Medical authorities in Ireland seized a large number of unauthorised medicines during 2009, most of them sourced from India.
Among the products that arrived by mail and were seized included those containing active substances such as Diazepam, Tadalafil (used for the treatment of erectile dysfunction) and testosterone and weight-loss products.
The Irish Medicines Board initiated 3,729 enforcement cases in relation to medicines, the majority of which related to the importation of prescription-only medicine via mail
The total amount of unauthorised medicines seized last year represents a 19 per cent rise in 2008 figures, reports from Dublin said.
Almost half a million tablets and capsules were seized by IMB staff in conjunction with Revenue's Customs officers as well as 1,650 packs of liquids, 449 packs of creams and 3,582 packs of assorted unauthorised products.
The majority of unauthorised products supplied in Ireland originated in India.
The IMB chief executive Pat O'Mahony said staff had identified over 1,000 websites offering to supply medicinal products into Ireland illegally.
He warned the public against the dangers of buying medicines online as there are no guarantees to the safety, quality, effectiveness and authenticity of such products.
He said: "In fact, medicines purchased on the internet can pose serious health risks to those who use them. The supply of prescription-only medicines via the internet is illegal and no online pharmacy is authorised to operate in Ireland."