Dantrolene sodium does influence the second-wind phenomenon in McArdle's disease. Electrophysiological evidence during exercise in a double-blind placebo-controlled, cross-over study in 5 patients.

Author(s): Poels PJ, Braakhekke JP, Joosten EM, Stegeman DF

Affiliation(s): Institute of Neurology, University Hospital Nijmegen, The Netherlands.

Publication date & source: 1990-12, J Neurol Sci., 100(1-2):108-12.

Publication type: Clinical Trial; Randomized Controlled Trial

Five patients with McArdle's disease entered a double-blind, placebo-controlled, cross-over study of dantrolene sodium. None of the patients experienced beneficial effect of dantrolene sodium medication. Each patient performed 2 exercise tests. Surface EMG during exercise tests without medication showed a temporary increase in EMG activity during the adaptation phase. Quite unexpectedly however, in view of the negative clinical results, this electrophysiological manifestation of muscle fatigue during the adaptation phase diminished or disappeared in all patients investigated when dantrolene sodium was used.