Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
DANAZOL vs GANIRELIX ACETATE
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
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.
Gonadotropin-releasing hormone (Gn RH) antagonist competitively blocks Gn RH receptors on pituitary gonadotropes, reducing secretion of luteinizing hormone (LH) and follicle-stimulating hormone (FSH).
FDA: Treatment of endometriosis, fibrocystic breast disease, hereditary angioedema,Off-label: Idiopathic thrombocytopenic purpura, precocious puberty, gynecomastia
Inhibition of premature LH surges in women undergoing controlled ovarian hyperstimulation for assisted reproductive technology (ART),Off-label: Treatment of hormone-sensitive cancers (e.g., prostate cancer) when rapid suppression of gonadotropins is needed
300-600 mg orally twice daily; maximum 800 mg/day
250 mcg subcutaneously once daily starting on day 2 or 3 of menstrual cycle, continued until day of h CG administration.
Terminal elimination half-life is 4-4.5 hours; clinical context: requires multiple daily dosing to maintain therapeutic levels.
Terminal elimination half-life is approximately 16.2 hours (range 11-19 hours) in healthy females; clinically supports once-daily dosing.
Primarily hepatic: undergoes oxidation and conjugation via CYP3A4, with metabolites excreted in urine and feces.
Primarily hepatically metabolized via peptide hydrolysis; no major CYP450 involvement.
Primarily hepatic metabolism; approximately 60% excreted in feces, 30% in urine as metabolites.
Renal (approximately 75% as unchanged drug and metabolites) and fecal (approximately 22%).
Highly protein bound: 97-99%, primarily to albumin.
Approximately 90%, primarily to albumin and alpha-1-acid glycoprotein.
Approximately 1.5 L/kg; indicates extensive distribution into tissues, exceeding total body water.
Approximately 0.9 L/kg, indicating distribution primarily into extracellular fluid and some tissue binding.
Oral bioavailability is approximately 100% due to extensive absorption, but first-pass metabolism reduces systemic availability to about 70-80%.
Subcutaneous: Approximately 100% (range 91-100%) relative to intravenous injection.
No adjustment required for GFR ≥10 m L/min; avoid use in GFR <10 m L/min due to fluid retention risk
No dose adjustment required for mild to moderate renal impairment. No data for severe renal impairment (Cr Cl < 30 m L/min).
Child-Pugh A: no adjustment; Child-Pugh B: reduce dose by 50%; Child-Pugh C: contraindicated
No clinical data for hepatic impairment. Use with caution in moderate to severe hepatic impairment.
2-5 mg/kg/dose orally twice daily; maximum 400 mg/day
Not approved for use in pediatric patients.
Start at low end of adult dose, titrate cautiously due to increased risk of fluid retention and thromboembolism
Not approved for use in geriatric patients.
Danazol may cause thrombotic events, including pulmonary embolism and thrombophlebitis. It is contraindicated in patients with a history of thrombosis.
None
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 reactions (urticaria, angioedema) have been reported,Ovarian hyperstimulation syndrome (OHSS) may occur with ART,Congenital abnormalities cannot be excluded; pregnancy should be excluded before use
Pregnancy, lactation, porphyria, severe hepatic/renal/cardiac disease, undiagnosed abnormal genital bleeding, history of thromboembolic disorders, androgen-dependent tumors.
Hypersensitivity to ganirelix or any component,Known or suspected pregnancy,Lactation (not recommended due to potential neonatal effects)
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.
No significant food interactions. Grapefruit may theoretically affect metabolism but data are lacking; caution is advised.
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.
Category X: Contraindicated in pregnancy. Animal studies show embryolethality and teratogenicity. Risk of fetal loss (first trimester) and potential malformations (all trimesters) due to hormonal disruption.
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.
Unknown if excreted in human breast milk; M/P ratio not available. Risk of adverse effects in infant due to potential hormonal activity. Use caution; avoid if possible.
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.
No dose adjustments in pregnancy; contraindicated. If inadvertently used, discontinue immediately; no study on pharmacokinetic changes in pregnancy.
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.
Administer subcutaneously in the abdomen. Rotate injection sites to prevent lipodystrophy. Monitor for ovarian hyperstimulation syndrome (OHSS) especially in patients with polycystic ovary syndrome. Use caution in patients with renal impairment.
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.
Inject exactly as prescribed, typically once daily during the stimulation phase.,Do not skip doses; missed doses may reduce effectiveness.,Report severe pelvic pain, nausea, vomiting, or rapid weight gain immediately.,Store at room temperature (20-25°C) and protect from light.,Use within 30 days after first use.
"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."
No interactions on record
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about DANAZOL vs GANIRELIX ACETATE, answered by our medical review team.
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.. GANIRELIX ACETATE is a Gonadotropin-Releasing Hormone Antagonist that works by Gonadotropin-releasing hormone (Gn RH) antagonist competitively blocks Gn RH receptors on pituitary gonadotropes, reducing secretion of luteinizing hormone (LH) and follicle-stimulating hormone (FSH).. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between DANAZOL and GANIRELIX ACETATE 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 DANAZOL is: 300-600 mg orally twice daily; maximum 800 mg/day. The standard adult dose of GANIRELIX ACETATE is: 250 mcg subcutaneously once daily starting on day 2 or 3 of menstrual cycle, continued until day of h CG administration.. 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 DANAZOL and GANIRELIX ACETATE 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. 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. GANIRELIX ACETATE is classified as Category C. Category X: Contraindicated in pregnancy. Animal studies show embryolethality and teratogenicity. Risk of fetal loss (first trimester) and potential malformations (all trimesters) . Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.