The pharmacologic interface between psychiatry and neurology is AEDs as they are utilized to treat both epilepsy and psychiatric disorders. Further, AEDs are commonly utilized to treat pain disorders. Thus, AEDs are primarily prescribed for treatment of psychiatric and pain disorders, not for treatment of epilepsy. The choice of which AEDs neurologists will utilize in treatment of epilepsy is most often premised on the classic benefits/risks/alternatives equation; however, consideration should be given to psychiatric co-morbidities and which AEDs might best serve patients in both maximizing seizure control and minimizing psychiatric symptoms as patients with epilepsy (PWE) have a 50-80% lifetime prevalence of psychiatric disorders with a three-to-five-fold increased risk of suicide compared to the general population. This overview of AED treatment of psychiatric disorders with inclusion of labeled and off-labeled uses can serve as a guide for neurologists and psychiatrists in better treating psychiatric co-morbidities in PWE.

Literature review.

Of 16 AEDs reviewed, clinical studies have addressed > 30 possible uses; however only 5 AEDs (benzodiazepines, carbamazepine, valproate, lamotrigine, and pregabalin) have received FDA/EMEA psychiatric indications. Most studies are uncontrolled case reports, open-label case series, and underpowered randomized controlled trials with methodological flaws. Regardless of the limited approved indications and in some instances negative pivotal trials, AEDs continue to be utilized adjunctively or in monotherapy treatment for a plethora of psychiatric diagnoses.

AEDs are pivotal in treating psychiatric co-morbidities in PWE. Further placebo-controlled (augmentation and monotherapy) parallel-arm research with active-comparators is required in this complex field.