The FDA may beef up its warning for the anti-smoking drug Chantix after an increase in the number of serious incidents linked to the drug, the Wall Street Journal reports. A drug-safety group tallied 1,001 reports of patients suffering seizures, blackouts, and loss of motor control—some while driving—in three months. The figure is more than the combined total of incidents linked to the top 10 prescription drugs.
Pfizer says it will “stand by the efficacy and safety” of Chantix. It claims the reports are “unverifiable and lack sufficient medical information to draw any conclusions," and that nicotine withdrawal could be the culprit instead. The FDA already is reviewing Chantix for links to depression and suicidal behavior. Once nearing $1 billion in annual sales, Chantix sales stopped short of $100 million last quarter.