PATIENTS WITH NONDYSTROPHIC MYOTONIAS TYPIcally have myotonia as an isolated symptom, without muscular wasting, although the patient’s myotonia may be associated with muscle weakness and fatigue or transient attacks of paralysis. Episodes of myotonia may be triggered by cold (paramyotonia congenita), potassium (potassium aggravated myotonia), or exercise (Thompson and Becker myotonia). Most cas...