Drug

Pharmacology Table 3: Skeletal Muscle Relaxants
Usual Dose1,2,3,4,5
Monthly Cost6*
Comments 1,2,3,4, 5
Antispasmodics-Nonbenzodiazepine
Metabolized to meprobamate, an addictive sedative-hypnotic agent. Concern over abuse and dependence. Controlled substance in some states. Recommend to avoid. Evidence does not support use beyond 2-3 weeks. Withdrawal symptoms may occur with Rare hepatotoxicity. May discolor urine orange or red.
5mg dose associated with lower incidence of somnolence with efficacy similar to 10mg dose. TCA derivative-contraindicated in patients with cardiac conduction abnormalities. Should not be used within 14 days of MAOIs. Anticholinergic side effects. Avoid in elderly. Multiple drug-drug interactions (CYP3A4, 1A2, 2D6 substrate).
Associated with hypersensitivity reaction. Use with caution in mild-mod hepatic disease. Avoid use in severe renal or hepatic dysfunction. Less CNS side effects, lack of abuse potential, and limited accumulation due to short half-life. Use with caution in renal and hepatic disease and in patients with history of seizure disorder. May discolor urine brown-black or Anticholinergic side effects-not recommended in elderly. Do not discontinue abruptly.
Antispasticity
Use with caution in renal dysfunction and in patients with history of seizure disorder. Do not discontinue abruptly.
Limited CNS effects. Black-box warning about dose-related fatal or nonfatal hepatitis; avoid in hepatic disease. Discontinue if no Antispasmodic and Antispasticity
Potential for abuse. Avoid in elderly and patients with renal or hepatic impairment. Multiple drug-drug interactions (CYP3A4, 2C19).
May have gastroprotective effects. Frequent liver function monitoring recommended (may cause hepatotoxicity). May cause hypotension and bradycardia. Adjust dose in renal insufficiency. Avoid concomitant use with ciprofloxacin and fluvoxamine, use caution with other CYP1A2 inhibitors.
*Cost based on generic when available for maximum daily dose. $: <$20; $$: $20-$50; $$$: $50-$100; $$$$: >$100 References
Max MB, Gilron IH. “Antidepressants, Muscle Relaxants, and N-Methyl-D-Aspartate Receptor Antagonists.” in Bonica’s Management of Pain, 3 rd ed. Loeser JD, Butler SH, Chapman CR, Turk DC. Eds. Lippincott, Williams, Wilkins: Philadelphia; 2001: 1710-1726.
Toth PP, Urtis J. Commonly used muscle relaxant therapies for acute low back pain: a review of carisoprodol, cyclobenzaprine hydrochloride, and metaxalone. Clin Ther. 2004; 26: 1355-1367.
van Tulder MW, Touray T, Furlan AD, Solway S, Bouter LM. Muscle relaxants for nonspecific low back pain: a systematic review within the framework of the Cochrane Collaboration. Spine Lexi-Comp (Lexi-Drugs, Comp + Specialties) [computer program]. Lexi-comp; May 29, 2009.
See S, Ginzburg R. Skeletal muscle relaxants. Pharmacotherapy 2008;28:207-213.
Do not redistribute. No derivative works are to be made.

Source: http://www.paineducation.vcu.edu/documents/PharmTable03.pdf