Danazol is a synthetic androgen derived from ethisterone, primarily indicated for the treatment of endometriosis, fibrocystic breast disease, hereditary angioedema, and other hormone-responsive conditions. It functions by suppressing the pituitary-ovarian axis, leading to reduced secretion of gonadotropins and creating a pseudo-menopausal state. This mechanism helps alleviate symptoms such as pelvic pain, breast tenderness, and episodic swelling, offering targeted relief where conventional therapies may fall short. Its well-established efficacy and decades of clinical use make it a cornerstone in managing these complex disorders.

Features

• Synthetic steroid with attenuated androgenic, anabolic, and anti-estrogenic properties
• Oral administration with high bioavailability when taken with food
• Half-life of approximately 4–5 hours, metabolized extensively in the liver
• Available in 50 mg, 100 mg, and 200 mg capsules
• Requires prescription and regular monitoring during therapy

Benefits

• Reduces endometriosis-associated pelvic pain and lesion size
• Decreases frequency and severity of hereditary angioedema attacks
• Alleviates pain and nodularity in fibrocystic breast disease
• Provides an alternative to surgical intervention in select cases
• May help manage menorrhagia and premenstrual syndrome symptoms
• Supports fertility preservation in endometriosis by controlling disease progression

Common use

Danazol is commonly prescribed for the treatment of endometriosis, particularly in cases where pain is significant and other hormonal treatments are ineffective or contraindicated. It is also used for managing fibrocystic breast disease when symptoms are severe and conservative measures fail. In hereditary angioedema, danazol is employed prophylactically to prevent attacks. Off-label uses may include idiopathic thrombocytopenic purpura and gynecomastia, though evidence supporting these applications is less robust.

Dosage and direction

Dosage must be individualized based on condition, severity, and patient response. For endometriosis, typical starting doses range from 400–800 mg daily, divided into two doses. For fibrocystic breast disease, doses of 100–400 mg daily are common. In hereditary angioedema, initial doses may start at 200 mg two to three times daily, adjusted downward for maintenance. Always take with food to improve absorption. Regular liver function and lipid profile monitoring are advised. Treatment duration varies; for endometriosis, therapy is often limited to 6–9 months to minimize androgenic effects.

Precautions

Patients should be monitored for signs of virilization, such as voice deepening, clitoromegaly, or hirsutism, which may be irreversible. Liver function tests, lipid profiles, and complete blood counts should be performed periodically. Use with caution in patients with cardiac, renal, or hepatic impairment. Danazol may cause fluid retention; caution is advised in those with epilepsy, migraine, or cardiac dysfunction. It is not recommended during pregnancy or breastfeeding. Patients should use non-hormonal contraception due to potential teratogenicity.

Contraindications

Danazol is contraindicated in patients with known hypersensitivity to the drug or any of its components. It must not be used during pregnancy or in those with undiagnosed abnormal genital bleeding. Contraindications also include severe hepatic, renal, or cardiac dysfunction, and a history of thromboembolic disorders. It is not suitable for patients with porphyria or those with androgen-dependent tumors such as prostate or breast cancer.

Possible side effect

Common side effects include weight gain, acne, oily skin, edema, flushing, and reduced breast size. Androgenic effects like hirsutism, voice changes, and clitoral enlargement may occur and can be irreversible. Less frequently, hepatic dysfunction, anxiety, depression, and musculoskeletal cramps have been reported. Hematologic changes such as leukopenia or thrombocytopenia are possible. Some patients may experience hot flashes, sweating, or vaginitis.

Drug interaction

Danazol may potentiate the effects of warfarin, requiring close monitoring of INR. It can increase levels of cyclosporine, carbamazepine, and tacrolimus, necessitating dosage adjustments. Concurrent use with insulin or oral hypoglycemics may alter glycemic control. Danazol may reduce the efficacy of hormone-based contraceptives. Concomitant use with other hepatotoxic drugs should be avoided. Always inform the prescriber of all medications, including over-the-counter and herbal products.

Missed dose

If a dose is missed, take it as soon as remembered unless it is almost time for the next dose. Do not double the dose to catch up. Maintaining a consistent dosing schedule is important for therapeutic efficacy, especially in conditions like hereditary angioedema where prophylaxis is critical. Use a pill organizer or alarm reminders if forgetfulness is a recurring issue.

Overdose

Symptoms of overdose may include exaggerated androgenic effects, nausea, vomiting, and dizziness. There is no specific antidote; treatment is supportive and symptomatic. Gastric lavage or activated charcoal may be considered if ingestion was recent. Monitor vital signs, electrolyte balance, and hepatic function. Contact a poison control center or seek emergency medical attention immediately.

Storage

Store at room temperature (15–30°C) in a tightly closed container, away from light, moisture, and heat. Keep out of reach of children and pets. Do not use beyond the expiration date printed on the packaging. Avoid storing in bathrooms or damp areas to prevent degradation.

Disclaimer

This information is for educational purposes and does not replace professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider for personalized recommendations. Dosage, indications, and precautions may vary based on individual health status and regional prescribing guidelines. The author and publisher are not liable for any adverse effects resulting from the use or misuse of this information.

Reviews

Clinical studies and patient reports generally affirm danazol’s efficacy in reducing endometriosis pain and preventing hereditary angioedema attacks. However, its androgenic side effects are a significant drawback for many patients, leading to discontinuation in some cases. Healthcare providers often reserve it for short-term use or when other treatments fail. Overall, it remains a valuable option within a tailored therapeutic strategy.