Danazol
Pronunciation: DAN-a-zol.
- Generic name
- danazol
- Drug class
- Synthetic androgen derivative (attenuated androgen / pituitary gonadotropin inhibitor)
- Form
- Capsule, 50 mg, 100 mg, or 200 mg
- Route
- Oral
- Legal status
- Prescription-only
Availability and supply rules vary by country
Trade names by country: United States · United Kingdom · Canada · Australia · New Zealand
Australia: Danazol Capsules / AZOL 200 (all ARTG registrations cancelled 19 March 2021; no current TGA-registered product) (5) · Full directory
What danazol is and how it works
Danazol is a synthetic hormone-based medicine (a weak androgen) that suppresses ovarian hormone production. It is used to treat endometriosis, fibrocystic breast disease, and to prevent attacks of hereditary angioedema (a genetic condition causing recurrent episodes of swelling). (1) (2)
Take danazol exactly as your prescriber directs. It has serious potential effects on hormone levels and must not be used during pregnancy. Your prescriber will monitor you closely, including with blood tests, throughout treatment.
Mechanism of action: how danazol works
Danazol is a synthetic steroid (attenuated androgen) that suppresses the pituitary-ovarian axis and inhibits pituitary gonadotropin output, reducing oestrogen production and inducing an atrophic, inactive endometrium; it also has weak androgenic, anti-androgenic, progestogenic, anti-progestogenic, oestrogenic, and anti-oestrogenic activity. (1) (2)
What danazol is used for
Endometriosis
Used to treat symptoms of endometriosis (such as pelvic pain and painful periods) and to reduce the extent of endometriosis tissue, either alongside surgery or as sole hormone therapy in people who have not responded to other treatments. (1) (2)
Fibrocystic breast disease
Used for symptomatic relief of severe breast pain and tenderness from fibrocystic breast disease, in people who have not had adequate relief from other treatments. Breast cancer must be ruled out before starting treatment for this use. (2)
Hereditary angioedema (prevention)
Used to prevent attacks of hereditary angioedema (a genetic condition causing recurrent swelling of the skin, throat, airway, or abdomen). (1) (4)
Before taking danazol
Do not take / not appropriate for
- Do not take danazol if you are pregnant or could become pregnant without using a non-hormonal method of contraception. Danazol can cause serious, irreversible androgenic effects on a female fetus (such as ambiguous genitalia). (all countries) (1) (2)
- Do not take danazol if you are breastfeeding. (all countries) (1) (2)
- Do not take danazol if you have undiagnosed abnormal vaginal or genital bleeding, until the cause has been identified. (all countries) (1) (2)
- Do not take danazol if you have markedly impaired liver, kidney, or heart function. (all countries) (1) (2)
- Do not take danazol if you have porphyria, an androgen-dependent tumour, or active (or a history of) blood clots/thromboembolic disease. (all countries) (1) (2)
- Do not take danazol together with simvastatin -- this combination is contraindicated due to increased risk of muscle toxicity. (Canada) (2)
- Do not take danazol if you have had a hypersensitivity reaction to it or any of its ingredients. (all countries) (1)
Tell your clinician about
- Any history of epilepsy, migraine, heart or kidney problems, high blood pressure, or polycythaemia (too many red blood cells).
- Any history of blood clots, stroke, or clotting disorders.
- Any lipid (cholesterol) disorder -- danazol can alter lipid levels.
- All other medicines you take, especially warfarin or other anticoagulants, carbamazepine, phenytoin, phenobarbital, cyclosporin, tacrolimus, insulin or oral diabetes medicines, antihypertensive medicines, and statins.
- Pregnancy plans, current pregnancy, or breastfeeding.
How to take danazol
- Swallow capsules whole, as directed by your prescriber.
- For endometriosis, therapy is usually started during your menstrual period.
- Attend all follow-up appointments and blood tests -- these monitor your liver function and blood counts during treatment.
- Use a non-hormonal method of contraception throughout treatment if you are able to become pregnant.
Procedures and treatment changes
Tell the treating team before surgery, procedures, or any medicine change. Do not alter treatment without the responsible clinician. (1) (2) (3) (4) (5) (6)
Missed dose
If you miss a dose, take it as soon as you remember unless it is nearly time for your next dose -- do not take an extra dose. Contact your prescriber if you are unsure or miss multiple doses.
Overdose
Seek urgent medical attention if you think you or someone else has taken too much danazol. (1)
Side effects
Side effects and their urgency vary; report severe, persistent, or concerning symptoms.
Weight gain, acne, and oily skin (seborrhea).
What to notice: Weight gain, acne, and oily skin (seborrhea).
What to do: Discuss persistent or troublesome symptoms with the treating clinician or pharmacist. (1)
Menstrual disturbances, including lighter or absent periods.
What to notice: Menstrual disturbances, including lighter or absent periods.
What to do: Discuss persistent or troublesome symptoms with the treating clinician or pharmacist. (1)
Flushing, sweating, and vaginal dryness or irritation.
What to notice: Flushing, sweating, and vaginal dryness or irritation.
What to do: Discuss persistent or troublesome symptoms with the treating clinician or pharmacist. (1)
Nervousness or emotional changes.
What to notice: Nervousness or emotional changes.
What to do: Discuss persistent or troublesome symptoms with the treating clinician or pharmacist. (1)
Mild hirsutism (increased hair growth) or hair loss.
What to notice: Mild hirsutism (increased hair growth) or hair loss.
What to do: Discuss persistent or troublesome symptoms with the treating clinician or pharmacist. (1)
Serious warnings
Signs of virilization (masculinizing effects) — high caution
Symptoms: Deepening or hoarseness of the voice, increased hair growth (hirsutism), hair loss similar to male-pattern baldness, or enlargement of the clitoris.
Action: Tell your prescriber promptly if you notice any of these changes. Some of these effects, especially voice changes and clitoral enlargement, may not be reversible even after your prescriber has you ask the prescriber about stopping it -- early reporting matters. (1) (2)
Signs of liver problems, including rare liver tumours (peliosis hepatis, hepatic adenoma) — high caution
Symptoms: Loss of appetite, nausea, vomiting, fever, tiredness, pain in the upper right part of the abdomen, yellowing of the skin or eyes (jaundice), dark urine, or itching.
Action: Tell your prescriber promptly about any of these symptoms. Your prescriber will monitor your liver with periodic blood tests (and ultrasound scans for repeated treatment courses), since liver tumours can be silent until they cause sudden, severe internal bleeding. (1) (2)
Signs of a blood clot (thrombosis or thromboembolism), including stroke — emergency
Symptoms: Sudden severe headache, weakness or numbness on one side of the body, difficulty speaking, sudden vision changes, chest pain, shortness of breath, or swelling and pain in one leg.
Signs of raised pressure in the brain (benign intracranial hypertension / pseudotumor cerebri) — emergency
Symptoms: Severe or persistent headache, visual disturbances (such as blurred or double vision), nausea and vomiting.
Action: Seek prompt medical attention -- tell your prescriber immediately or seek emergency care if symptoms are severe. (1) (2)
Becoming pregnant while taking danazol — high caution
Symptoms: A missed period or a positive pregnancy test while taking danazol.
Action: Contact your prescriber immediately if you think you may be pregnant. Danazol exposure in pregnancy can cause serious androgenic effects on a female fetus -- your prescriber will advise you on next steps. (1) (2)
Interactions
- Warfarin and other anticoagulants: danazol can increase their blood-thinning effect, raising bleeding risk -- dose adjustment and closer monitoring may be needed. (1) (2)
- Carbamazepine, and likely phenytoin and phenobarbital: danazol can raise blood levels of these anti-seizure medicines. (2)
- Cyclosporin and tacrolimus: danazol can raise their blood levels, increasing the risk of kidney toxicity. (1) (2)
- Insulin or oral diabetes medicines: danazol can cause insulin resistance, and dosage may need to be increased to maintain blood sugar control. (2)
- Statins (simvastatin, atorvastatin, lovastatin): increased risk of myopathy and rhabdomyolysis (serious muscle breakdown) -- combination with simvastatin is contraindicated. (1) (2)
- Antihypertensive medicines: danazol may reduce their blood-pressure-lowering effect. (2)
Pregnancy, breastfeeding, kidney/liver function, age
Pregnancy
Contraindicated. Danazol can cause serious, sometimes irreversible androgenic effects on a female fetus if taken during pregnancy. A sensitive pregnancy test is recommended immediately before starting treatment, and a non-hormonal method of contraception must be used throughout therapy. (1) (2) (3) (4) (5) (6)
Breastfeeding
Contraindicated. Danazol has the potential for androgenic effects in breastfed infants -- your prescriber will help you decide between stopping danazol or not breastfeeding. (1) (2) (3) (4) (5) (6)
Children
Safety and effectiveness in children have not been established. (1) (2) (3) (4) (5) (6)
Elderly
Not specifically addressed in the sources reviewed for this dossier. (1) (2) (3) (4) (5) (6)
Hepatic_impairment
Contraindicated in markedly impaired liver function. Liver function is monitored periodically during treatment given the risk of hepatic dysfunction and rare liver tumours. (1) (2) (3) (4) (5) (6)
Renal_impairment
Contraindicated in markedly impaired kidney function. (1) (2) (3) (4) (5) (6)
Source_ids
US-DAILYMED-DANAZOL-2022,CA-HC-CYCLOMEN-PM-2017 (1) (2) (3) (4) (5) (6)
Monitoring
Before starting
- A sensitive pregnancy test immediately before starting treatment.
- Exclusion of breast carcinoma before treating fibrocystic breast disease.
- Baseline liver function and blood count.
During treatment
- Periodic liver function tests and haematological (blood count) tests.
- Biannual liver ultrasound for repeated or prolonged treatment courses.
- Watching for virilization, jaundice, signs of blood clots, and symptoms of raised intracranial pressure.
- Blood sugar monitoring in people with diabetes, due to insulin resistance.
Storage
Store at room temperature, away from moisture and heat, in the original container. Keep out of the reach of children.
Professional information
Clinician-facing context only, sourced from the current US FDA generic label and the Health Canada Cyclomen product monograph; verify against the current full label before prescribing.
United States
Indication: Endometriosis; hereditary angioedema prophylaxis
Dose summary: Endometriosis: 800 mg/day (moderate-severe) or 200-400 mg/day (mild) in divided doses, started during menstruation, for 3-9 months. Hereditary angioedema: 200 mg two to three times daily initially, titrated downward by 50% at 1-3 month intervals based on response.
Renal context: Contraindicated in markedly impaired renal function; not otherwise dose-adjusted in the source reviewed. (1)
Canada
Indication: Endometriosis; benign fibrocystic breast disease
Dose summary: Individualised dosing at the lowest clinically effective dose; endometriosis courses of 3-6 months (up to 9 in some cases); fibrocystic breast disease courses limited to 3-6 months. Concomitant simvastatin is contraindicated.
Renal context: Contraindicated in markedly impaired renal function. (2)
Hepatic guidance
Contraindicated in markedly impaired hepatic function. Periodic liver function tests and, for repeated courses, biannual hepatic ultrasonography are recommended given reports of peliosis hepatis, hepatic adenoma, and rare fatal fulminant hepatitis.
Overdose note
No specific antidote; manage supportively with monitoring, consistent with general management of an androgenic steroid overdose. (1) (2)
Frequently asked questions
Is danazol available in the US, UK, Europe, Canada, Australia, and New Zealand?
It is currently authorised and marketed in the United States (generic), the Netherlands within the EU (as Danatrol), and Canada (as Cyclomen). It was previously authorised but is now discontinued/cancelled in the United Kingdom (Danol, no current licensed UK product) and Australia (ARTG registrations cancelled in 2021). Its current status in New Zealand could not be verified from a live regulator source. (1) (4) (3) (2) (5) (6)
Can I take danazol if I am pregnant or trying to become pregnant?
No. Danazol is contraindicated in pregnancy because it can cause serious androgenic effects on a female fetus. Use a non-hormonal method of contraception throughout treatment, and contact your prescriber immediately if you think you might be pregnant. (1) (2)
What are the most serious risks of taking danazol?
Danazol carries several serious risks: virilizing effects (voice changes, excess hair growth, hair loss) that may not fully reverse after stopping; rare liver problems including peliosis hepatis and benign liver tumours, which can occasionally cause life-threatening internal bleeding; blood clots, including rare cases of stroke; and benign intracranial hypertension (raised pressure around the brain, with symptoms like severe headache and vision changes). Your clinician will monitor you, including periodic liver function and blood tests, throughout treatment. (1)
What is the mechanism of action of danazol?
Danazol is a synthetic steroid (attenuated androgen) that suppresses the pituitary-ovarian axis and inhibits pituitary gonadotropin output, reducing oestrogen production and inducing an atrophic, inactive endometrium; it also has weak androgenic, anti-androgenic, progestogenic, anti-progestogenic, oestrogenic, and anti-oestrogenic activity. (1) (2)
References
- Danazol capsules, USP -- full prescribing informationU.S. Food and Drug Administration / DailyMed (NIH), Abbreviated New Drug Application, Teva Pharmaceuticals USA, Inc. · United States · accessed 2026-07-29 · source 1
- Cyclomen (danazol capsules, USP) Product MonographHealth Canada product monograph, sanofi-aventis Canada Inc. · Canada · accessed 2026-07-29 · source 2
- Danol (danazol) -- UK licensing history and current discontinued statuselectronic medicines compendium (emc) historical SmPC (MHRA marketing authorisation PL 04425/0194) and patient.info clinical summary · United Kingdom · accessed 2026-07-29 · source 3
- Danatrol 100 mg capsules (danazol) -- Netherlands marketing authorisation (RVG 06982)College ter Beoordeling van Geneesmiddelen (Netherlands Medicines Evaluation Board) -- national marketing authorisation within the EU regulatory framework · European Union · accessed 2026-07-29 · source 4
- Danazol capsules -- ARTG cancellation notices and current PICMI searchTherapeutic Goods Administration (TGA), Australia · Australia · accessed 2026-07-29 · source 5
- Danazol -- Medsafe registration status (unable to verify)Medsafe (New Zealand regulator) -- search attempted, inconclusive · New Zealand · accessed 2026-07-29 · source 6
Brand names by country
Single-ingredient danazol names are shown separately by country. Product availability, strengths, and supply rules can change; combination products are not included here.
Priority countries
United States
- Danazol (generic) (1)FDA approved ANDA currently labeled · 50 mg, 100 mg, 200 mg · Teva Pharmaceuticals USA, Inc.
United Kingdom
- Danol (discontinued -- no licensed UK product currently available; accessible only as a specially manufactured/imported medicine) (3)MHRA licence PL 04425 0194 historical now discontinued · 100 mg (historical) · Sanofi (historical)
Canada
- CYCLOMEN
Australia
- Danazol Capsules / AZOL 200 (all ARTG registrations cancelled 19 March 2021; no current TGA-registered product) (5)TGA ARTG cancelled 2021 confirmed via live PICMI search · 100 mg (historical), 200 mg (historical) · Alphapharm Pty Ltd (historical)
New Zealand
- Not determined -- Medsafe's product database could not be queried directly in this research session, and no current data sheet was located; a legacy 'Azolcap' data sheet URL now 404s (6)unable to verify after genuine search attempt · not applicable · not applicable
View brands in additional countries.
European Union
Danatrol (4)