The most recent analytical report by the Institute for Safe Medical Practices (ISMP) found that anticoagulant drugs dabigatran (brand name Pradaxa), and warfarin (branded name Coumadin) generated the most adverse event reports during 2011.
Dabigatran received 817 reports and warfarin received 490.
The FDA received 179,855 reports of serious side effects or fatal drug events in total during 2011, according to the ISMP report.
The non-profit ISMP and a handful of commercial firms use raw FDA Adverse Event Reporting System (AERS) data to compile reports on drug side effects.
Using the FDA data, the ISMP extrapolated that between 2 and 4 million people encountered a serious side effect or fatality as the result pf prescription drug use during 2011.