TUESDAY, April 13, 2010 (Health.com) — Some antiseizure drugs used to treat epilepsy as well as depression, chronic pain, migraine, bipolar disorder, and other conditions are associated with a higher risk of suicide and violent death than other drugs in the same class, according to a new study.
Experts caution that patients should not stop taking the drugs—gabapentin (Neurontin), lamotrigine (Lamictal), oxcarbazepine (Trileptal), tiagabine (Gabitril), and valproate (Depakote)—without their doctor’s permission. It’s still not clear whether these risks are related to the drugs themselves or to underlying mood problems.
Suicidal thinking and acts are “very, very rare,” says Carl Bazil, MD, a professor of clinical neurology and the director of the Columbia Comprehensive Epilepsy Center, in New York City. “The vast majority of patients do not have anything like that.” Dr. Bazil was not involved in the research.
The study, published this week in the Journal of the American Medical Association, echoes a 2008 review by the U.S. Food and Drug Administration (FDA) that found that taking anticonvulsants (as this class of drugs is known) roughly doubled the risk of suicidal thoughts and suicide attempts, although the absolute risk remained small—less than half of 1%.
According to the FDA analysis, which included 11 anticonvulsants, the risk that a person taking those drugs would exhibit suicidal behavior or have suicidal thoughts was about 1 in 230, compared to about 1 in 450 in people taking a placebo, the FDA found.
As a result, the FDA required that the label of all anticonvulsants carry a warning about this increased risk. (The agency stopped short of requiring a so-called black box warning similar to those found on the labels of antidepressant drugs, however.)
The use of anticonvulsants has risen in recent years, among adults as well as children and teens. Doctors are increasingly prescribing the drugs off-label, meaning the drugs are not officially approved by the FDA for that condition.
In the new study, a team of researchers led by Elisabetta Patorno, MD, a research fellow at Brigham and Women’s Hospital, in Boston, looked at prescription data for 13 different anticonvulsants from health plans across the country and compared them to federal death records and data on emergency room visits and hospitalizations.
Of more than 2 million prescriptions filled in the five-year study period, the researchers looked at 297,620 new prescriptions. Among people who received the drugs, there were 801 suicide attempts, 26 suicides, and 41 violent deaths. (The researchers did not track suicidal thoughts, as did many of the trials considered by the FDA.)
Unlike the FDA report, which looked at the class of drugs as a whole, Dr. Patorno and her colleagues analyzed the risk of suicidal behavior associated with specific drugs. They compared the drugs to one in the class—topiramate (Topamax)—because it is widely used and prescribed for a range of conditions.
The risk of completed or attempted suicide among people taking tiagabine was 2.5 times greater than it was among those taking topiramate, while the risk among people taking oxcarbazepine was twice as great, the study found. The risk of completed or attempted suicide was also higher among people taking lamotrigine, valproate, or gabapentin, compared to topiramate. In all, 5 of the 12 drugs compared with topiramate were found to increase the risk of suicidal behavior.
Next page: Not all anticonvulsants are the same
