Clozapine discontinuation-induced catatonia: A detailed case report and exploration of potential underlying mechanisms

Background

While clozapine withdrawal side effects have been documented, few case reports have described its potential to cause withdrawal catatonia. Here, we present a case of a patient with schizophrenia who developed catatonia within seven days of clozapine discontinuation.

Case presentation

A 47-year-old male, with a history of schizophrenia on clozapine 600 mg daily, initially self-presented to the clinic for change in regimen, and was admitted to inpatient psychiatry due to disorganized thoughts. After a coincidental finding of urosepsis, he was transferred to the medical service for antibiotic treatment during which time clozapine was restarted. While infection improved, the patient became progressively less interactive and by day 7 was diagnosed with catatonia. Intramuscular lorazepam was trialed but led to oxygen desaturation requiring brief ICU monitoring, and resulted only in temporary improvement. Furthermore, patient displayed intermittent autonomic instability, concerning for malignant catatonia. He was ultimately transferred to another hospital for electroconvulsive therapy (ECT). Patient gradually returned to psychiatric baseline after 5 ECT sessions, re-titration of clozapine back to home dose, with short course of lorazepam as adjunctive therapy.

Conclusion

This case adds to existing evidence that clozapine discontinuation may induce catatonia. The current theory of the underlying mechanism involves clozapine's action at the GABAergic system through direct and indirect mechanisms and receptor changes with chronic clozapine use. Understanding this phenomenon helps inform decision-making with clozapine initiation and discontinuation and suggests potential treatment guidelines for catatonia in the context of clozapine withdrawal.