Complex sentence: Hyperthermia is a relatively rare side effect of many drugs, particularly those that affect the central nervous system while malignant hyperthermia is a rare complication of some types of general anesthesia.
Split into simpler sentences: Hyperthermia is a relatively rare side effect of many drugs, particularly those that affect the central nervous system. Malignant hyperthermia is a rare complication of some types of general anesthesia.