Acetaminophen Isn't Effective for Acute Low-Back Pain

Acetaminophen and nonsteroidal anti-inflammatory drugs have similar analgesic effects in patients with acute low-back pain; consensus guidelines recommend either of these medications as first-line analgesia (NEJM JW Gen Med Oct 25 2007). But acetaminophen and placebo have not been compared head-to-head for this indication.

Researchers randomized 1652 Australian patients with recent-onset low-back pain who were seen at primary care centers to receive as long as 4 weeks of treatment with one of three blinded treatment regimens:

• Thrice-daily modified-release acetaminophen (2 665-mg tablets) plus placebo (≤8 tablets daily, as needed)

• Thrice-daily placebo (2 tablets) plus immediate-release acetaminophen (≤8 500-mg tablets daily, as needed)

• Double pl…