What medications are recommended for treating lower back pain?

Medications for Lower Back Pain

For acute low back pain, start with NSAIDs as first-line therapy; for chronic low back pain, use NSAIDs or tricyclic antidepressants; add skeletal muscle relaxants (cyclobenzaprine) for short-term use in acute cases only, and add gabapentin specifically when radicular pain is present. 1, 2

First-Line Pharmacological Treatment

Acute Low Back Pain (< 4 weeks)

• NSAIDs are the primary first-line medication, with good evidence showing moderate pain relief (10-20 points improvement on a 100-point visual analogue scale) and superior efficacy compared to placebo for global improvement 1
• Acetaminophen is a reasonable alternative if NSAIDs are contraindicated, though it provides slightly weaker analgesia (less than 10 points difference on a 100-point scale) but has a more favorable safety profile 1
• Use the lowest effective NSAID dose for the shortest duration necessary due to gastrointestinal, cardiovascular, and renal risks 1

Chronic Low Back Pain (> 12 weeks)

• NSAIDs remain effective for chronic pain with moderate short-term efficacy, though long-term safety data are limited 1, 2
• Tricyclic antidepressants (such as amitriptyline) provide small to moderate pain relief and are recommended as a first-line option for chronic low back pain 1, 2
• Duloxetine shows small improvements in pain intensity and function compared to placebo and is particularly useful when chronic pain coexists with depression 2

Second-Line and Adjunctive Medications

Skeletal Muscle Relaxants

• Use cyclobenzaprine only for acute low back pain (not chronic) for short-term relief (≤1-2 weeks maximum) 2
• Cyclobenzaprine has the strongest evidence among muscle relaxants, with pooled data from 20 trials showing superiority to placebo for short-term global improvement 2
• All muscle relaxants cause central nervous system adverse effects, primarily sedation, drowsiness, and dizziness 1, 3
• Critical pitfall: Do not prescribe muscle relaxants for chronic low back pain—no evidence supports efficacy beyond 2 weeks 2
• Start with 5 mg three times daily in elderly patients or those with hepatic impairment, as plasma concentrations are approximately double in these populations 3

Medications for Radicular Pain/Sciatica

• Gabapentin is specifically effective for the neuropathic component of radiculopathy, with small to moderate short-term benefits 1, 2, 4
• Titrate gabapentin to 1200-3600 mg/day, though evidence quality is inconsistent 2, 4
• Combine NSAIDs (for inflammatory component) with gabapentin (for neuropathic component) when radicular symptoms are present 2, 4
• Monitor for sedation, dizziness, and peripheral edema; adjust dosing in renal impairment 2

Opioid Analgesics and Tramadol

• Reserve opioids or tramadol for severe, disabling pain uncontrolled by acetaminophen and NSAIDs 1
• Use judiciously with time-limited courses due to risks of abuse, addiction, and aberrant drug-related behaviors 1
• Evidence shows only fair effectiveness for pain relief with substantial risks 1
• Reassess if no response occurs and consider alternative therapies or referral 1

Medications to Avoid

• Systemic corticosteroids are ineffective for low back pain with or without sciatica—good evidence shows no superiority over placebo 1, 2, 5
• Benzodiazepines have fair evidence for pain relief but carry significant risks of abuse, addiction, and tolerance; they are not FDA-approved for low back pain treatment 1, 2
• Baclofen is not recommended as a preferred muscle relaxant option—tizanidine has better evidence and safety profile 5
• Pregabalin shows no benefit for chronic nonradicular back pain and may worsen function 2

Treatment Algorithm by Clinical Scenario

Acute Nonspecific Low Back Pain

1. Start with NSAIDs (e.g., naproxen, ibuprofen) at lowest effective dose 1, 2
2. If NSAIDs contraindicated, use acetaminophen up to 4 g/day 1
3. If severe pain persists, add cyclobenzaprine 5-10 mg three times daily for ≤1-2 weeks 2, 3
4. Reserve opioids for severe, disabling pain unresponsive to above measures 1

Chronic Nonspecific Low Back Pain

1. Start with NSAIDs for moderate short-term efficacy 2
2. Add or substitute tricyclic antidepressants (amitriptyline) for small to moderate pain relief 1, 2
3. Consider duloxetine if depression coexists 2
4. Do not use muscle relaxants—no evidence beyond 2 weeks 2

Low Back Pain with Radiculopathy/Sciatica

1. Start with NSAIDs to target inflammatory component 2, 4
2. Add gabapentin (titrate to 1200-3600 mg/day) for neuropathic component 2, 4
3. May add cyclobenzaprine for short-term muscle spasm relief in acute presentations 4
4. Monitor and reassess; if no response, consider referral 1

Critical Safety Considerations

• NSAIDs increase cardiovascular risk (myocardial infarction, stroke) with longer use and higher doses; assess cardiovascular and gastrointestinal risk factors before prescribing 1, 2
• Consider proton-pump inhibitor co-administration in higher-risk patients on NSAIDs 1
• Acetaminophen at 4 g/day causes asymptomatic aminotransferase elevations even in healthy adults 1
• Muscle relaxants (tizanidine, chlorzoxazone) carry hepatotoxicity risks, usually reversible 1, 2
• Most medication trials were short-term (≤4 weeks); long-term safety data are sparse 1
• Combination therapy (e.g., cyclobenzaprine with naproxen) increases side effects, primarily drowsiness 3

Important Clinical Pitfalls

• Do not prescribe muscle relaxants for chronic low back pain—evidence only supports use up to 2 weeks for acute pain 2
• Do not use muscle relaxants in elderly patients without careful fall risk assessment due to sedation and cognitive impairment 2
• Do not expect muscle relaxants to work as monotherapy—combine with NSAIDs or acetaminophen and encourage remaining active 2
• Do not prescribe systemic corticosteroids—they are definitively ineffective 1, 2, 5
• Regularly reassess medication efficacy and adverse effects; extended courses should be reserved for patients showing clear continued benefits without major adverse events 4