Last reviewed 2026-04-20 · How we verify

Danzol (DANAZOL)

At a glance

Approved indications

• Endometriosis
• Fibrocystic breast changes
• Hereditary Angioedema Prevention

Boxed warnings

• WARNINGS Use of danazol in pregnancy is contraindicated. A sensitive test (e.g., beta subunit test if available) capable of determining early pregnancy is recommended immediately prior to start of therapy. Additionally a non-hormonal method of contraception should be used during therapy. If a patient becomes pregnant while taking danazol, administration of the drug should be discontinued and the patient should be apprised of the potential risk to the fetus. Exposure to danazol in utero may result in androgenic effects on the female fetus; reports of clitoral hypertrophy, labial fusion, urogenital sinus defect, vaginal atresia, and ambiguous genitalia have been received (see PRECAUTIONS: Pregnancy, Teratogenic Effects ). Thromboembolism, thrombotic and thrombophlebitic events including sagittal sinus thrombosis and life-threatening or fatal strokes have been reported. Experience with long-term therapy with danazol is limited. Peliosis hepatis and benign hepatic adenoma have been observed with long-term use. Peliosis hepatis and hepatic adenoma may be silent until complicated by acute, potentially life-threatening intraabdominal hemorrhage. The physician therefore should be alert to this possibility. Attempts should be made to determine the lowest dose that will provide adequate protection. If the drug was begun at a time of exacerbation of hereditary angioneurotic edema due to trauma, stress or other cause, periodic attempts to decrease or withdraw therapy should be considered. Danazol has been associated with several cases of benign intracranial hypertension also known as pseudotumor cerebri. Early signs and symptoms of benign intracranial hypertension include papilledema, headache, nausea and vomiting, and visual disturbances. Patients with these symptoms should be screened for papilledema and, if present, the patients should be advised to discontinue danazol immediately and be referred to a neurologist for further diagnosis and care.

Common side effects

• Hepatic dysfunction
• Hepatic adenoma
• Peliosis hepatis
• Cholestatic jaundice
• Malignant liver tumors
• Hirsutism
• Edema
• Hair loss
• Voice change
• Hoarseness
• Sore throat
• Instability or deepening of pitch

Drug interactions

• dicoumarol
• phenprocoumon
• simvastatin
• tacrolimus
• warfarin

Key clinical trials

• A Phase 3 Study of Pacritinib in Patients With Primary Myelofibrosis, Post Polycythemia Vera Myelofibrosis, or Post-Essential Thrombocythemia Myelofibrosis (PHASE3)
• Low-Dose Danazol for the Treatment of Telomere Related Diseases (PHASE2)
• A Study Comparing Imetelstat Versus Best Available Therapy for the Treatment of Intermediate-2 or High-risk Myelofibrosis (MF) Who Have Not Responded to Janus Kinase (JAK)-Inhibitor Treatment (PHASE3)
• Letrozole vs Danazol for Endometriosis-Related Pain: Randomized Trial (PHASE2)
• The TELO-SCOPE Study: Attenuating Telomere Attrition With Danazol. Is There Scope to Dramatically Improve Health Outcomes for Adults and Children With Pulmonary Fibrosis (PHASE2)
• Danazol for Treatment of Cytopenias in Patients With Cirrhosis (PHASE2)
• Effectiveness of Early Intervention in Transfusion Independent Aplastic Anemia: a Retrospective Medical Claims Database Study
• Safety Study of Danazol With Plasma Exchange and Steroids for the Treatment of Thrombotic Thrombocytopenic Purpura (TTP) (PHASE2)

Primary sources

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Competitive intelligence

For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:

• Danzol CI brief — competitive landscape report
• Danzol updates RSS · CI watch RSS