The Irish Medicines Board has moved to reassure patients taking the blood thinning drugs Xarelton and Pradaxa following reports that 19 deaths have been linked to the drugs.
The medicines are used to reduce the risk of stroke and blood clots in patients.
IMB said reports of suspected adverse reactions cannot be used to conclude that there is an increased mortality rate for the drugs compared with the older standard drug Warfarin.
A report in the Sunday Business Post said the number of deaths associated with Xarelton and Pradaxa was three times higher than it is for Warfarin, although many more patients are taking Warfarin.
The Irish Medicines Board said that because Xarelton and Pradaxa are newer drugs on the market, a significant effort is made to request healthcare professionals and members of the public to report all reactions to them.
It said this is not the case with Warfarin, which has been on the market for 50 years.
It said it therefore attracts fewer reports because it is an established drug.