What is cyproterone?

Medication that temporarily reduces the body's response to testosterone.

It's also known as Androcur.

What does cyproterone do?

• Body hair

  Prevents additional growth and may reduce and thin

• Facial hair

  Prevents additional growth and may reduce and thin

• Muscles

  Weakens and makes smaller

• Head hair

  Prevents some forms of hair loss

• Fertility

  Causes temporary or permanent infertility

• Lower body

  Causes genital shrinkage, reduces erections

• Face

  Softens skin, reduces acne

• Libido

  Reduces

• Fragrance

  Prevents change of body odour due to puberty

Who can have cyproterone?

• This is not recommended for use with under-18s, and must not be given before the end of puberty

• This is not normally available on the NHS, except as a temporary measure

How long does cyproterone last?

Cyproterone is taken as a tablet and effects last while the tablet is being taken. Prolonged use may have some effects that are permanent and cannot be reversed.

How do I stay safe?

If you’re taking cyproterone, you should also take at least a small dose of one of oestrogen or testosterone, to avoid osteoporosis. As with all hormones and hormone blockers, regular blood tests and monitoring are essential to spot any problems that arise.

Meningioma is a type of intracranial tumour, a tumour that forms in the membranous layers surrounding the brain and spinal cord. These are usually benign, but can cause a variety of problems due to the pressure they put on the structures of the brain and nervous system. The risk of meningioma linked to cyproterone is low, but increases with cumulative dose, meaning that the more cyproterone you have taken over the course of your life, the higher the risk.

Current government advice 2 states that you should not take cyproterone if you have a meningioma or a history of meningioma, and you should be vigilant for symptoms of meningioma, which are:

• Changes in vision
• Hearing loss or ringing in the ears
• Loss of smell
• Headaches that worsen with time
• Memory loss
• Seizures
• Weakness in extremities

However, just because you do not have any of these symptoms does not mean you don’t have a meningioma. If you are worried that you might have a meningioma, talk to your doctor.

What should I be aware of?

Cyproterone may cause erectile dysfunction. If this is not desired, it can be treated with sildenafil, tadalafil or vardenafil.

Are there other options?

In the UK GnRH (gonadotropin releasing hormone) agonists are generally prescribed instead, as they cause fewer side effects. These are described in more detail on the GnRH agonists page. In some cases, a short course of cyproterone is used in patients with testes receiving treatment with GnRH agonists to reduce the effects of the initial spike in testosterone levels caused by these medications 3, p.170.

How does it work?

Cyproterone acetate (Androcur) is a drug that reduces the amount that the body reacts to testosterone. It also reduces levels of the hormones that cause the body to produce testosterone 1, p.235.

References

1. 1.
   Seal, Leighton J (2017) “Hormone Treatment for Transgender Adults,” in Bouman, W. P. and Arcelus, J. (eds.), The Transgender Handbook: A Guide for Transgender People, Their Families and Professionals, Nova Science Publishers Inc, pp. 227–249. Link
2. 2.
   Medicines and Healthcare products Regulatory Agency (2020) “Cyproterone acetate: new advice to minimise risk of meningioma.” Link
3. 3.
   Seal, Leighton J (2007) “The practical management of hormonal treatment in adults with gender dysphoria,” in Barrett, J. (ed.), Transsexual and other disorders of gender identity: A practical guide to management, Radcliffe Publishing, pp. 157–190. Link
4. 4.
   FSRH Clinical Effectiveness Unit (2017) “Contraceptive Choices and Sexual Health for Transgender and Non-binary People.” Link

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