Tizanidine
Tizanidine is a fast-acting drug used for the management of muscle spasm, which may result from the effects of multiple sclerosis, stroke, an acquired brain injury, or a spinal cord injury.  It may also be caused by musculoskeletal injury.  Regardless of the cause, muscle spasticity can be an extremely painful and debilitating condition.   Initially approved by the FDA in 1996, tizanidine is an Alpha-2 adrenergic receptor agonist reducing spasticity by the presynaptic inhibition of excitatory neurotransmitters that cause firing of neurons promoting muscle spasm.