Exercise test in the inter-attack period of thyrotoxic periodic paralysis: a useful diagnostic tool.

Exercise test was reported to be useful for some patients with periodic paralysis. We report here the results of exercise test in three cases of thyrotoxic periodic paralysis, for whom the exercise test was all positive. Exercise test could be one of the diagnostic tools in the "inter-attack" state of the probable cases with thyrotoxic periodic paralysis. However, the case number of this study is small and larger-scale studies may be warranted in the future.