Treatment of the interictal psychoses

Background: The interictal "schizophrenia-like" psychoses of epilepsy conve ntionally are treated with antipsychotic medication and uncertain results. In patients with these psychoses, a preceeding and concomitant dysphoric di sorder usually can be documented. Effectiveness of the pharmacologic treatm ent by the combination of drugs that is effective for severe interictal dys phoric disorders is demonstrated in a series of patients with interictal ps ychosis, Methods: Patients were treated with the combination of a tricyclic antidepr essant and a selective serotonin reuptake inhibitor, enhanced if necessary by a small amount of atypical neuroleptic risperidone. The series consisted of 8 consecutive patients with interictal psychosis seen over a 20-month p eriod. Two additional patients seen over the past 10 years who required a d ifferent therapeutic intervention were also included. Results: Five of the 8 consecutive patients achieved full remission of thei r psychosis; 3 patients could not be reached for the full treatment effort. One patient with a malignant psychosis had been treated successfully (prio r to the series reported) by surgical removal of a left frontal epileptogen ic zone; a second patient (treated after the series) recovered only upon el imination of the antiepileptic drug that had suppressed clinical seizures b ut had resulted in an alternating psychosis. Conclusion: Interictal psychoses can be viewed as severe interictal dysphor ic disorders with psychotic features. The same combination of psychotropic medication that is effective for severe interictal dysphoric disorders serv es as the primary therapy for interictal psychoses. The interictal psychiat ric disorders presumably result from seizure-suppressing mechanisms that ar e the targets of the proconvulsant drugs. Upon suppression of seizures, som e patients with interictal psychosis may require modification of the anti-e pileptic medication responsible for excessive inhibition. Complete surgical removal of the epileptogenic zone can eliminate a chronic interictal psych osis upon postoperative fading of inhibitory mechanisms.