Masseter spasm after succinylcholine administration.

We report the case of a 20-year-old woman who developed masseter spasm after receiving succinylcholine for rapid sequence intubation. Sometimes referred to as "jaws of steel," masseter spasm secondary to anesthetic administration may progress to malignant hyperthermia. Although succinylcholine-induced masseter spasm is uncommon, it is important to be prepared to deal with this entity when administering succinylcholine.