Association between myocarditis and antipsychotics other than clozapine: a systematic literature review and a pharmacovigilance study using VigiBase

Introduction: Pharmacovigilance studies have definitely established that clozapine can cause myocarditis. Two published reviews suggested that on rare occasions other antipsychotics may induce myocarditis. Areas covered: This review explored myocarditis associated with antipsychotics other than clozapine by conducting a systematic search of the literature and critically analyzing the current data in VigiBase compared to the data on clozapine-associated myocarditis. VigiBase is the World Health Organization’s global pharmacovigilance database that uses a statistical signal for associations with a logarithmic measure of disproportionality called the information component (IC). Expert opinion: For quetiapine, VigiBase provided 106 reports of myocarditis and a significant statistical signal (IC = 1.8; IC₀₂₅ = 1.5) which was confounded by 48% (51/106) with clozapine co-prescription. Combining the literature and VigiBase cases provided five probable myocarditis cases during quetiapine monotherapy (4 after overdose or rapid titration). For olanzapine, VigiBase provided 107 reports of myocarditis and a significant statistical signal (IC = 2.1; IC₀₂₅ = 1.8) probably explained by 77% (82/107) using clozapine co-prescription. Combining the literature and VigiBase cases provided one probable myocarditis case during olanzapine monotherapy. Combining the literature and VigiBase provided another three probable cases during therapy with other antipsychotics during overdose or titration with a high dose.