The ringleader jailed for his part in the sale of fake drugs will remain incarcerated after losing an appeal against his sentence.

Ashish Halai, 34, of Borehamwood, was said to have been involved in the scam that netted millions of pounds through the plot to sell fake Viagra tablets and Cialis pills both used to treat male impotence, and Propecia, used to treat hair loss.

He was jailed for four and a half years in 2007 but lawyers have argued that the sentence was “manifestly excessive” as he had no previous convictions.

Lord Justice Toulson however decided that his sentence was appropriate since the accused was involved in “fraud on a grand scale” and described the scheme as a “sophisticated commercial enterprise”.

He went on to say that crimes like these “undermine the legitimate pharmaceutical companies and also damage public confidence in medicines. Sometimes it can give rise to an actual risk of health problems” so customers should be aware of how to buy Viagra safely online. “This enterprise was played for high stakes and high profits were realised. In our judgement, it merited a substantial custodial term for the main players.”

Every year millions of fake pills are sold on the internet to the US and other countries but some are also sold “legitimately” over the counter in UK chemists on prescription to unsuspecting customers who should be informed on where and how to get the blue pills safely.

The fake pills, produced in street factories in China and Pakistan, through distribution networks in Hong Kong, Dubai, the Bahamas and the UK have been traced by investigators.