The adverse event profile of zonisamide: a meta‐analysis

The first aim of our study was to analyze the adverse events statistically significantly associated with zonisamide, through a systematic review and meta‐analysis of available randomized placebo‐controlled trials ( RCT s). The second aim was to compare these results with those obtained from an analysis of non‐ RCT s and observational studies. Randomized controlled trials were identified using Medline (PubMed), EMBASE (Ovid), and Cochrane CENTRAL , from 1990 to September 2012. RevMan version 5.1 and OpenMeta[Analyst] were used for analyses of RCT and non‐ RCT s, respectively. Six eligible studies with 1184 patients between 12 and 80 years of age were included in RCT s analysis. Fifteen adverse events were investigated. In this first part of the analysis, no adverse events were statistically significantly associated with zonisamide. In the non‐ RCT analysis, a high incidence of weight loss and headache was found. In RCT s, zonisamide was statistically significantly associated with an increased risk of adverse event‐related study withdrawals [ RR (99% CI )  =  1.81 (1.07–3.08)]. Although our study revealed no statistically significantly associated adverse effects (AEs) with zonisamide, this is very likely a consequence of the small numbers in the RCT s available. The limited data available from the studies appear to reveal no major safety concerns related to zonisamide. However, the high incidence of weight loss and headache in the non‐ RCT s suggests that these AEs could be of clinical significance.