Health System Pharmacist Protocol for Myocarditis Monitoring in Clozapine-Naïve Inpatients—Two Years’ Experience

OBJECTIVE: To describe the implementation and efficacy of a pharmacist-driven clozapine myocarditis monitoring protocol including 2 cases of clozapine-induced myocarditis identified using this protocol. METHODS: In February 2015, the health system formulary committee approved changes to an existing pharmacist-driven protocol to allow for myocarditis monitoring in patients initiated on clozapine therapy based on an algorithm published by Ronaldson et al in 2011. The monitoring includes the measurement of C-reactive protein (CRP; via high-sensitivity CRP [hsCRP] serum test) and troponin at baseline and then weekly for 4 weeks. Patients initiated on clozapine therapy between March 2015 and February 2017 and monitored according to the aforementioned protocol are described in this article. RESULTS: A total of 38 patients were initiated on clozapine therapy during the specified data collection period. Of these 38 patients, 4 screened positive for early signs of myocarditis according to the monitoring protocol, and 2 of those 4 patients were confirmed by cardiology consultation to have clozapine-induced myocarditis. Both of these patients experienced a full cardiac recovery upon discontinuation of clozapine. CONCLUSION: A pharmacist-driven myocarditis monitoring protocol for clozapine-naïve patients may help to identify early signs of clozapine-induced myocarditis and therefore mitigate potentially life-threatening complications by prompting early discontinuation of the inciting drug.