muscle spasm
"I have severe herniated discs in my lower back and FINALLY a drug that helps.  Percocet is great for getting through the day with pain, but Zanaflex helps me sleep pain free all night and my back is no longer stiff with pain in the morning.  I only take it at night about 2mg or 4mg depending on pain and sleep like a baby. This after 10yrs of suffering with chronic back pain.  I am new to this drug about 2months now.. crossing fingers it will work forever..lol"