The Medicines and Healthcare products Regulatory Agency has strengthened safety warnings for finasteride and added fresh precautionary wording for dutasteride after what it describes as an additional detailed review of the evidence. The changes are set out in a new Drug Safety Update and in revised product information intended to give clearer direction to clinicians and patients. According to the MHRA, the latest action follows consideration of UK evidence alongside the outcome of a European regulatory review. The focus remains psychiatric side effects and sexual dysfunction, with the agency moving to more explicit risk communication rather than changing the medicines' licensed uses.
Finasteride is used in two common dose presentations with different routine purposes. The 1 mg product is used for male pattern hair loss, also described as androgenetic alopecia, while the 5 mg product is used in benign prostatic hyperplasia. Dutasteride 0.5 mg is also used in benign prostatic hyperplasia. The updated warning is most direct for finasteride 1 mg, reflecting concern about treatment in a population that may be using the medicine for a non-life-threatening condition over an extended period. For prescribers, that affects how benefit and risk are discussed before treatment starts and when side effects are reviewed.
For finasteride 1 mg, the MHRA says the product information will now state more clearly that sexual dysfunction may contribute to mood disorders. The revised wording also makes clear that sexual dysfunction has been reported both with and without associated mood alterations, making the warning more specific than before. For dutasteride, the agency has added a precautionary warning rather than the same direct statement used for finasteride. The new wording notes that mood alterations have been reported with finasteride, a medicine in the same class, and is intended to support caution when patients are assessed and monitored.
The patient-facing safety measures introduced for finasteride in 2024 remain in place. Existing patient alert cards continue to warn about sexual dysfunction, depression and suicidal thoughts, and they set out the action patients should take if symptoms emerge during treatment. The MHRA's advice to patients is unchanged in substance but clearer in presentation. Patients taking finasteride who experience depression or suicidal thoughts are advised to stop treatment and seek medical advice, while concerns about sexual side effects should be raised with a healthcare professional rather than left unmanaged.
For prescribers and pharmacists, the practical effect is a more explicit expectation that recognised risks are discussed before treatment is started and again if symptoms are reported. Dr Alison Cave, the MHRA's Chief Safety Officer, said the agency expects prescribers to go through the relevant safety information with patients so that treatment decisions are made on an informed basis. That is likely to be particularly relevant in primary care, dermatology, urology and remote prescribing settings, where finasteride may be supplied for hair loss as well as for benign prostatic hyperplasia. Updated product information will need to be reflected in counselling, prescribing templates and dispensing conversations, especially where patients may not volunteer mood changes or sexual adverse effects unless directly asked.
The regulatory background is also material. The MHRA says the latest amendments follow its 2024 safety review of finasteride, the continued use of patient alert cards introduced that year, the outcome of a European review under Article 31, and expert advice from the Commission on Human Medicines. For the medicines safety system, the change marks a shift from general awareness-raising to more detailed wording on how specific adverse effects may relate to one another. Suspected adverse reactions remain reportable through the Yellow Card scheme, which the MHRA continues to use as a key route for post-market safety monitoring.