323 patients with acute low back pain were randomized to receive naproxen with 1 of 3 concurrent medications: cyclobenzaprine, oxycodone/acetaminophen, or a placebo. The purpose of the study was to compare the efficacy of these treatments and determine if the addition of these skeletal muscle relaxants and opioids to naproxen treatment provided further benefits to the patient. Improvement to RMDQ disability score was similar between all 3 groups up to 3 months after the start of treatment, but the risk of adverse events was higher in patients receiving cyclobenzaprine or oxycodone/acetaminophen compared to those receiving placebo. No other differences were observed between treatment groups.