Commonly used antiepileptic drugs may increase the risk of suicide among patients who take them, the U.S. Food and Drug Administration warned Thursday.

Epilepsy is a common chronic neurological disorder that is characterized by recurrent unprovoked seizures. These seizures are transient signs and/or symptoms due to abnormal, excessive or synchronous neuronal activity in the brain. The disease is usually controlled, but not cured, with medication, although surgery may be considered in difficult cases.

The health organization analyzed almost 200 studies of 11 anti-seizure drugs, tracking almost 28,000 people given the medications and another 16,000 given placebo.

The analysis found patients treated with the drugs faced about twice the risk of suicidal thoughts or behavior compared to others who got a placebo: 0.43 percent of drug-treated patients experienced suicidal thoughts, compared with 0.22 percent of placebo-takers. Overall, four people who were taking one of the epilepsy drugs committed suicide, while none of the placebo patients did.

Based on these findings, the FDA concluded that for every 1,000 patients, about two more drug-treated patients experienced suicidal thoughts than placebo-takers.

“We have been looking at these drugs since 2005. We have just come to the conclusion that it’s time to alert health-care providers,” said FDA spokesperson Sandy Walsh, quoted by Forbes.

The 11 anti-seizure drugs included in the warning are: Carbamazepine (marketed as Carbatrol, Equetro, Tegretol, Tegretol XR), Felbamate (marketed as Felbatol), Gabapentin (marketed as Neurontin), Lamotrigine (marketed as Lamictal), Levetiracetam (marketed as Keppra), Oxcarbazepine (marketed as Trileptal), Pregabalin (marketed as Lyrica), Tiagabine (marketed as Gabitril), Topiramate (marketed as Topamax), Valproate (marketed as Depakote, Depakote ER, Depakene, Depacon) and Zonisamide (marketed as Zonegran). Some of these drugs are also available as generics.

Besides epilepsy, anti seizure drugs are also used to treat migraines, certain nerve-pain disorders and psychiatric disorders such as bipolar disorder that also carry a risk of suicide.

The health agency advised doctors and patients to weigh the risk against the potential benefits of the drugs and carefully supervise and notice any sign of depression, withdrawal from friends or family and thoughts of death or suicide in people who take these drugs. Symptoms can appear as quickly as a week after a patient starts treatment with one of the drugs and can persist for six months or longer, the agency said.

"All patients who are currently taking or starting on any antiepileptic drug should be closely monitored for notable changes in behavior that could indicate the emergence or worsening of suicidal thoughts or behavior or depression," the FDA alert said.

The FDA said it would be working with manufacturers of the antiepileptic drugs to include the new information in product labeling and it planned to discuss the data at an upcoming advisory committee meeting.

“We will be working with the companies to make sure the latest data is reflected in their prescribing information and labeling,” Walsh said.

Epilepsy Foundation Vice President John Schneider welcomed the FDA alert saying the problem is not a new issue,”it’s something that has been known for a long time.”

Patients were advised to ask a doctor before making medication changes, as skipping epilepsy medication can result in seizures. Dr. Cynthia Harden, a professor of neurology at Weill Cornell Medical College, said she would monitor her patients suffering from epilepsy more closely but would not end their treatment.
 
“The consequences of seizures are dire. There’s a risk of injury, even brain injury from a prolonged seizure, a loss of awareness and tremendous anxiety as these episodes can come without warning. It’s a very difficult illness to live with, and these drugs are well worth trying,” Dr. Harden said quoted by the New York Times.

About 2.7 million people in the United States have epilepsy, according to the U.S. Centers for Disease Control and Prevention. Globally, about 50 million have epilepsy at any given time, according to the World Health Organization.