The terrifying dark truth about Viagra, the shocking side effect that can leave you impotent – and whether the little blue pill will really ‘turbocharge’ your sexual performance: PAT HAGAN

There was a time when erectile dysfunction was a dark secret that stayed very much in the bedroom. Not any more.

From that first TV ad with a bearded man in his blue, shorty PJs doing a post-Viagra dance seven years ago, now there’s a glut of social media content, on platforms such as TikTok – often with ‘funny’ takes on impotence and how to treat it.

Yet, while Viagra – aka the little blue pill – and similar drugs have transformed millions of men’s lives, they are not without risks.

Now experts are warning that young men are carrying these pills when socialising as a form of ‘back up’, to boost their sexual prowess.

Yet, in most cases, there is no legitimate medical reason for this – they’re getting hold of them either by telling a few white lies about their health to legitimate online pharmacies, or via less scrupulous websites where orders are rarely queried.

As a result, young men are easily able to obtain high-dose 100mg tablets, not realising that the more they take, the higher the risk of side-effects, including permanent damage that could leave them impotent and having to use a penile implant.

They’re also at greater risk of buying fake medicines that not only don’t work, as they contain none of the active drug, but do contain potentially toxic chemicals – as previous investigations have found.

There is no doubt that, for some, having the pill is like a form of insurance. ‘I know men who have Viagra in their wallet but never use it: it’s there just in case,’ says Lorraine Grover, a psychosexual nurse at the London Clinic, who has been treating men with erectile dysfunction on the NHS and privately for over 30 years.

‘I’ve even had patients who might just lick a tablet before sex – rather than swallow it – and that’s enough to give them the psychological boost they need to perform.’

Tet Yap, a consultant urological surgeon at the Lister Hospital in London, says he is aware of healthy young men who take it at weekends, in the belief it will turbo-charge their performance.

‘They think it will allow them to last for hours during sex and, then, when it doesn’t have much of an impact, they start to wonder if there is something wrong with them.

‘What many don’t realise is that, for a lot of men who take these drugs but don’t medically need them, any improvement is likely to be pretty minor.’

And one of the risks is a medical emergency called a priapism, an erection – often painful – that lasts for more than four hours and is not related to sexual stimulation.

Without emergency treatment to siphon off the blood from the penis, it can result in life-long impotence, says Mr Yap, explaining that ‘the sheer pressure from the high volume of blood rapidly makes the surrounding tissue fibrous’. This scarred tissue replaces the spongy, soft tissue that normally fills up with blood during arousal.

In 2019, Nat Thind, a 26-year-old from Hampshire, revealed he’d been left impotent after a ‘month-long’ erection caused by Viagra he’d bought over-the-counter. Doctors had to make a cut using a blade to drain the blood, but Nat claimed the op caused nerve damage which has left him with ‘a mutilated penis’.

‘A lot of young men without prompt treatment for priapism lose all their erections and end up needing a penile implant,’ says Mr Yap.

Reasons why young men may be affected by erectile problems include the rise in use of pornography (which may desensitise them to actual physical stimulation), binge drinking and drug-taking. But in some cases it may be due to underlying health issues such as undiagnosed type 2 diabetes – a major risk factor, as high blood-sugar levels can reduce blood flow to the penis.

In any of these circumstances, however, there is still a risk if young men get hold of impotence drugs without medical supervision. Indeed, young men under 18 were four times more at risk of a priapism than older men, according to a study published by scientists at the University of California San Francisco in January last year.

Viagra – or rather, the drug it contains, sildenafil – was originally developed for high blood pressure in the 1990s. After failing to meet expectations, it was given a new lease of life when men taking part in the clinical trials reported better erections – and a pharmaceutical blockbuster was born.

Today, NHS prescriptions for Viagra, and its numerous generic versions, are at near-record levels, at a cost of around £16.4 million a year.

In 2023, the last year for which figures are available, the NHS in England alone dished out 4.57 million prescriptions for sildenafil and other anti-impotence pills in the same class of medications – known collectively as phosphodiesterase type 5 (PDE5) inhibitors as they block the enzyme PDE5. These include Cialis (tadalafil) and Levitra (vardenafil).

Meanwhile, thousands more men in the UK are buying low-dose sildenafil over-the-counter from pharmacies – at around £4 per 50mg tablet, while many more are thought to buy from websites with a more relaxed approach to health vetting.

‘I’ve had patients come to see me who have been suicidal because of their erection problems and their lives have been transformed by taking Viagra,’ says Ms Grover. ‘Before it came along, all we had to offer were injections and vacuum pumps.’

Injections are every bit as unpleasant as they sound – a man must insert a needle directly into his penis to inject medicine that will relax the blood vessels so more blood flows into the area.

And vacuum pumps are just as much of a mood killer: the penis is placed inside a tube in the pump to create a vacuum that draws blood into the organ so it becomes erect.

‘Simply taking a tablet 30 minutes or so before sex [as in the case of sildenafil] is a more natural way to achieve arousal,’ says Ms Grover.

But for all its benefits, questions remain around safety.

Earlier this year, doctors warned about the dangers of using a fruit-flavoured jelly – sold online as Kamagra – which contains 100mg of sildenafil (the highest prescription-only dose). It melts in the mouth, where it is quickly absorbed into the bloodstream.

The jelly, which costs around £2.30, has been linked with the death of Australian cricket legend Shane Warne, who died of a heart attack, aged 52, while on holiday on the Thai island of Koh Samui in March 2022.

A post-mortem determined he died of ‘natural causes’ and suffered from congenital heart weakness that brought on a heart attack. However, a police official at the scene later claimed Kamagra was removed from Warne’s hotel room, raising speculation it may have been a factor in his death.

Some super-strength forms of the jelly also contain 60mg of dapoxetine, a prescription-only medicine sometimes given to men suffering from premature ejaculation. The drug is known to be unsafe for those with heart disease – though it’s not clear if this was the type found in Warne’s room.

Kamagra is illegal to buy or sell in the UK. But even legal versions of sildenafil – prescribed in the correct dose – can be dangerous for some.

The NHS says about one in 100 people will experience common side-effects, including headaches, nausea, hot flushes, indigestion, a stuffy nose and dizziness.

But some men are particularly at risk, including those with angina – where narrowing of the arteries around the heart causes episodes of chest pain.

‘If you have angina and are taking nitrates [commonly used to treat it], sildenafil combined with that can really cause a sharp drop in blood pressure,’ says Dr David Hutchings, an honorary consultant cardiologist at University of Manchester NHS Foundation Trust – this in turn increases the risk of dizziness, fainting and falls.

More serious side-effects, estimated to affect fewer than one in 1,000, include seizures, chest pain, and – in very rare cases – the life-threatening allergic reaction anaphylaxis.

Even vision can be affected – some users develop a bluish tint to their vision (called cyanopsia), because the drug also blocks another enzyme – PDE6 – which is found in the retina in the eye, and controls how light-sensitive cells there work.

And in very rare cases, PDE5 drugs, especially in high doses, can cause sudden blindness.

The drug’s original manufacturer, Pfizer, ultimately settled a series of 2006 lawsuits from men in the US who claimed that taking Viagra diminished blood flow to the optic nerve and caused permanent sight-loss called non-arteritic anterior ischemic optic neuropathy (or NAION). This risk is highest in men with high blood pressure or underlying heart conditions.

More recently, a 2020 paper in the journal Frontiers in Neurology by the World Eye Hospital in Adana, Turkey, reported on 17 healthy men who sought medical care after taking the drug for the first time, who all experienced vision disturbances, ranging from light sensitivity and blurriness to colour-blindness and blue-tinted vision.

All had taken the drug without prescription and at the highest recommended dose: 100mg. (Doctors usually suggest starting with 50mg, then raising or lowering as needed.) The symptoms continued after the drug’s erectile effects wore off, the scientists warned – sometimes for as long as three weeks.

Then there have been numerous studies linking prolonged use of Viagra and similar drugs with an increased risk of the potentially deadly skin cancer, malignant melanoma.

In the most recent analysis of data from more than two million men using sildenafil, scientists at Lutheran University of Brazil found they were 85 per cent more likely to develop a melanoma than men not on the drug.

It’s not clear why Viagra-type drugs might heighten skin-cancer risk, but studies suggest the enzyme PDE5 has an additional role in acting as a brake on the growth of melanoma cells.

Since Viagra was first licensed in the UK in 1998, there have been 3,582 adverse reactions from sildenafil reported to the MHRA Yellow Card scheme – the government database which allows patients and doctors to report suspected side-effects from prescription medicines.

In 192 cases, the patient died, including six teenagers, six men in their 20s, three in their 30s and 22 aged 40 to 49. Another 119 men over the age of 50 are also listed as having suspected fatal reactions to sildenafil.

The biggest cause of death is heart complications triggered by the drug. In five cases, the cause of death was suicide, thought to be triggered by taking sildenafil.

For rival drug tadalafil, first licensed in the UK in 2003, statistics record 1,325 suspected adverse reactions and 29 deaths.

The physical risks aside, experts warn that men using these drugs, but in particular young men who use it recreationally, run the risk of becoming dependent on it.

‘It’s known that taking it when not needing it for medical reasons can lead to psychological dependence – you feel like you need it when you don’t,’ says Mr Yap.

‘The good news is this means they should be able to wean themselves off and be just fine – their erections will return – but some might need psychosexual counselling to get them through that.’

Lorraine Grover concurs, adding: ‘Young men see Viagra and similar drugs as a quick fix, but the fact is no man should be taking these drugs without first being checked out by a doctor.’