Dantrolene is an FDA-approved drug indicated for chronic use for spasticity (1.6–6.5 mg/kg/day38) and acutely for malignant hyperthermia (4–8 mg/kg38) and has been widely studied in multiple animal models and humans.46, 47, 48, 49, 50 It targets the RyR1, which is responsible for Ca2+ release from the sarcoplasmic reticulum (SR) and regulating levels of cytosolic and SR luminal Ca2+ levels essential for excitation-contraction coupling. Here, RYR1 is linked to Spasticity.