Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
OVIDREL vs DANAZOL
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
OVIDREL (choriogonadotropin alfa) acts as a luteinizing hormone (LH) agonist, binding to the LH/choriogonadotropin receptor on ovarian theca and granulosa cells, triggering ovulation and luteinization by inducing resumption of oocyte meiosis and follicle rupture.
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 final follicular maturation and early luteinization in infertile women undergoing controlled ovarian hyperstimulation (COH) for assisted reproductive technologies (ART),Induction of ovulation in anovulatory or oligo-ovulatory women who have been pretreated with follicle-stimulating hormone (FSH)
FDA: Treatment of endometriosis, fibrocystic breast disease, hereditary angioedema,Off-label: Idiopathic thrombocytopenic purpura, precocious puberty, gynecomastia
250 mcg subcutaneously once daily for 7 days following recombinant FSH stimulation. Alternatively, a single 250 mcg subcutaneous dose is used to trigger final follicular maturation 24-48 hours after last gonadotropin dose.
300-600 mg orally twice daily; maximum 800 mg/day
The terminal elimination half-life is approximately 30 hours (range 20-48 hours) in healthy adults. This supports a single-dose regimen for final follicular maturation in assisted reproductive technology.
Terminal elimination half-life is 4-4.5 hours; clinical context: requires multiple daily dosing to maintain therapeutic levels.
Primarily metabolized in the kidney and other tissues via proteolytic degradation into amino acids and peptides; not significantly metabolized by cytochrome P450 enzymes.
Primarily hepatic: undergoes oxidation and conjugation via CYP3A4, with metabolites excreted in urine and feces.
Primarily renal, with approximately 10% of the administered dose excreted unchanged in urine within 24 hours. The remainder undergoes metabolic degradation in the kidneys and liver.
Primarily hepatic metabolism; approximately 60% excreted in feces, 30% in urine as metabolites.
Highly bound to plasma proteins, predominantly albumin, with approximately 80-85% bound.
Highly protein bound: 97-99%, primarily to albumin.
Approximately 6 L (0.1 L/kg in a 60 kg adult), indicating limited distribution primarily to the extracellular space.
Approximately 1.5 L/kg; indicates extensive distribution into tissues, exceeding total body water.
Subcutaneous injection: approximately 80% absolute bioavailability. Not administered orally.
Oral bioavailability is approximately 100% due to extensive absorption, but first-pass metabolism reduces systemic availability to about 70-80%.
No specific dose adjustment guidelines; use caution in renal impairment. GFR <30 m L/min: consider alternatives due to potential accumulation.
No adjustment required for GFR ≥10 m L/min; avoid use in GFR <10 m L/min due to fluid retention risk
No specific dose adjustment guidelines; use caution in severe hepatic impairment (Child-Pugh C).
Child-Pugh A: no adjustment; Child-Pugh B: reduce dose by 50%; Child-Pugh C: contraindicated
Not indicated for pediatric use; no established pediatric dosing.
2-5 mg/kg/dose orally twice daily; maximum 400 mg/day
Not indicated for geriatric use; no standard dosing established.
Start at low end of adult dose, titrate cautiously due to increased risk of fluid retention and thromboembolism
None (no FDA black box warning for OVIDREL).
Danazol may cause thrombotic events, including pulmonary embolism and thrombophlebitis. It is contraindicated in patients with a history of thrombosis.
Ovarian hyperstimulation syndrome (OHSS): can be severe with pulmonary and vascular complications; monitor closely and discontinue if OHSS develops.,Ovarian torsion: risk is increased in patients with enlarged ovaries; evaluate for abdominal pain.,Respiratory distress syndrome: associated with severe OHSS.,Multiple pregnancy: increased risk; counsel patients on potential outcomes.,Congenital malformations: incidence may increase following gonadotropin therapy; no causal link established.,Thromboembolic events: increased risk, especially in patients with obesity, thrombophilia, or prior history.
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 choriogonadotropin alfa or any component of the formulation,Pituitary or hypothalamic tumors,Ovarian enlargement or cyst due to reasons other than polycystic ovary syndrome,Gynecological hemorrhage of unknown etiology,Ovarian, uterine, or breast carcinoma,Active thromboembolic disorders or prior history of the same,Primary ovarian failure,Uncontrolled thyroid or adrenal dysfunction
Pregnancy, lactation, porphyria, severe hepatic/renal/cardiac disease, undiagnosed abnormal genital bleeding, history of thromboembolic disorders, androgen-dependent tumors.
No known significant food interactions. Grapefruit may affect metabolism of certain hormones; avoid excessive grapefruit intake.
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.
OVIDREL (choriogonadotropin alfa) is not indicated for use during pregnancy. Based on its mechanism as a luteinizing hormone analog, inadvertent exposure during early pregnancy may theoretically support corpus luteum function, but no increased risk of congenital anomalies has been reported in postmarketing surveillance. First trimester: No known teratogenic risk, but limited data. Second trimester: Not applicable as not used. Third trimester: Not applicable.
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.
No data available on the excretion of choriogonadotropin alfa into human breast milk. The M/P ratio is unknown. Given its large molecular weight (~30-40 k Da), transfer into milk is likely low, but caution is recommended. Use during lactation only if clearly needed.
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.
OVIDREL is not indicated during pregnancy. No dose adjustment studies in pregnancy exist. If inadvertently administered during early pregnancy, the same dose (single SC injection of 250 mcg or 5000-10000 IU) is retained, but no therapeutic need. Pharmacokinetic changes due to pregnancy (e.g., increased volume of distribution) are not clinically relevant as the drug is a single-dose trigger.
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.
OVIDREL (choriogonadotropin alfa) is a recombinant human chorionic gonadotropin (h CG) used to trigger final follicular maturation and ovulation in assisted reproductive technology (ART). Administer subcutaneously exactly 36 hours before oocyte retrieval; timing is critical. Monitor for ovarian hyperstimulation syndrome (OHSS) risk, especially in patients with polycystic ovary syndrome (PCOS). Do not use in patients with primary ovarian failure or uncontrolled thyroid/adrenal dysfunction.
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.
Inject OVIDREL exactly as prescribed, at the same time each day if multiple doses are needed.,Common side effects include injection site reactions, headache, and nausea.,Contact your doctor immediately if you experience severe pelvic pain, nausea, vomiting, or weight gain (signs of OHSS).,OVIDREL may cause false positive pregnancy tests; consult your doctor if you get a positive result.
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 OVIDREL vs DANAZOL, answered by our medical review team.
OVIDREL is a Gonadotropin that works by OVIDREL (choriogonadotropin alfa) acts as a luteinizing hormone (LH) agonist, binding to the LH/choriogonadotropin receptor on ovarian theca and granulosa cells, triggering ovulation and luteinization by inducing resumption of oocyte meiosis and follicle rupture.. 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 OVIDREL 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 OVIDREL is: 250 mcg subcutaneously once daily for 7 days following recombinant FSH stimulation. Alternatively, a single 250 mcg subcutaneous dose is used to trigger final follicular maturation 24-48 hours after last gonadotropin dose.. 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 OVIDREL 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. OVIDREL is classified as Category C. OVIDREL (choriogonadotropin alfa) is not indicated for use during pregnancy. Based on its mechanism as a luteinizing hormone analog, inadvertent exposure during early pregnancy may. 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.