Prescriptions for Viagra and similar drugs almost trebled in a decade, with nearly three million given out last year.
Doctors said the pills have become particularly popular with young men who watch porn and feel pressure to perform.
They also cited less stigma and lower cost as reasons for the rise.
NHS Digital figures show 2,958,199 prescriptions for erectile dysfunction treatments in 2016, up from 1,042,431 in 2006.
The price of Viagra-type drugs fell in 2013 when manufacturer Pfizer’s ‘patent’ – the exclusive rights to make it – expired. Previously, a pack of four Viagra pills by Pfizer had cost £21.27. By 2014, a pack of four generic pills with the same ingredient, sidenafil, was £1.45.
Dr Seth Rankin, of the London Doctors Clinic, said many men in their 20s and 30s took Viagra because they watched a lot of porn and felt pressure to perform, or to counteract the effect of alcohol or drugs.
Professor Helen Stokes-Lampard, of the Royal College of GPs, warned against buying the drug online without seeing a GP.
© Daily Mail