Over 65,000 tablets were seized last year as a result of enforcement investigations carried out by the Irish Medicines Board (IMB).
The investigations encompassed issues such as misleading advertising and the illegal sale and importation of prescription-only medicines over the Internet and by direct mail.
In total the IMB seized 65,044 tablets, 17,456 capsules, 2,971 grams of liquids and 6,525 grams of creams.
In a report on its performance last year, the board found an 8 per cent increase to 18,082 in the number of human medicines authorisations.
This included new products, renewals of licences for existing products and variations to existing products. The report also found that last year was the highest recorded for veterinary medicines' assessments.
The IMB said it has signed agreements with the US Food and Drugs Administration and the UK Medicines and Healthcare Regulatory Agency to allow early sharing of safety information leading to enhanced international co-operation between the agencies.