Will the drug mexiletine (150mg three times daily) improve walking, myotonia (delayed grip
release), strength, pain, functionality, cardiac conduction irregularities, or quality of life in
participants after 3 and 6 months of treatment?
The study involves three visits with overnight stays at the University of Rochester. Travel
costs may be reimbursed up to $500 per visit. Study procedures include taking study drug
(mexiletine or placebo), a physical exam, collection of blood and urine samples, muscle
testing, questionnaires, EKGs, DEXA scans, and 24-hour Holter monitoring. There is no
cost to you to participate, and you will be provided
an honorarium after completing each visit.