What medication would you prescribe for an adult with non‑specific low back pain persisting for three months?

Medication for 3-Month Low Back Pain

For an adult with non-specific low back pain lasting 3 months (chronic), prescribe NSAIDs as first-line pharmacologic therapy, with duloxetine as an alternative if NSAIDs are contraindicated or ineffective.

First-Line Pharmacologic Treatment

NSAIDs are the initial medication of choice for chronic low back pain. 1, 2 The American College of Physicians systematic review found that NSAIDs provide small to moderate pain relief for chronic low back pain, though benefits are smaller than previously observed. 1 Recent guidelines consistently recommend NSAIDs as first-line pharmacotherapy across multiple countries. 3

Important Caveats for NSAIDs:

• Use cautiously in patients at higher risk for gastrointestinal bleeding, cardiovascular disease, or renal impairment 4
• Effects are generally short-term with modest improvements in function 1
• The pain relief is small to moderate, not dramatic 1

Second-Line Pharmacologic Option

Duloxetine (an SNRI) is the evidence-based alternative when NSAIDs fail or are contraindicated. 1, 2 The ACP systematic review specifically identified duloxetine as effective for chronic low back pain with modest effects. 1 More recent evidence confirms SNRIs probably have a small effect on pain intensity (mean difference -5.25 on 0-100 scale) and trivial effects on disability. 5

Duloxetine Considerations:

• Provides small but measurable pain reduction 5
• Probably increases risk of adverse events (RR 1.17) 5
• May be particularly useful if comorbid depression exists 6

Medications to Avoid or Use with Extreme Caution

Acetaminophen should NOT be prescribed - new evidence demonstrates it is ineffective for low back pain. 1, 4

Opioids should be avoided - evidence is limited to short-term trials showing only modest effects, with established serious harm profiles that were not adequately assessed in trials. 1 Guidelines universally recommend opioids only as last resort. 7

Muscle relaxants are ineffective for chronic low back pain - they work only for acute pain (<4 weeks) and cause sedation. 1, 4

Benzodiazepines are ineffective - evidence shows no benefit for low back pain. 1

Systemic corticosteroids do not appear effective. 1

Tricyclic antidepressants (TCAs) probably have little to no effect on pain intensity but may have small effects on disability. 5 Evidence is insufficient to recommend them routinely. 1

Critical Clinical Approach

Nonpharmacologic treatment should be first-line management before or concurrent with any medication. 2 This includes exercise therapy, spinal manipulation, physical therapy, and patient education. 2, 3

The shift in modern guidelines is away from pharmacotherapy due to limited efficacy and adverse effect risks. 7 Medications provide only small to moderate, primarily short-term effects on pain with generally smaller improvements in function. 1

Common Pitfalls

• Prescribing acetaminophen based on outdated guidelines - it doesn't work 1
• Starting opioids too readily - risks outweigh minimal benefits 1, 7
• Expecting dramatic pain relief from any medication - effects are modest at best 1
• Ignoring nonpharmacologic approaches which should be primary treatment 2, 7