The European Medicines Agency’s review of finasteride, which is available as both a pill and a solution that can be applied directly to the skin, follows concerns being raised about the potential link between the drug and thoughts of suicide. Finasteride can also be used to treat men with an enlarged prostate. Another drug, called dutasteride, also used to treat an enlarged prostate, is similarly under review by the EMA. 

Drugs containing finasteride and dutasteride when taken by mouth have a “known risk of psychiatric side effects, including depression,” said the regulator in a statement. Suicidal ideation has already been added as a possible side effect in the product information for two drugs containing finasteride — Propecia and Proscar.

Now, the EMA says it will review all the evidence to decide whether the authorizations for these drugs should be maintained, changed, suspended or withdrawn in the European Union.

Meanwhile, Britain’s drug regulator told men taking finasteride to “stay vigilant” for potential psychiatric and sexual side effects. The UK’s Medicines and Healthcare products Regulatory Agency said in April that a new patient alert card would be introduced into finasteride packs this year. Only oral finasteride is authorized in the UK, not the topical product. 

Generic finasteride is available from several manufactures, with brand name Proscar and Propecia both produced by Merck, known as MSD outside of North America.