Malignant hyperthermia (MH) is a pharmacogenetic disorder triggered by exposure to halogenated volatile anesthetic gases and succinylcholine. The underlying mechanism for this potentially deadly condition involves the unregulated release of calcium from the sarcoplasmic reticulum into the myoplasm. The ryanodine receptor protein encoded by the RYR1 gene on chromosome 19q.13.1 forms the calcium channel (Figure 1).