Nonhypoxemic hazards of prolonged myoclonus.

Hyperkalemia, hyperthermia, and systemic hypotension developed in a patient with generalized myoclonus. These disorders reached life-threatening proportions but were rapidly and completely corrected after the patient was paralyzed with pharmacologic agents. Induced neuromuscular blockade may be indicated when the systemic effects of pathologically contracting muscle become life-threatening.