Muscular Pain
Skeletal muscle relaxants are used to relieve painful, chronic muscle spasm and spasticity associated with neural injury from diseases such as paraplegia, stroke, multiple sclerosis, and amyotrophic lateral sclerosis. In addition to physical therapy, consideration may be given to benzodiazepines, particularly diazepam, and baclofen.
Baclofen acts upon the GABA-receptor to inhibit the release of excitatory amino acids, especially at the spinal level, to decrease the spasm of skeletal muscles. It also helps relieve hiccups, possibly because of an effect on the diaphragm.
Diazepam is a long-acting benzodiazepine with GABA-potentiating effects in the CNS, again especially in the spinal cord. It has minimal autonomic effects and minimal locomotor effects at low doses.
For myofascial pain, injection of trigger points with a local anesthetic and a corticosteroid may be helpful.
Opioids are generally not helpful for the relief of muscle cramping.