Antidepressants in normal dosage may positively impact mood and seizure frequency

Epilepsy and depression are common co-morbidities. Concern for the potential of certain antidepressants to induce seizures has led to under-treating depression and anxiety disorders in epilepsy patients. Research presented today at the 66th American Epilepsy Society meeting suggests that antidepressants in normal dosage may have a positive impact on both mood and seizure frequency.

A research team at Rush University Medical Center, Chicago, conducted a retrospective study of 100 consecutive epilepsy patients started on selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs). The purpose of the study was to establish the impact of these antidepressants on seizure frequency, and to determine whether an improvement in seizure frequency correlated with a decrease in depression and anxiety.

Changes in mood and anxiety data were obtained at three and six months. Excluded from the analysis were patients who had had anticonvulsant drug or procedure changes at the time of antidepressant introduction. Improvements and/or remission of symptoms were observed in 86% of patients who continued in the study.

According to lead investigator Ramses Ribot, M.D., "SSRIs and SNRIs do not appear to worsen seizure frequency and yield a good therapeutic response independently of seizure frequency. Our studies also suggest these antidepressants may actually have an anti-seizure effect in patients with frequent seizures."

The findings are potentially of broad interest to treating physicians. However, the researchers say their findings need to be confirmed in prospective double-blind placebo-controlled clinical trials.