Nonspecific low back pain: assessment of available medications

Many medications have been evaluated for the treatment of nonspecific low back pain. The only medications proven to be more effective than a placebo in chronic low back pain are nonsteroidal antiinflammatory drugs (NSAIDs), the acetaminophen-tramadol combination, antidepressants other than selective serotonin reuptake inhibitors, and some types of spinal applications of glucocorticoids or local anesthetics. However, the efficacy of these drugs in inducing pain relief is limited, and NSAIDs are the only drugs that also improve function. Nevertheless, the outcome of nonspecific low back pain is favorable in most cases, even in placebo-treated patients. In addition, treatment effects vary dramatically across studies. One factor in this variability is the heterogeneity of patient populations. To improve the uniformity of patient populations enrolled in therapeutic trials, the selection criteria should take into account the nociceptive, dysfunctional, and possible neuropathic components of the pain syndrome.