Management of Rhabdomyolysis in a Patient Treated with Clozapine: A Case Report and Clinical Recommendations

Clozapine has a unique efficacy in treatment-resistant schizophrenia. Its use is, however, associated with potential adverse events. Among those, clozapine induced rhabdomyolysis can compromise clozapine treatment. Recommendations surrounding the management of this rare adverse event are limited. We present a case of clozapine-induced rhabdomyolysis. A 20-year-old Caucasian male diagnosed with resistant schizophrenia developed, after a 5-month total exposition and a significant response to treatment, a marked creatine kinase (CK) elevation and important myalgia in the weeks following an increment from 175 to 200 mg of the daily dose of clozapine. This event also coincided with weight training as reported by the patient. The patient was hospitalized, and the clozapine was stopped following the diagnosis of rhabdomyolysis (CK 45,564 U/L). The cause of rhabdomyolysis was thoroughly investigated, and clozapine was held accountable for most. Clozapine cessation led to a severe psychotic relapse. Clozapine rechallenge while strictly monitoring CK was then performed allowing a significant clinical response. Clozapine was pursued despite two other episodes of mild CK elevations observed following weight training. Rhabdomyolysis comes as a rare adverse event of clozapine and its mechanism is poorly understood. Evidence on clozapine rechallenge following this adverse event is lacking and the innocuity of such practice is unknown. The unique aspect of our case report is that a shared decision with the medical team, patient and family led to a proactive clozapine rechallenge. More research is needed to provide robust guidelines and evidenced based approaches for clinicians in such a clinical dilemma.