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This page explains about finasteride and its use, including side effects. You have been prescribed finasteride because you have been diagnosed with one of the following conditions: female pattern hair loss, lichen planopilaris, frontal fibrosing alopecia or hirsutism.

What is finasteride?

Finasteride is an inhibitor of 5-alpha reductase, an enzyme that converts (changes) testosterone to dihydrotestosterone (DHT) (the male hormones).

Finasteride is prescribed for conditions which are felt to be due to the accumulation (build up) of dihydrotestosterone (DHT) in tissues like hair follicles.

Use of finasteride in women

This medication is currently prescribed off label. This means that it is being used for a condition it was not previously meant to treat.

Finasteride has been prescribed by the consultant after careful consideration of other treatment options.

It is important to be aware that finasteride is classified as category X in pregnancy. This means that finasteride is not suitable for women who are likely to become pregnant, as it can change the levels of the male hormones which may affect a male baby’s development.

The recommend dose of finasteride is 2.5mg, sometimes a 5mg tablet is required in order to get the desired effect.

Side effects of finasteride

  • Mood changes (anxiety and depression) in 1 in every 150 patients.
  • Difficulty concentrating (this is rare).
  • Enlargement of breast tissue and sometimes breast tenderness (this is rare).

Other side effects may be possible but many patients take finasteride without any side effects.

If you develop any side effects while taking finasteride, please contact Dr Takwale’s secretary. The contact details are at the end of this page.

Important points to remember

  • Finasteride must not be used in pregnancy or when breastfeeding as there is no research to suggest that it is safe to do so.
  • You must not donate blood while taking finasteride. If a pregnant woman needed a blood transfusion the presence of finasteride in the donated blood could impact the baby’s development.
  • Please read the patient information leaflet enclosed with the medication.

Contact information

Dr Takwale’s Secretary

Tel: 0300 422 5396

Monday to Friday, 9:00am to 3:00pm

Printable version of this page

Finasteride for women GHPI1510_02_25 Department: Dermatology Review due: February 2028 PDF, 315.5 KB, 3 pages
Reference number GHPI1510_02_25
Department Dermatology
Review due February 2028