Urgent alert for men taking Donald Trump's hair loss drug as health chiefs warn finasteride can trigger depression, insomnia, low libido and erectile dysfunction

Men taking a common hair loss drug were today warned about the risk of serious psychiatric and sexual side effects.

Safety concerns mean Brits must now immediately stop taking finasteride if they develop depression or suicidal thoughts. 

Health officials warn the daily pill, used by millions of men worldwide, might also trigger a low libido and erectile dysfunction. 

In some cases, the alarming effects persisted even after men stopped taking the drug in what patients have coined 'post-finasteride syndrome'.

Finasteride was famously taken by US President Donald Trump. It's prescribed on the NHS to men with an enlarged prostate. 

Safety concerns mean Brits must now immediately stop taking finasteride if they develop depression or suicidal thoughts. Health officials warn the daily pill, used by millions of men worldwide, might also trigger a low libido and erectile dysfunction. In some cases, the alarming effects persisted even after men stopped taking the drug in what patients have coined 'post-finasteride syndrome' 

Finasteride was famously taken by US President Donald Trump . It's prescribed on the NHS to men with an enlarged prostate.  But the exact number of users in the UK is unclear as the drug is not doled out for hair loss on the NHS , and is instead only available privately

But the exact number of users in the UK is unclear as the drug is not doled out for hair loss on the NHS, and is instead only available privately.

Warnings over finasteride's side effects follow a safety review by the Medicines and Healthcare products Regulatory Agency (MHRA), which polices the safety of drugs used in the UK.

It was sparked by a three-fold rise since 2020 in men reporting serious side effects including depression, insomnia, low libido and erectile dysfunction.

Dr Alison Cave, the MHRA's chief safety officer, said: 'It's crucial patients are aware of vital information about the medicines they’re taking.'

Alert cards warning over the potential side effects will be introduced into packets of finasteride later this year.  

Dr Cave added: 'The patient alert cards aim to raise awareness among men taking finasteride about the potential for psychiatric and sexual side effects, so they can make an informed decision about their treatment and know what to do if they experience these side effects.

'If you’re taking finasteride 1mg (Propecia) for hair loss and develop depression or suicidal thoughts, stop treatment and contact your doctor. 

'If these symptoms develop with finasteride 5mg (Proscar), for benign enlargement of the prostate, consult your doctor immediately for further advice. 

'Any concerns about sexual dysfunction should be discussed with your healthcare professional.

'Remember to always read the leaflet inside the pack because it includes important information on how to take finasteride and its possible side effects.'

Finasteride was originally developed by Merck and Co in the 1980s to treat having an enlarged prostate.

Users soon began to see unexpected hair growth, prompting it to be used for that reason.

It works by blocking the conversion of the testosterone into dihydrotestosterone, or DHT. DHT can cause the prostate to grow bigger.

High levels of DHT are believed to lead to hair loss by shrinking follicles on the scalp, hence why it can tackle hair loss.

Experts have previously suggested that the increase in side effect reports might be due to online companies selling finasteride to treat hair loss via private prescription. Men can order the drug online easily. 

The NHS says serious side effects are 'rare', occurring in below one in 1,000 people. 

Almost 4.1million prescriptions for an enlarged prostate were dispensed by GPs and other practitioners in England alone in the 2022/23 financial year, according to latest NHS data. 

Merck & Co has long denied any link with serious long-term side effects.

The US-based pharmaceutical firm has paid out millions of dollars to settle lawsuits with patients in America, however.

In 2021, Reuters reported it had obtained US court documents which showed that US watchdogs had received 700-plus reports of suicide and suicidal thoughts linked to the drug since 2011.

MHRA bosses received the first similar report in the early 90s.

Since then, it has had almost 300 reports of depressed mood disorders and suicidal and self-injurious behaviours linked to finasteride. 

More than 400 have also been associated with sexual dysfunction.  

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