaxis; check pregnancy test before initiation due to teratogenicity.
Store REPRONEX in the refrigerator and protect from light.,Administer exactly as prescribed; do not change dose or schedule.,You may experience bloating, pelvic discomfort, or mood swings; report severe abdominal pain, nausea, or rapid weight gain (signs of OHSS) immediately.,Multiple pregnancy is possible; discuss risks with your doctor.,Use barrier contraception until instructed to attempt conception.,Do not drive or operate machinery if dizziness or visual disturbances occur.
Do not take if pregnant or planning pregnancy; use effective contraception.,Report symptoms of liver toxicity (jaundice, dark urine, abdominal pain) immediately.,Avoid alcohol as it may increase hepatotoxicity risk.,May cause weight gain, acne, or voice changes; report if bothersome.,Take with food to reduce GI upset.,Use sunscreen due to photosensitivity risk.,Do not discontinue abruptly; taper under medical supervision.
No interactions on record
"Formestane, an aromatase inhibitor, reduces estrogen synthesis, while danazol, a synthetic androgen, possesses weak androgenic and anabolic activity. Concomitant use may lead to additive fluid retention due to danazol's mineralocorticoid-like effects and formestane's potential to cause fluid retention through estrogen withdrawal. This can result in peripheral edema, hypertension, or exacerbation of heart failure in susceptible patients."
"Danazol, a synthetic androgen with weak androgenic activity, may reduce the therapeutic efficacy of vildagliptin, a dipeptidyl peptidase-4 (DPP-4) inhibitor used for glycemic control in type 2 diabetes. The proposed mechanism involves danazol-induced activation of cytochrome P450 enzymes (particularly CYP3A4) and potential upregulation of glucagon counter-regulatory pathways, leading to increased vildagliptin clearance and diminished inhibition of DPP-4. Clinically, this interaction may result in elevated postprandial glucose levels and reduced HbA1c reduction, compromising glycemic management."
"Danazol, an androgenic steroid, can induce hepatic microsomal enzymes, particularly CYP2C9, which accelerates the metabolism of glipizide, a sulfonylurea antidiabetic agent. This increased clearance reduces glipizide's plasma concentrations, diminishing its insulinotropic effect and potentially leading to hyperglycemia and loss of glycemic control in patients with type 2 diabetes mellitus."
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about REPRONEX vs DANAZOL, answered by our medical review team.
REPRONEX is a Gonadotropin that works by REPRONEX (urofollitropin) is a purified preparation of follicle-stimulating hormone (FSH) that stimulates ovarian follicular growth in women who do not have primary ovarian failure. It acts by binding to FSH receptors on granulosa cells, increasing c AMP and promoting follicular development and estrogen synthesis.. DANAZOL is a Androgen/Antigonadotropin that works by Danazol is a synthetic androgen derived from ethisterone that suppresses pituitary-ovarian axis by inhibiting gonadotropin release, leading to decreased estrogen and progesterone levels. It also has weak androgenic and progestational activity.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between REPRONEX and DANAZOL 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 REPRONEX is: Men: 1000-2500 IU subcutaneously 3 times weekly for 6-12 months. Women: 75-300 IU subcutaneously or intramuscularly daily for 7-12 days.. The standard adult dose of DANAZOL is: 300-600 mg orally twice daily; maximum 800 mg/day. 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 REPRONEX and DANAZOL 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. REPRONEX is classified as Category C. REPRONEX (menotropins) is classified as FDA Pregnancy Category X. Studies have shown that menotropins can cause fetal harm when administered to a pregnant woman. There is no indica. DANAZOL is classified as Category C. Danazol is contraindicated in pregnancy. First trimester exposure is associated with virilization of female fetus including clitoromegaly, labioscrotal fusion, and urogenital sinus. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.