What other medications can be used to treat myofascial pain syndrome?

Medications for Myofascial Pain Syndrome

For myofascial pain syndrome (MPS), use topical analgesics (lidocaine patches or diclofenac patches) as first-line pharmacotherapy, combined with trigger point injections using local anesthetic, while avoiding muscle relaxants, NSAIDs, and opioids due to insufficient or inconclusive evidence.

Evidence-Based Pharmacologic Approach

First-Line: Topical Agents

Topical lidocaine patches (5%) are the most strongly supported medication for MPS 1, 2. Apply daily to painful trigger point areas with minimal systemic absorption 3. Lidocaine patches deliver medication gradually over hours and are more effective than creams or ointments for localized pain 4.

Topical diclofenac (gel applied 3 times daily or 180 mg patch once or twice daily) also has evidence for localized musculoskeletal pain 3, 2.

For refractory cases, consider topical amitriptyline 1-2% compounded with ketamine 0.5-5% applied up to 3 times daily to affected areas 4. This combination blocks sodium channels and NMDA receptors in peripheral nociceptive terminals.

Second-Line: Antidepressants (If Neuropathic Component Present)

If MPS has a neuropathic pain component or coexists with chronic pain conditions:

• Duloxetine: Start 30-60 mg daily, increase to 60-120 mg daily 3, 5
• Tricyclic antidepressants (secondary amines preferred): Nortriptyline or desipramine 10-25 mg nightly, increase to 50-150 mg nightly 3, 5

These work through monoaminergic neurotransmission enhancement, not muscle relaxation 6. Avoid tertiary amines (amitriptyline, imipramine) in older adults due to anticholinergic effects 5.

Medications with Insufficient Evidence

Do NOT routinely use 1:

• NSAIDs (oral): Insufficient evidence for MPS specifically
• Muscle relaxants (cyclobenzaprine, methocarbamol, carisoprodol): No evidence for chronic pain, do not actually relax muscle, and carry fall risk 7, 6, 7
• Opioids: Inconclusive evidence and high adverse effect profile 1
• Gabapentin/pregabalin: Inconclusive evidence for MPS (effective for neuropathic pain but MPS is musculoskeletal) 1
• Botulinum toxin: Insufficient evidence 1

Critical Caveats

Muscle relaxants are a common pitfall: Despite their name and widespread use, they do not directly relax skeletal muscle and lack evidence for chronic musculoskeletal pain 7. They work through nonspecific central effects and carry significant adverse effects in older adults, including sedation and falls 8.

Benzodiazepines have no role: They lack direct analgesic effects and carry high risk in older adults 8, 9.

Capsaicin is not helpful: Despite theoretical benefit, clinical experience shows capsaicin is not effective for most MPS patients 4.

Practical Algorithm

1. Start with topical lidocaine 5% patches to trigger point areas daily
2. Add trigger point injections with local anesthetic (most effective intervention) 1, 10, 11
3. If inadequate response after 2-4 weeks, add topical diclofenac patch
4. If neuropathic features present (burning, shooting pain), add duloxetine or nortriptyline
5. For refractory cases, trial compounded topical amitriptyline-ketamine
6. Avoid oral NSAIDs, muscle relaxants, and opioids - insufficient evidence and significant adverse effects

The most recent high-quality evidence 1 from 2025 confirms that local anesthetic injections have sufficient evidence, while most oral medications lack support for MPS specifically. Focus pharmacotherapy on topical agents while addressing underlying postural, ergonomic, and behavioral factors 10, 11.