Dantrolene sodium

Химические свойства

Orange Powder

Использование

Dantrolene Sodium Salt Hemiheptahydrate is a muscle relaxant (skeletal). Used in the treatment of malignant hyperthermia.

Определение

ChEBI: A hydrate which is the hemiheptahydrate of anhydrous dantrolene sodium.

Биологические функции

Dantrolene sodium (Dantrium) is used in the treatment of spasticity due to stroke, spinal injury, multiple sclerosis, or cerebral palsy. It is also the drug of choice in prophylaxis or treatment of malignant hyperthermia.
Susceptibility to malignant hyperthermia is due to a rare genetic defect that allows Ca⁺⁺ release from the sarcoplasmic reticulum to open more easily and close less readily than normal. This leads to a high level of Ca⁺⁺ in the sarcoplasm, which produces muscle rigidity, oxygen consumption, and heat. Dantrolene acts by blocking Ca⁺⁺ release from the sarcoplasmic reticulum and uncoupling excitation from contraction.
Dantrolene is active orally, although its absorption is slow and incomplete. Its biological half-life (t_1/2) is 8.7 hours in adults. The drug is metabolized by liver microsomal enzymes and is eliminated in the urine and bile. It is given IV when treating an attack of malignant hyperthermia. The most prominent and often limiting feature of dantrolene administration is dose-dependent muscle weakness. Other side effects are drowsiness, dizziness, malaise, fatigue, and diarrhea. Symptomatic hepatitis is reported in 0.5% of patients receiving it and fatal hepatitis in up to 0.2%. Contraindications include respiratory muscle weakness and liver disease. It is suggested that patients on dantrolene therapy be given regular liver function tests.