Abstract

Background: Clozapine is the most effective antipsychotic for treatment-resistant schizophrenia, and abrupt discontinuation can lead to severe neuropsychiatric destabilization, including withdrawal catatonia. High-potency dopamine D2 receptor antagonists may further precipitate neuroleptic malignant syndrome (NMS), a condition with substantial clinical overlap with malignant catatonia. Objective: This report follows CARE guidelines to provide a structured and transparent description of a complex case involving abrupt clozapine withdrawal and rapid antipsychotic transition. Case presentation: This report describes a male patient with schizophrenia who developed malignant catatonia with overlapping NMS features following abrupt clozapine withdrawal and initiation of fluphenazine. Conclusion: The case underscores the importance of cautious antipsychotic transitions and early recognition of catatonia and NMS.

Key words: catatonia; clozapine withdrawal; neuroleptic malignant syndrome