What is the best medication for treating muscle spasms?

Best Medications for Muscle Spasm

For muscle spasm, baclofen is the preferred medication when true muscle spasm is suspected, while cyclobenzaprine 5mg TID is recommended for musculoskeletal pain with associated muscle tension. 1

First-line Options

Muscle Relaxants

• Muscle relaxant drugs (cyclobenzaprine, carisoprodol, chlorzoxazone, methocarbamol) may relieve skeletal muscle pain, but their effects are nonspecific and not actually related to muscle relaxation 1
• These medications should not be prescribed in the mistaken belief that they directly relieve muscle spasm, as they may inhibit polysynaptic myogenic reflexes in animal models, but the relationship to pain relief remains unknown 1
• If true muscle spasm is suspected as the root cause of pain, consider medications with known effects on muscle spasm (baclofen, benzodiazepines) 1

Cyclobenzaprine

• Cyclobenzaprine is essentially identical to amitriptyline with similar potential adverse effects 1
• FDA-approved clinical studies show cyclobenzaprine is effective in improving muscle spasm, reducing local pain and tenderness, and increasing range of motion in acute, painful musculoskeletal conditions 2
• Lower dose (5 mg TID) is as effective as higher dose (10 mg TID) with less sedation 3
• Cyclobenzaprine has been evaluated in the most clinical trials for musculoskeletal conditions and has consistently been found effective compared to placebo 4
• Extended-release formulation (15 mg once daily) can be effective with potentially fewer daytime drowsiness issues 5

Baclofen

• Baclofen is an agonist of gamma-aminobutyric acid type B 1
• Documented efficacy as a second-line drug for paroxysmal neuropathic pain 1
• Used in patients with severe spasticity resulting from central nervous system injury, demyelinating conditions, and other neuromuscular disorders 1
• Start with a low dose and gradually increase to minimize common side effects of dizziness, somnolence, and gastrointestinal symptoms 1
• Discontinuation after prolonged use requires slow tapering to prevent withdrawal symptoms 1

Alternative Options

Benzodiazepines

• Limited efficacy in the management of persistent pain 1
• Current information does not support a direct analgesic effect 1
• May be justified for a trial in relief of muscle spasm, especially when anxiety, muscle spasm, and pain coexist 1
• High risk profile in older adults usually outweighs potential benefits 1

Tizanidine

• Effective compared to placebo for musculoskeletal conditions (primarily acute back or neck pain) 4
• Has been found efficacious for acute low back pain in multiple trials 1
• Similar overall rate of adverse effects compared to baclofen, but associated with more dry mouth while baclofen causes more weakness 4

Special Considerations

Older Adults

• Clinicians should be aware that many muscle relaxants may be associated with greater risk for falls in older persons 1
• In geriatric patients, cyclobenzaprine shows higher plasma concentrations, with elderly males having approximately 2.4-fold higher levels compared to younger males 2
• The high risk profile of benzodiazepines in older adults usually obviates any potential benefit 1

Liver Disease

• Cyclobenzaprine should be used with caution in subjects with mild hepatic impairment, starting with the 5 mg dose and titrating slowly upward 2
• Use of cyclobenzaprine in subjects with moderate to severe hepatic impairment is not recommended 2
• Dantrolene has been associated with rare serious hepatotoxicity 4

Treatment Algorithm

1. For true muscle spasm (spasticity) from neurological conditions:

   • Start with baclofen at low dose (10 mg/day), with weekly increase of 10 mg/day up to 30 mg/day 1
   • Monitor for dizziness, somnolence, and gastrointestinal symptoms 1

2. For musculoskeletal pain with associated muscle tension:

   • Begin with cyclobenzaprine 5 mg TID for 7-14 days 3, 6
   • Extended-release cyclobenzaprine 15 mg once daily is an alternative with potentially less daytime drowsiness 5
   • Combination therapy with NSAIDs has not shown superior efficacy compared to cyclobenzaprine alone 6

3. For patients with contraindications to first-line agents:

   • Consider tizanidine as an alternative, particularly for acute back or neck pain 1, 4
   • Methocarbamol may be considered for muscle cramps in specific populations like cirrhosis patients 1

Common Pitfalls and Caveats

• Carisoprodol has been removed from the European market due to concerns about drug abuse and should be avoided 1, 7
• Do not prescribe muscle relaxants in the mistaken belief that they directly relieve muscle spasm 1
• Discontinuation of baclofen after prolonged use requires careful management with slow tapering to prevent withdrawal symptoms 1
• Sedation is the most common adverse event with cyclobenzaprine, particularly at higher doses 3
• Combination therapy with cyclobenzaprine plus ibuprofen has not shown superiority to cyclobenzaprine alone 6