Cyproterone


Generic Medicine Info
Indications and Dosage
Oral
Libido in severe hypersexuality or sexual deviation
Adult: For the reduction and control of sex drive in sexual deviations in men, only when other treatment options are considered inappropriate: 50 mg twice daily. When a satisfactory response is observed, gradually reduce dosage to the lowest effective dose to maintain therapeutic effect. Treatment duration must be according to individual response.

Oral
Palliative treatment of prostatic carcinoma
Adult: For the prevention of tumour flare with initial LH-releasing hormone (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 combined with LHRH analogue therapy for 3-4 weeks. For the long-term palliative treatment where LHRH analogues or surgery are contraindicated, not tolerated, or oral therapy is preferred: 200-300 mg daily in 2-3 divided doses. For the treatment of hot flushes in patients treated with LHRH analogues or after orchidectomy: Initially, 50 mg daily, if necessary, may be increased up to 150 mg daily in 1-3 divided doses.
Hepatic Impairment
Contraindicated.
Administration
Should be taken with food.
Contraindications
History or presence of meningioma, malignant tumours (except for prostate carcinoma), wasting diseases (except for inoperable prostate carcinoma), previous or existing liver tumours (if not due to metastases from prostate carcinoma), history or existing thromboembolic processes; Dubin-Johnson syndrome, Rotor syndrome; severe chronic depression, sickle-cell anaemia, severe diabetes with vascular changes. Hepatic impairment. Children (<18 years) or those with incomplete bone maturation and testicular development.
Special Precautions
Patient with diabetes mellitus or impaired glucose tolerance; CV disease, history of depression, pulmonary dysfunction, and chronic alcoholism. Not indicated for use in women. Renal impairment.
Adverse Reactions
Significant: Adrenocortical function suppression, single or multiple meningiomas (high dose and prolonged use), CNS depression (e.g. lassitude, weakness, fatigue), gynaecomastia, dermatologic effects (e.g. dry skin, transient alopecia), metabolic effects (e.g. serum lipid changes, hypercalcaemia, fluid retention), anaemia (prolonged use), shortness of breath, thromboembolic events, altered glucose metabolism; antiandrogen withdrawal syndrome. Rarely, hypochromic anaemia (prolonged use).
Gastrointestinal disorders: Nausea, vomiting.
Immune system disorders: Rarely, hypersensitivity reactions.
Investigations: Weight changes (increased or decreased), increased serum transaminases; reduced sperm count and volume of ejaculate.
Musculoskeletal and connective tissue disorders: Osteoporosis.
Nervous system disorders: Headache, restlessness (temporary).
Psychiatric disorders: Depressive mood.
Reproductive system and breast disorders: Azoospermia, decreased libido, erectile dysfunction, mastodynia, infertility. Rarely, galactorrhoea.
Respiratory, thoracic and mediastinal disorders: Dyspnoea.
Skin and subcutaneous tissue disorders: Rash, sweating.
Vascular disorders: Hot flushes.
Potentially Fatal: Hepatotoxicity (including jaundice, hepatitis, and acute hepatic failure). Rarely, benign and malignant hepatic tumours that may lead to intra-abdominal haemorrhage.
Patient Counseling Information
This drug may cause fatigue, lassitude, and asthenia, if affected, do not drive or operate machinery.
Monitoring Parameters
Perform LFTs prior to therapy initiation, regularly during treatment, and whenever signs and symptoms suggestive of hepatotoxicity occur. Monitor CBC before and at regular intervals during therapy; adrenocortical function, serum electrolytes, fasting blood glucose and glucose tolerance (in diabetics) periodically. Monitor for signs and symptoms of meningioma.
Drug Interactions
May affect carbohydrate metabolism, thus requirements for oral antidiabetics (e.g. pioglitazone) and insulin may be changed as necessary. Metabolism may be inhibited by CYP3A4 inhibitors (e.g. ketoconazole, ritonavir). CYP3A4 inducers (e.g. rifampicin, phenytoin) may reduce the levels of cyproterone. May increase the risk of rhabdomyolysis with HMG-CoA reductase inhibitors (statins).
Food Interaction
Alcohol may reduce the efficacy of cyproterone. May decrease the serum levels with St. John’s wort.
Action
Description: Cyproterone is a steroidal anti-androgen that also has anti-gonadotropic and progestin-like activity. It inhibits the binding of dihydrotestosterone (DHT) to prostatic cancer cells and exerts negative feedback on the hypothalamic receptors by preventing LH release, thereby reducing the production of testosterone.
Pharmacokinetics:
Absorption: Completely absorbed from the gastrointestinal tract. Bioavailability: 88%. Time to peak plasma concentration: 3-4 hours.
Distribution: Enters the breast milk. Plasma protein binding: 96%, mainly to albumin.
Metabolism: Metabolised in the liver via hydroxylation and conjugation into its primary metabolite, 15β-hydroxycyproterone.
Excretion: Mainly via faeces (60%); urine (33% as unconjugated metabolites). Elimination half-life: Approx 43 hours.
Chemical Structure

Chemical Structure Image
Cyproterone acetate

Source: National Center for Biotechnology Information. PubChem Database. Cyproterone acetate, CID=9880, https://pubchem.ncbi.nlm.nih.gov/compound/Cyproterone-acetate (accessed on Jan. 22, 2020)

Storage
Store between 15-30°C. Protect from light. Follow applicable procedures for receiving, handling, administration, and disposal.
MIMS Class
Cancer Hormone Therapy / Oestrogens, Progesterones & Related Synthetic Drugs / Oral Contraceptives
ATC Classification
G03HA01 - cyproterone ; Belongs to the class of antiandrogen preparations.
References
Androcur 50 mg Tablets (Bayer plc). MHRA. https://products.mhra.gov.uk/. Accessed 18/06/2020.

Anon. Cyproterone. Lexicomp Online. Hudson, Ohio. Wolters Kluwer Clinical Drug Information, Inc. https://online.lexi.com. Accessed 01/06/2020.

Buckingham R (ed). Cyproterone Acetate. Martindale: The Complete Drug Reference [online]. London. Pharmaceutical Press. https://www.medicinescomplete.com. Accessed 01/06/2020.

Cypron Tablet (Actavis Sdn Bhd). National Pharmaceutical Regulatory Agency - Ministry of Health Malaysia. https://www.npra.gov.my/. Accessed 01/06/2020.

Cyproterone Acetate 100 mg Tablets (Kent Pharma UK Limited). MHRA. https://products.mhra.gov.uk/. Accessed 01/06/2020.

Joint Formulary Committee. Cyproterone Acetate. British National Formulary [online]. London. BMJ Group and Pharmaceutical Press. https://www.medicinescomplete.com. Accessed 01/06/2020.

Restrictions in Use of Cyproterone Due to Meningioma Risk. European Medicines Agency [online]. Accessed 18/06/2020.

Rex Medical Ltd. Siterone Tablets data sheet 19 September 2018. Medsafe. http://www.medsafe.govt.nz/. Accessed 01/06/2020.

Disclaimer: This information is independently developed by MIMS based on Cyproterone from various references and is provided for your reference only. Therapeutic uses, prescribing information and product availability may vary between countries. Please refer to MIMS Product Monographs for specific and locally approved prescribing information. Although great effort has been made to ensure content accuracy, MIMS shall not be held responsible or liable for any claims or damages arising from the use or misuse of the information contained herein, its contents or omissions, or otherwise. Copyright © 2024 MIMS. All rights reserved. Powered by MIMS.com
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