Top doctor says he’d never treat patients with hair-loss pill due to side effects that affect some ‘permanently’

A hair-loss treatment taken by Donald Trump causes impotence and depression in one in ten men, according to one of America’s top prostate surgeons.

Dr Edward Schaeffer, a consultant urologist who treated comic actor Ben Stiller for prostate cancer, says he does not recommend the drug finasteride ‘for any man’ due to the common side effects that affect some patients ‘permanently’.

The tablet, originally developed as a treatment for enlarged prostate, is now sold as Propecia and taken by millions of men across the globe, including the former president and various Hollywood stars, after it was proven to regrow hair.

It works by blocking the male hormone testosterone’s conversion to dihydrotestosterone, or DHT. High levels of DHT are believed to lead to hair loss by shrinking follicles on the scalp.

Finasteride is not prescribed for hair loss on the NHS but, earlier this year, The Mail on Sunday revealed the UK medicines regulators had opened an investigation into it amid a three-fold rise in reports of side effects such as depression, low libido and erectile dysfunction since 2020.

Finasteride is not prescribed for hair loss on the NHS but, earlier this year, The Mail on Sunday revealed the UK medicines regulators had opened an investigation into it

Government figures also show that finasteride has been linked with at least 70 reports of patients suffering suicidal thoughts as a suspected side effect.

The pharmaceutical firm which created finasteride, Merck & Co, has always denied links to serious long-term side effects, but also paid out millions of dollars to settle lawsuits with US patients.

How often these side effects – which have come to be known as post-finasteride syndrome – occur is still fiercely debated.

However, speaking to The Peter Attia Drive Podcast, Dr Schaeffer said he believed ‘about one in ten guys will have appreciable issues with this’. He adds: ‘The side effects from this post-finasteride syndrome are real. The duration can be highly variable. Some people will stop the medication and they’ll have resolution within a couple weeks, once the drug washes out. But there are people I know who have it permanently.’

Finasteride was first developed to treat enlarged prostates, but users soon saw hair-growth in tandem. When given in lower doses in studies, more than 80 per cent stopped losing their hair and 65 per cent saw it begin to grow back, often within months.

Initial studies suggested the drug was safe for use in treating hair loss.

About four per cent of those in the trial experienced temporary mental health problems and erectile dysfunction, which appeared to dissipate after they stopped taking the pills.

But in the past decade there has been growing evidence that post-finasteride syndrome affects thousands who take the drug.

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

And in March, this newspaper revealed the Medicines and Healthcare products Regulatory Agency (MHRA), the UK’s health safety watchdog, had opened an ongoing investigation into finasteride’s long-term effects.

Case reports appear to suggest younger men are affected more, which drug companies have used to correlate that post-finasteride syndrome is, in reality, a mental illness such as depression.

But Dr Schaeffer says older men experience it too, adding ‘It’s just they may be less interested in sex.’ He also argues that the severe side effects are likely due to the fact that finasteride lowers DHT levels in the body – which comes from testosterone.

‘Having that hormone around is critical for just about everything.’