Biomechanics and Motion Analysis

Medication Trial for Patients with Periodic Paralysis

Principle Investigators: Robert C. Griggs M.D. and Rabi Tawil, M.D.
Project Coordinator: Diane Serfling, PT — serfling.diane@mayo.edu

Periodic paralysis is a group of rare genetic diseases that lead to weakness or paralysis (rarely death) from common triggers such as cold, heat, high carbohydrate meals, not eating, stress or excitement and physical activity of any kind. The underlying mechanism of these diseases are malfunctions in the ion channels in skeletal muscle cell membranes that allow electrically charged ions to leak in or out of the muscle cell, causing the cell to depolarize and become unable to move (a channelopathy). Patients with this diagnosis will have periods of weakness that generally are felt to completely resolve, sometimes in a matter of hours.

Participants for this study have a diagnosis of periodic paralysis and have distinct regular episodes of weakness with an average frequency of >1/week and <3/day either on or off treatment, whichever is higher.

The Mayo Clinic and the Motion Analysis Laboratory are participating in a multi center study to evaluate the ability of two medications, dichlorphenamide (DCP) or acetazolamide (ACZ) to lower the rate of periodic paralysis attacks. The study will also be looking at whether the drugs will have an affect on strength, muscle mass, physical health, and mental health. This is a 9 week study, with a one year follow-up. The Motion Analysis Laboratory will be measuring strength using both manual muscle testing and quantitative strength testing.