Adult: For control or reduction of libido in pathologically altered or increased sexuality in men: 50 mg bid. Dosage and treatment recommendations may vary among countries and between individual products (refer to specific product guidelines).
Oral Palliative treatment of prostatic carcinoma
Adult: For long-term palliative treatment where luteinising hormone-releasing hormone (LHRH) analogues or surgery are contraindicated, not tolerated, or when oral therapy is preferred: 200-300 mg daily in 2-3 divided doses. Max: 300 mg daily. For the suppression of tumour flare with initial LHRH analogue therapy: Initially, 200 mg daily in 2-3 divided doses alone for 5-7 days, followed by 200 mg daily in 2-3 divided doses in combination with LHRH analogue therapy for 3-4 weeks. Max: 300 mg daily. For the treatment of hot flushes associated with LHRH analogues or after orchidectomy: Initially, 50 mg daily, may be increased up to 150 mg daily in 1-3 divided doses based on response. Dosage and treatment recommendations may vary among countries and between individual products (refer to specific product guidelines).
What are the brands available for Cyproterone in Singapore?
Androcur
Hepatic Impairment
Contraindicated.
Administration
Cyproterone Should be taken with food.
Contraindications
History or presence of meningioma, malignant tumours (except for prostate carcinoma), previous or existing liver tumours (if not due to metastases from prostate carcinoma), wasting diseases (except for inoperable prostate carcinoma), existing or history of thromboembolic disorders, Dubin-Johnson syndrome, Rotor syndrome. When used for hypersexuality: Severe chronic depression, severe diabetes with vascular changes, sickle-cell anaemia. Hepatic impairment.
Special Precautions
Patient with diabetes, pulmonary dysfunction, and chronic alcoholism. Not intended for use in patients who can become pregnant.
Adverse Reactions
Significant: Single or multiple meningiomas (during chronic use, mainly at doses of ≥25 mg/day); suppression of adrenocortical function; metabolic effects (e.g. changes in lipid profile, fluid retention); shortness of breath (at high doses); anaemia, gynaecomastia; may increase risk of thromboembolic events; CNS depression (e.g. lassitude, weakness, fatigue). Cardiac disorders: Tachycardia. Gastrointestinal disorders: Nausea, vomiting. Immune system disorders: Rarely, hypersensitivity reactions. Investigations: Weight changes (mainly weight gain). Musculoskeletal and connective tissue disorders: Osteoporosis. Nervous system disorders: Headache. Psychiatric disorders: Depressive moods, restlessness. Reproductive system and breast disorders: Infertility, decreased libido, erectile dysfunction, azoospermia. Rarely, galactorrhoea and benign nodules. Skin and subcutaneous tissue disorders: Rash, sweating, dry skin, transient alopecia. Vascular disorders: Hot flush. Potentially Fatal: Hepatotoxicity, including jaundice, hepatitis and hepatic failure (for doses of ≥100 mg/day). Rarely, benign and malignant liver tumours which may lead to intra-abdominal bleeding.
Patient Counseling Information
This drug may cause tiredness and weakness, if affected, do not drive or operate machinery.
Monitoring Parameters
Obtain LFTs at baseline, regularly during therapy, and if any signs or symptoms of liver toxicity occur. Monitor adrenocortical function (regularly during treatment); CBC (at baseline and periodically during treatment); electrolytes; fasting blood glucose and glucose tolerance (in patients with diabetes; at baseline and regularly during treatment). Assess for signs or symptoms of depression and meningioma (e.g. changes in vision, hearing loss, ringing in the ears, memory loss, seizures, weakness in the arms or legs).
Drug Interactions
May increase serum concentration with strong CYP3A4 inhibitors (e.g. ketoconazole, itraconazole, ritonavir). May reduce serum concentration with CYP3A4 inducers (e.g. rifampicin, phenytoin). Increased risk of statin-associated myopathy or rhabdomyolysis with HMG-CoA inhibitors.
Food Interaction
Alcohol may decrease the effect of cyproterone. St. John's wort may reduce the serum concentration of cyproterone.
Action
Description: Overview: Cyproterone is a progestogen with antiandrogenic, progestin-like and antigonadotrophic effects. Mechanism of Action: Cyproterone prevents dihydrotestosterone (DHT) from binding to prostate cancer cells and suppresses luteinising hormone (LH) secretion through negative feedback on the hypothalamic-pituitary axis. Pharmacodynamics: Cyproterone reduces the release of gonadotrophin and consequently diminishes testicular androgen production. It inhibits gonadal function and decreases sexual drive and potency. When used in combination with LHRH analogues, cyproterone reduces the initial increase of testosterone caused by these analogues. Pharmacokinetics: Absorption: Completely absorbed from the gastrointestinal tract. Bioavailability: 88%. Time to peak plasma concentration: 3-4 hours. Distribution: Enters breast milk. Plasma protein binding: Approx 96%, primarily to albumin. Metabolism: Metabolised in the liver via various pathways, including hydroxylation and conjugation pathways, into 15β-hydroxycyproterone (main metabolite); phase I metabolism is mainly catalysed by CYP3A4. Excretion: Via faeces (60%); urine (33%; mainly as unconjugated metabolites). Elimination half-life: 38 ± 5 hours.
Chemical Structure
Cyproterone Source: National Center for Biotechnology Information. PubChem Compound Summary for CID 5284537, Cyproterone. https://pubchem.ncbi.nlm.nih.gov/compound/Cyproterone. Accessed Oct. 29, 2025.
Sign Out
Continue with Google