FDA OKs Injectable Dantrolene for Malignant Hyperthermia

The US Food and Drug Administration (FDA) has approved an injectable form of dantrolene sodium (Ryanodex, Eagle Pharmaceuticals) for rapid treatment of malignant hyperthermia (MH), along with the appropriate supportive measures.

MH is a potentially fatal inherited disorder triggered by exposure to certain drugs used for general anesthesia, including the neuromuscular blocking agent succinylcholine.

Ryanodex — which can be administered much more quickly than current formulations of dantrolene will be available in single-use vials containing 250 mg of dantrolene sodium in lyophilized powder form. It is formulated for rapid reconstitution and administration in less than 1 minute to patients in MH crisis. "Ryanodex should be administered by continuous rapid intravenous push beginning with a loading dose of 2.5 mg/kg, and continuing until symptoms subside."