Is pregabalin (an anticonvulsant) effective for treating shoulder pain?

Pregabalin for Shoulder Pain

Pregabalin is not recommended as a first-line treatment for shoulder pain, as there is insufficient evidence supporting its efficacy for musculoskeletal shoulder pain, and it should only be considered if the shoulder pain has a clear neuropathic component (such as hemiplegic shoulder pain after stroke or nerve injury).

Evidence for Pregabalin in Shoulder Pain

Musculoskeletal Shoulder Pain

• No established role: Current guidelines do not support pregabalin for typical musculoskeletal shoulder pain conditions like rotator cuff tendinopathy, adhesive capsulitis, or osteoarthritis of the shoulder 1.
• Pregabalin is FDA-approved specifically for neuropathic pain conditions (diabetic peripheral neuropathy, postherpetic neuralgia, and fibromyalgia), not for musculoskeletal pain 1, 2.
• For osteoarthritis pain (which can affect the shoulder), NSAIDs and duloxetine are recommended first-line pharmacologic options, not pregabalin 1.

Post-Stroke Hemiplegic Shoulder Pain

• Limited evidence of benefit: One small study (70 participants) showed that pregabalin 100 mg twice daily combined with therapeutic ultrasound reduced pain more than ultrasound alone in post-stroke shoulder pain, with VAS scores improving to 21.32 versus 41 at two weeks 3.
• However, stroke rehabilitation guidelines recommend suprascapular nerve block as an adjunctive treatment for hemiplegic shoulder pain (Class IIb, Level B evidence), but do not specifically recommend pregabalin for this indication 1.
• For central poststroke pain (which can include shoulder region pain), pregabalin is considered only as a second-line treatment after amitriptyline and lamotrigine, with mixed clinical trial results showing no significant improvement over placebo for daily pain reporting 1.

When Pregabalin Might Be Considered

Neuropathic Component Required

• Pregabalin should only be considered if shoulder pain has clear neuropathic features: burning, shooting, or electric-shock quality pain; allodynia (pain from non-painful stimuli); or documented nerve injury 1.
• Conditions where this might apply include cervical radiculopathy with shoulder radiation, brachial plexopathy, or post-stroke central pain affecting the shoulder region 1.

Dosing If Used

• Starting dose: 50 mg three times daily or 75 mg twice daily 4, 5, 2.
• Titration: Increase to 300 mg/day after 3-7 days if tolerated; maximum 600 mg/day divided into 2-3 doses 4, 5.
• Assessment period: Allow 4 weeks to fully evaluate efficacy before abandoning treatment 5.
• Renal adjustment required: Pregabalin is renally excreted and requires dose reduction in renal impairment 4.

Expected Adverse Effects

• Common side effects (dose-dependent): dizziness (23-46%), somnolence (15-25%), peripheral edema (10%), dry mouth, and constipation 4, 2, 6.
• Discontinuation rates: 18-28% of patients stop treatment due to adverse events 6.
• Fall risk: Particularly concerning in elderly patients due to dizziness and somnolence 4.

Recommended Approach for Shoulder Pain

First-Line Treatments

• Non-pharmacologic interventions: Physical therapy, therapeutic exercise, and manual therapy should be prioritized 1.
• Pharmacologic options for musculoskeletal shoulder pain: Topical or oral NSAIDs (at lowest effective dose and shortest duration) 1.
• For inflammatory conditions: Consider corticosteroid injection for subacromial bursitis or glenohumeral joint inflammation 1.

When to Consider Pregabalin

• Only after: Establishing that pain has neuropathic characteristics through clinical examination (allodynia, hyperalgesia, dermatomal distribution) 1.
• Only after: First-line neuropathic pain treatments have been tried or are contraindicated (tricyclic antidepressants like amitriptyline, or SNRIs like duloxetine) 1.
• Document: Specific neuropathic pain features and functional goals before initiating treatment 1.

Critical Pitfalls to Avoid

• Do not use pregabalin for routine musculoskeletal shoulder pain: The evidence supports its use only in neuropathic pain conditions, and using it for non-neuropathic pain exposes patients to significant side effects without proven benefit 1, 6.
• Do not start at high doses: Begin with 50-75 mg doses to minimize dizziness and somnolence, particularly in elderly patients 4, 5.
• Do not continue indefinitely without reassessment: If no meaningful improvement occurs after 4 weeks at adequate doses (300-600 mg/day), discontinue the medication 5.
• Screen for fall risk: Pregabalin significantly increases dizziness and should be used cautiously in patients at risk for falls 4.