RYANODEX® is a vial containing 250 mg of dantrolene sodium in lyophilized powder form. It requires 5 mL of sterile water for reconstitution.9


RYANODEX® is a skeletal muscle relaxant drug indicated for9:

  • Treatment of malignant hyperthermia in conjunction with appropriate supportive measures
  • Prevention of malignant hyperthermia in patients at high risk

Precautions should be taken when administering RYANODEX® preoperatively for the prevention of malignant hyperthermia, including monitoring vital signs, avoiding known triggering agents, and monitoring for early clinical and metabolic signs of malignant hyperthermia that may indicate additional treatment is needed.

For full Prescribing Information please see the package insert.

Limitations of Other Brands for MH Treatment

  • Often, 12 or more vials need to be reconstituted for the loading dose (2.5mg/kg) for a 100 kg person, each containing 20 mg of dantrolene sodium6,7,12
  • Each vial requires reconstitution with 60 mL of sterile water6,7
  • Reconstitution time may be excessive in emergency situations (over 15 to 20 minutes)11
  • Amount of fluid administered (potentially over 700 mL) may cause physiological complications for the patient11

Eagle’s Answer

  • Significant reduction in time to reconstitute and administer product (less than a minute)9,10
  • Each vial contains 250 mg of dantrolene sodium that is reconstituted with 5 mL of sterile water9
  • Significant (150 fold) reduction in infusion fluid volume (5 mL per vial)9

RYANODEX® is currently marketed in the U.S. by Eagle Pharmaceuticals, Inc. To report product quality concerns or drug safety issues, including adverse events, please contact Eagle at: 1-855-318-2170.

Visit the RYANODEX® website.

Important Safety Information

RYANODEX® (dantrolene sodium) for injectable suspension is not a substitute for appropriate supportive measures in the treatment of malignant hyperthermia (MH), including discontinuing use of MH-triggering anesthetic agents, managing the metabolic acidosis, instituting cooling when necessary, and administering diuretics to prevent late kidney injury due to myoglobinuria (the amount of mannitol in RYANODEX® is insufficient to maintain diuresis).

RYANODEX® is associated with skeletal muscle weakness such as loss of grip strength and weakness in the legs, as well as drowsiness, dizziness, dysphagia, dyspnea, and decreased inspiratory capacity. Patients should not be permitted to ambulate without assistance until they have normal strength and balance. Care must be taken to prevent extravasation of RYANODEX® into the surrounding tissue due to the high pH of the reconstituted RYANODEX® suspension and potential for tissue necrosis.