"Self-taming" of suxamethonium and serum potassium concentration.

Fifty patients undergoing routine surgery were randomly divided into two groups. Group 1 were pretreated with a small (10-mg) dose of suxamethonium ("self-taming") before administration of suxamethonium 1 mg kg-1, while group 2 received no pretreatment. Potassium concentrations were measured immediately before induction of anaesthesia and, subsequently, for 7 min. A small increase in mean plasma potassium concentration was seen in the group who were not pretreated, while the patients who received a "self-taming" dose of suxamethonium showed a sustained decrease below pre-induction values. Mean plasma potassium concentrations were significantly less in the "self-taming" group than in the group not pretreated.