dantrolene sodium hemiheptahydrate: clinical use

Prescribing considerations

• Initiate treatment when malignant hyperthermia is suspected without delaying or replacing established supportive measures.
• Assess calcium-channel blocker use, pre-existing hyperkalaemia, renal impairment and hearing-loss risk factors.
• Expect clinically significant skeletal muscle weakness and possible respiratory depression.
• Remain alert for recurrence of hypermetabolic features after initial resolution.

Contraindications and cautions

• Hypersensitivity to dantrolene sodium or any excipient.
• Avoid extravascular and intra-arterial administration because of tissue-necrosis and vascular-occlusion risks.
• Concomitant calcium-channel blocker use is not recommended.

Monitoring

• Track temperature, ventilation, acid-base status and other features of malignant hyperthermia.
• Monitor respiratory function and muscle weakness.
• Consider potassium and cardiac monitoring, particularly with hyperkalaemia risk or calcium-channel blocker exposure.
• Inspect venous access for leakage, inflammation or thrombosis.
• Consider renal function and hearing-risk factors because renal impairment may increase hydroxypropylbetadex exposure.

Clinical pharmacology

Dantrolene suppresses RYR1-mediated calcium release from skeletal-muscle sarcoplasmic reticulum. It is highly protein-bound, undergoes hepatic metabolism and is eliminated through renal and biliary routes.

Formulation and product differences

• This powder for intravenous solution contains hydroxypropylbetadex to improve solubility and reduce preparation fluid volume.
• The prepared solution is alkaline, must be free from visible particles and must not be mixed with other medicines or delivered through the same venous access.
• The reconstituted solution requires protection from light and must not be refrigerated.

Injection

Route: Parenteral

Strengths: 120 mg