Psychosis of epilepsy (POE) is a term applied to a group of psychotic disorders with a distinct phenomenology in which potential etiopathogenic mechanisms are believed to be closely related to a seizure disorder. POE can present as interictal psychotic episodes, which may often differ semiologically from primary schizophrenic disorder. They may present as ictal or postictal psychotic episodes and may be the expression of an iatrogenic process to pharmacologic and/or surgical interventions.Epilepsy and POE have a complex and bidirectional relation, as not only are patients with epilepsy at greater risk of developing a psychotic disorder, but patients with a primary psychotic disorder are also at greater risk of developing epilepsy. The prevalence of POE is more than 7 times higher than the frequency of primary schizophreniform disorders in the general population. While POE has been associated with focal epilepsy of temporal and frontal lobe origin, its etiology and pathophysiology of POE have yet to be established.The treatment of all forms of POE, with the exception of ictal psychotic episodes, requires the use of antipsychotic drugs, preferably the atypical antipsychotic agents with a very low or negligible potential to lower the seizure threshold (eg, risperidone, apiprazole), starting at a low dose with stepwise increments.

A 27-year-old woman presented to the emergency room after having witnessed generalized tonic clonic seizure while asleep. Birth and development were normal. She had suffered a single febrile seizure at 13 months of age, but had no other seizure risk factors. She was otherwise well except for a history of depression for which she was taking sertraline. Depressive symptoms had been well controlled over the past 3 months, but she had been under increased stress working to finish a doctoral thesis. Neurological examination was normal. Magnetic resonance imaging (MRI) showed modest asymmetry of the hippocampi, slightly smaller on the right, but no abnormal signal and well-preserved laminar anatomy. An electroencephalogram was negative. She was discharged from the emergency room with no treatment. Three weeks later, the patient's boyfriend witnessed an episode of behavioral arrest with lip smacking and swallowing automatisms lasting 45 seconds, after which the patient was confused for 20–30 minutes. The next morning she and her boyfriend kept a previously scheduled appointment with a neurologist.

Treatment options for epilepsy have increased in the last decade with the introduction of several new antiepileptic drugs (AEDs). As drug selection becomes more challenging, the use of evidence-based guidelines to aid in treatment decisions has become increasingly valued. The American Academy of Neurology's (AAN) guidelines for the use of new AEDs in refractory epilepsy offers many benefits, including expert panel recommendations based on clinically relevant questions with evidence-based responses. However, lack of evidence from randomized-controlled trials, particularly as they relate to monotherapy, limits the recommendations and their use in practice. The studies of new AEDs as monotherapy in treatment-refractory epilepsy are difficult to incorporate into clinical use because they are driven by Food and Drug Administration requirements to show superiority over placebo or pseudoplacebo (ie, low dose of active drug) rather than by clinical questions. However, based on Class I evidence, the AAN guidelines have granted Level A recommendations (established effectiveness) for oxcarbazepine and topiramate monotherapy, and a Level B recommendation (probable effectiveness) for lamotrigine monotherapy in the use of refractory partial epilepsy. There is insufficient evidence to recommend gabapentin, levetiracetam, tiagabine, or zonisamide monotherapy. No monotherapy AED trials have been conducted in refractory generalized epilepsy. Because no differences in efficacy have been reported for AEDs as initial therapy of partial seizures, differences in adverse events, such as weight gain, tremor, and hair loss, are key in drug selection. More comparative studies between the AEDs are necessary for both monotherapy and add-on therapy for treatment-refractory epilepsy.