Mexiletine use investigated in non-dystrophic myotonias

New findings from a multicenter study have highlighted the potential benefits of the class Ib antiarrhythmic agent mexiletine in the treatment of non-dystrophic myotonias.

Dr Savine Vicart and colleagues from Hôpital de la Pitié-Salpêtrière, Paris, France, presented results from the randomized, double-blind, placebo-controlled MYOMEX study on the efficacy and safety of mexiletine. 

The study group included 24 patients (12 myotonia congenita and 12 paramyotonia congenita patients) who were treated with mexiletine for a period of 18-22 days, starting at 200 mg/day, increased by 200 mg every 3 days until the dose reached 600 mg/day.