"...Pfizer's Chantix (varenicline), already under fire for safety issues, was targeted again late last week when the Institute for Safe Medication Practices, a nonprofit best known for its work in preventing medication errors, reported that the smoking cessation product was associated with more serious adverse event (SAE) reports than any other drug.
The report looked at US adverse event reports received by FDA in the fourth quarter of 2007. During that period, only 35 drugs accounted for 100 or more SAE reports. (FDA received reports on 769 drugs in the period; the median number of SAE reports per drug was five.)
Chantix logged 998 reports, followed by interferon beta (640), etanercept (555), infliximab (554), fentanyl (404), and oxycodone (372)..."