Mechanism of action of dantrolene sodiumdantrolene is s skeletal muscle relaxant which differs from the classical neuromuscular blocking drugs. it inhibits the release of calcium from sarcoplasmic reticulam and suppresses excitation contraction coupling. it reduces the calcium level associated with malignant hyperthermia crises.indications for dantrolene sodium1. spasticity resulting from upper motor neuron lesions such as spinal cord injury, stroke, multiple sclerosis, cerebral palsytypical dosage for dantrolene sodiumoral adult: 25mg/day if needed dose can be increased by 25mg every 4 - 7 days up to 400mg/day in 4 divided doses. children above 5 years: 0.5mg/kg 2 times daily, if needed dose can be gradually increased by 0.5mg/kg up to 3mg/kg 2 - 4 times daily. maximum dose: 400 mg/day