Malignant Hyperthermia (MH) is an inherited muscle disorder triggered by certain types of anesthesia that may cause a fast-acting life-threatening crisis.

The incidence of MH is low, but, if untreated, the mortality rate is high. Great advances in our understanding of MH have been made since it was first recognized in the early 1960s, but the nature of the fundamental defect(s) is still unknown.