Supersensitivity psychosis in a case with clozapine tolerance

Despite its serious side effects, clozapine is still the golden standard in treat- ment of schizophrenia due to its effectiveness and lack of extrapyramidal side effects. Some studies have mentioned withdrawal symptoms, including withdrawal psychosis after stopping clozapine, and have tried to explain this severe symptom through dopamine receptor supersen- sitivity. This phenomenon, called supersensitivi- ty psychosis, can be explained by the develop- ment of tolerance towards the effect of the med- ication. In literature, there are several cases of supersensitivity psychosis while using other neuroleptics. However, to our knowledge, there are no published cases reporting an association between clozapine and supersensitivity psy- chosis. The current patient, who has been diag- nosed as resistant schizophrenia, responded well to the clozapine in the beginning of treat- ment. Due to an effective dose of clozapine, he had psychotic exacerbation with significant pos- itive symptoms. We discuss the probable rea- sons causing this situation and the relationship between tolerance to the treatment effect and the dopamine supersensitivity.