Nearly 20 million counterfeit Viagra pills have been seized by UK regulators in the last five years, as health chiefs warn against buying the little blue pills online. 

The number of tablets intercepted is the equivalent to a single dose for three quarters of men in the UK, and enough pills to fill two double-decker buses.  

Many of the pills seized were illegally sold online and contained no active ingredient, the wrong dose, or worse still - hidden drugs and toxic ingredients. 

Data from the UK regulator The Medicine and Healthcare products Regulatory Agency (MHRA), show 19.5 million doses of erectile dysfunction medicines were seized between 2021 and 2025. 

More than 4 million drugs were seized in 2025 alone, with the watchdog working closely with Border Force to intercept shipments and disrupt organised criminal networks. 

Erectile dysfunction medications are one of the most frequently seized illegally traded drugs in the UK, with rates more than doubling since 2022. 

Andy Morling, the MHRA's head of enforcement, said: 'Stigma and embarrassment are being exploited by criminals selling fake medicines that can seriously harm your health. 

'These seizures show the sheer scale of the illegal market for erectile dysfunction medicines in the UK - and the risks people are taking without realising. 

'Any medicine not authorised for sale in the UK can be unsafe and ineffective and there is no way of knowing what is in them or the negative health effects they can have.'

He added: 'These pills may look genuine, but many are potentially dangerous.' 

Sildenafil, sold under the brand name Viagra, is used to treat erection problems and works by temporarily increasing blood flow to the penis.

For it to work, a man must be sexually aroused. 

Drugs stocked in pharmacies in the UK must undergo strict quality control to ensure they are as safe as possible for people to use. 

While all erectile dysfunction medications carry potential side effects - including headache, nausea, indigestion and dizziness - drugs from unreliable sources may either be ineffective or contain toxins like heavy metals or other drugs that could be dangerous. 

Another reason to avoid buying these pills online is that the drug itself can be dangerous when taken incorrectly. 

According to the NHS, sildenafil may not be suitable for men taking medications for chest pain, who have a serious heart or liver problem or have low blood pressure. 

Reputable pharmacists will ask men interested in taking medications like Viagra a few questions about their health for this reason. 

More serious side effects requiring urgent medical attention are estimated to affect less than one in 1,000 men. 

These include seizures, suffering a prolonged and potentially painful erection for over two hours, chest pain, and in very rare cases, a life-threatening allergic reaction to the medication called anaphylaxis. 

Erectile dysfunction is thought to affect around 4.3 million men in the UK, including half of all men aged 40 to 70. One in 10 will experience erectile dysfunction at some point in their lifetime.

Despite this, research suggests two in five men would avoid seeking medical advice, pushing some towards unsafe online sellers.  

The MHRA warns: 'If you buy erectile dysfunction medicines from unregulated websites, social media or messaging apps, you are gambling with your health.' 

It added that anyone concerned about suspicious medicines or websites can report them through the Yellow Card scheme.