Stringent epilepsy drug black-box labeling is likely to worry consumers and drug manufacturers alike, and will bring the total of drugs with a suicide risk warning up to about 35. The new warnings will be on the labels of 11 epilepsy drugs as soon as tomorrow, as FDA is very near finalization. Sales of the widely used drugs--which physicians also prescribe to treat migraines, certain types of pain and some psychiatric disorders--were over $8 billion last year.
The FDA made the decision to issue the warnings after analyzing data for nearly 200 trials of over 40,000 patients in a medication safety evaluation it initiated in 2005. They found that patients taking the epilepsy medications had almost double the risk of suicidal ideation or behavior compared to patients taking placebos. Additionally, while none of the individuals taking placebo medications committed suicide, four of those taking the epilepsy medications did.
The risk of suicidal thought and behavior increases after only a week of taking one of the medications and can last at least six months into it. The results were consistent regardless of the particular drug.
The medications affected include some neurology dinosaurs and include carbamazepine (Carbatrol, Equetro, Tegretol), felbamate (Felbatol), gabapentin (Neurontin), lamotrigine (Lamictal), levetiracetam (Keppra), oxcarbazepine (Trileptal), pregabalin (Lyrica), tiagabine (Lyrica), tiagabine (Gabitril), topiramate (Topamax), valproate (Depakote, Depakene, Depacon) and zonisamide (Zonegran).
Pfizer argued against inclusion on the list, saying that its drug, Lyrica, was different from others in the class. Lyrica is relatively new and might feel the black-box pain more than other drugs.