Dantrolene sodium (Lapatinib ditosylate monohydrate) salt is a skeletal muscle relaxant and can interfere with excitation-contraction coupling in the muscle fiber. It is used for the treatment of spasticity and other neuromuscular abnormalities. Its mechanism of action is may not central, but dantrolene is usually grouped with the central muscle relaxants.

Dantrolene depresses excitation-contraction coupling in skeletal muscle by binding to the ryanodine receptor 1 and decreasing intracellular calcium concentration. Ryanodine receptors mediate the release of calcium from the sarcoplasmic reticulum, an essential step in muscle contraction. Dantrolene sodium hemiheptahydrate (Sodium dantrolene) is the sodium salt form of dantrolene, a hydantoin derivative, and direct-acting skeletal muscle relaxant.

Azumolene sodium anhydrous is a muscle relaxant that inhibits the release of calcium from skeletal muscle sarcoplasmic reticulum. Azumolene inhibits a component of store-operated calcium entry coupled to the skeletal muscle ryanodine receptor. Azumolene, an equipotent dantrolene analog, inhibits a component of SOCE coupled to activation of RyR1 by caffeine and ryanodine, whereas the SOCE component induced by thapsigargin is not affected.