Asaad Hussain, 40, from Hawarden Avenue in Leicester, has been given a 450 day prison sentence after failing to pay a £35,000 confiscation order imposed on him after he was found guilty of illegally selling prohibited herbal medicines last year.

Mr Hussain was given six months to pay the order following his conviction in February 2010, but after failing to do so received a prison sentence at Leicester Magistrates Court last week, the MHRA reported.

At his original trial, Mr Hussain pleaded guilty to two offences of unlawfully selling a medicinal product. This came after the MHRA had seized more than 4,400 containers of prohibited herbal tablets, as well as promotional leaflets, in two separate raids on his property.

In October 2006, the agency had seized almost £135,000 worth of illegal herbal medicines during a raid on Mr Hussain's property in Leicester, where he had been running an illicit online pharmacy.

Mr Hussain had been selling Pauinystalia Yohimbe, a prohibited herbal sexual dysfunction drug labelled as Extensis.

In January 2008, Mr Hussain was found to have continued to sell the product. The MHRA seized promotional boxes and leaflets  and discovered that that 45 bottles, worth £2,137, had been sold between November and December 2007, with a further 389 bottles in stock "waiting to be sold".

Following his original trial, Mr Hussain received a £1,000 fine, £4,000 prosecution costs as well as a £35,000 confiscation order. He failed to pay the money despite "multiple attempts" made by the court to obtain it, an MHRA spokesperson said.

The agency said Mr Hussain's subsequent prison sentence highlighted how seriously the MHRA and judicial system took the illegal sale of prohibited and unlicensed herbal medicines.