Carbamazepine as an adjunct in the treatment of schizophrenia-like psychosis related to cannabis abuse.

The efficacy of an adjuvant application of carbamazepine in cannabis-related schizophrenia-like psychosis not responsive to neuroleptic treatment is reported for the first time. In two patients, psychotic states occurred after continuous cannabis consumption over a period of 8 and 18 months, respectively, which were mainly characterized by severe thought disorders, disturbances of perception, delusions and weak affect. Both patients were admitted to hospital with no previous clinical history of psychotic episodes. After nonresponsive treatment with neuroleptics over several weeks, they both rapidly responded to additional medication with carbamazepine within a week after onset with a marked reduction in clinical signs and symptoms.