Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
BRAVELLE vs DANAZOL
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Bravelle (urofollitropin) is a purified preparation of follicle-stimulating hormone (FSH) that stimulates ovarian follicular growth and maturation by binding to FSH receptors on granulosa cells, increasing c AMP production and promoting follicular development.
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.
Ovulation induction in anovulatory women with polycystic ovary syndrome (PCOS),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
For ovulation induction: 150 IU subcutaneously or intramuscularly once daily for 5 days, starting on day 3 or 5 of menstrual cycle. For controlled ovarian hyperstimulation: 150-225 IU subcutaneously or intramuscularly once daily for 5-7 days, then adjust based on response.
300-600 mg orally twice daily; maximum 800 mg/day
Terminal elimination half-life approximately 5-6 hours in healthy adults. Extended in renal impairment (up to 24 hours with Cr Cl <30 m L/min).
Terminal elimination half-life is 4-4.5 hours; clinical context: requires multiple daily dosing to maintain therapeutic levels.
Primarily metabolized in the liver via renal excretion; metabolic pathways not fully characterized.
Primarily hepatic: undergoes oxidation and conjugation via CYP3A4, with metabolites excreted in urine and feces.
Primarily renal: 95% of administered dose excreted unchanged in urine within 24 hours. Biliary/fecal: 5% eliminated via feces.
Primarily hepatic metabolism; approximately 60% excreted in feces, 30% in urine as metabolites.
Approximately 10-20% bound to plasma proteins (albumin and α-1 acid glycoprotein).
Highly protein bound: 97-99%, primarily to albumin.
Approximately 0.3-0.5 L/kg. Distributing primarily in extracellular fluid; does not extensively penetrate tissues.
Approximately 1.5 L/kg; indicates extensive distribution into tissues, exceeding total body water.
Subcutaneous: 90-95% bioavailable relative to intramuscular route. Oral: not clinically used due to enzymatic degradation.
Oral bioavailability is approximately 100% due to extensive absorption, but first-pass metabolism reduces systemic availability to about 70-80%.
No specific guidelines exist for GFR-based dose modifications; use with caution in severe renal impairment (Cr Cl <30 m L/min) and monitor for adverse effects.
No adjustment required for GFR ≥10 m L/min; avoid use in GFR <10 m L/min due to fluid retention risk
No specific guidelines exist for Child-Pugh based modifications; use with caution in severe hepatic impairment and monitor for adverse effects.
Child-Pugh A: no adjustment; Child-Pugh B: reduce dose by 50%; Child-Pugh C: contraindicated
Not indicated for use in pediatric patients; safety and efficacy not established.
2-5 mg/kg/dose orally twice daily; maximum 400 mg/day
Not indicated for use in geriatric patients; safety and efficacy not established.
Start at low end of adult dose, titrate cautiously due to increased risk of fluid retention and thromboembolism
Bravelle should only be used by physicians who are experienced in infertility treatment and can manage potential serious adverse events, including ovarian hyperstimulation syndrome (OHSS) and multiple gestations.
Danazol may cause thrombotic events, including pulmonary embolism and thrombophlebitis. It is contraindicated in patients with a history of thrombosis.
Ovarian enlargement and ovarian hyperstimulation syndrome (OHSS) – can lead to serious complications; discontinue treatment if OHSS is suspected.,Multiple gestations – increased risk of multiple births.,Ovarian torsion – report sudden abdominal pain.,Pulmonary and vascular complications – thromboembolic events; discontinue if suspected.,Ectopic pregnancy and spontaneous abortion – higher rates in ART patients.,Neoplasms – risk of ovarian neoplasms with repeated use.
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.
Hypersensitivity to urofollitropin or any component,High levels of FSH indicating primary ovarian failure,Uncontrolled thyroid or adrenal dysfunction,Known or suspected pregnancy,Ovarian cyst or enlargement of undetermined origin,Abnormal uterine bleeding of undetermined origin,Sex hormone-dependent tumors (e.g., breast, uterus, ovary)
Pregnancy, lactation, porphyria, severe hepatic/renal/cardiac disease, undiagnosed abnormal genital bleeding, history of thromboembolic disorders, androgen-dependent tumors.
No known food interactions. Maintain normal diet and hydration. Avoid alcohol as it may exacerbate side effects like nausea.
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.
Pregnancy Category X. Urofollitropin is contraindicated in pregnant women due to risk of fetal harm. First trimester: Ovarian hyperstimulation syndrome (OHSS) and multiple gestations. Second and third trimesters: No direct fetal effects reported, but risks associated with multiple gestation (preterm birth, low birth weight). Maternal OHSS may lead to thromboembolism.
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.
Urofollitropin is not indicated for use during lactation. No data on excretion in human milk, M/P ratio not established. Use during breastfeeding is contraindicated due to potential for adverse effects on infant hormone levels.
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.
No dose adjustment applicable as therapy is discontinued upon confirmed pregnancy. No pharmacokinetic data during pregnancy; drug is not used after conception due to contraindication.
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.
BRAVELLE (urofollitropin) is a purified FSH product used for controlled ovarian hyperstimulation. Administer subcutaneously; rotate injection sites. Monitor estradiol levels and follicle growth via ultrasound. Risk of ovarian hyperstimulation syndrome (OHSS); consider using Gn RH antagonist protocols to reduce risk. Do not administer if patient has high baseline FSH levels (>15 IU/L) indicating poor ovarian reserve.
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.
Teach proper injection technique and site rotation (abdomen, thigh).,Report immediately if severe pelvic pain, nausea, vomiting, or rapid weight gain occurs (OHSS signs).,Avoid intercourse until instructed to prevent multiple pregnancy.,Inform of multiple pregnancy risk (especially twins).,Store vials in refrigerator (2-8°C) and protect from light.
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 BRAVELLE vs DANAZOL, answered by our medical review team.
BRAVELLE is a Gonadotropin that works by Bravelle (urofollitropin) is a purified preparation of follicle-stimulating hormone (FSH) that stimulates ovarian follicular growth and maturation by binding to FSH receptors on granulosa cells, increasing c AMP production and promoting follicular development.. 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 BRAVELLE 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 BRAVELLE is: For ovulation induction: 150 IU subcutaneously or intramuscularly once daily for 5 days, starting on day 3 or 5 of menstrual cycle. For controlled ovarian hyperstimulation: 150-225 IU subcutaneously or intramuscularly once daily for 5-7 days, then adjust based on response.. 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 BRAVELLE 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. BRAVELLE is classified as Category C. Pregnancy Category X. Urofollitropin is contraindicated in pregnant women due to risk of fetal harm. First trimester: Ovarian hyperstimulation syndrome (OHSS) and multiple gestatio. 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.