Patients with epilepsy seem particularly liable to certain major psychiatric disorders. Prevalence of schizophrenia within an epileptic population varies between 3% and 7% (1% in general population). The aetiology is possibly multifactorial (drugs and neurosurgery).

To study comorbidity between psychoses and epilepsy and management in the literature and in our patients.

To analyze factors that might influence the onset of psychoses within an epileptic population and how this potential association could influence our practice.

PubMed search was conducted with interest in psychoses of epilepsy, pharmacology, and comorbidity. Up to 10 variables related with factors influencing psychotic episodes that required hospital admission in three patients with epilepsy were studied.

Unlike published data, our patients did not have postictal psychoses. All cases had early onset temporal lobe epilepsy with no seizure activity since diagnosis (more than 20 years). No family history of either epilepsy or psychoses. Management included lamotrigine, oxcarbazepine, carbamazepine, zonisamide, and levetiracetam in conventional doses. The psychosis, which comprised affective, schizophrenic, and confusional elements, lasted longer and was more troublesome than psychosis in non-epileptic patients. Response to neuroleptics was poorer than in non-epileptic patients with psychoses. Consultation with Neurology Unit resulted in end of treatment with zonisamide and levetiracetam.

Less than perfect evidence suggests the association between psychosis and epilepsy. In our patients, no postictal cases were recorded. Management showed poorer effect of neuroleptics when compared with non-epileptics, and zonisamide and levetiracetam were changed for other drugs with presumably lower association with psychoses.

The authors have not supplied their declaration of competing interest.