Abstract
Amiodarone is commonly used for a variety of arrhythmias and, in some parts of the world, is the only available antiarrhythmic drug (AAD). Yet, amiodarone is known to have a wide range of potential side effects, many of which are dose- and duration-dependent. We sought to study the incidence of side effects leading to the discontinuation of low-dose amiodarone, arbitrarily defined as 200 mg/day or less, and very-low-dose amiodarone, defined as 100 mg/day or less. In this study, literature databases were searched through June 2019. Studies that reported the incidence or prevalence of side effects of amiodarone were included. Effect estimates from individual studies were extracted and combined using the random-effects generic inverse variance method of DerSimonian and Laird. A total of 10 observational cohort studies involving 901 patients were included in the analysis. The pooled estimated incidence of overall side effects for low-dose amiodarone was 0.17 [95% confidence interval (CI): 0.12-0.22]. In addition, the pooled estimated incidence of side effects requiring medication discontinuation was 0.06 (95% CI: 0.03-0.11). As compared with 200 mg/day of amiodarone, the pooled estimated incidence of overall side effects was 0.11 (95% CI: 0.04-0.27), while the incidence of side effects requiring medication discontinuation was 0.02 (95% CI: 0.01-0.06) for the dose of 100 mg/day. In conclusion, very-low-dose amiodarone displays a low incidence of significant side effects requiring medication discontinuation.