The FDA released the results of an analysis of 11 anticonvulsant drugs used primarily for seizures and certain psychiatric conditions in January, which found double the risk of suicidality associated with the drugs. Accordingly, the FDA voted that risks be described in a medication guide that patients taking the drugs would be provided. The FDA has yet to issue a black box warning due to concerns that such a warning would prevent physicians from prescribing such drugs to those that need them. However, Russell Katz, M.D., director of neurology products for the FDA’s Center for Drug Evaluation and Research, said that the FDA may still issue a black box warning. The following is an excerpt of an article from Medpage Today that discusses the FDA’s findings:
The drugs evaluated were carbamazepine (Carbatrol, Equetro, Tegretol, Tegretol XR), felbamate (Felbatol), gabapentin (Neurontin), lamotrigine (Lamictal), levetiracetam (Keppra), oxcarbazepine (Trileptal), pregabalin (Lyrica), tiagabine (Gabitril), topiramate (Topamax), divalproex sodium (Depakote), and zonisamide (Zonegran).
A meta-analysis of 199 placebo-controlled trials consisting of 27,863 patients on active treatment and 16,029 on placebo found that 0.37% of those receiving one of the 11 drugs and 0.22% of those taking placebo had suicidal ideation or behavior (OR 1.80, 95% CI 1.24 to 2.66).
For three of the drugs, there was no increased risk for suicidality — carbamazepine (OR 0.66), felbamate (OR not defined), divalproex (OR 0.91). The elevated risk only reached nominal significance for two of the other eight.
Dr. Katz explained why the agency and the committees concluded that the warnings should be applied to all epilepsy drugs.
The committee members “felt that the signal occurred across a whole range of drugs with different mechanisms of action,” he said, “so it’s perfectly reasonable to conclude that the other drugs that weren’t studied were likely to show the same signal.”