There is insufficient evidence supporting improved efficacy of combination drug therapy vs monotherapy in the management of low back pain and sciatica, according to a systematic review published in the Journal of Pain.
Investigators conducted a systematic review of randomized trials in which patients with subacute or chronic nonspecific low back pain and sciatica were administered combination drug therapy, monotherapy, or placebo.
A total of 27 studies with individual sample sizes ranging from 22 to 805 participants (n=5942 patients) were selected. Of these, 20 studies assessed patients with low back pain only; 6 assessed patients with low back pain, with or without referred leg pain; and 1 study assessed patients with sciatica only. A total of 23 different drug combinations were compared with monotherapy and another 7 drug combinations were compared with placebo.
A total of 3 combination drug therapies indicated an analgesic effect in patients with acute or subacute low back pain with or without leg pain, but the observed effect was comparable to that obtained with monotherapy or placebo. In addition, these studies were deemed to provide low- (aceclofenac plus tizanidine vs aceclofenac; immediate term and nicoboxil plus nonivamide vs nicoboxil; short term) or moderate- (diclofenac plus B vitamins vs diclofenac; immediate term) quality evidence. In the review, 2 drug combinations were found to offer greater benefits vs a single drug in alleviating chronic low back pain, with or without leg pain (both of low quality): buprenorphine plus pregabalin vs buprenorphine (immediate term), and tramadol plus paracetamol vs placebo (short-term).
Adverse events occurred in all combination therapies at a higher risk compared with monotherapies and placebo (low-quality evidence). Of the 6 combination therapies that yielded serious adverse events, none carried a significantly greater risk than monotherapy or placebo.
“There is no clear evidence that combining drugs gives greater pain relief or reduces disability [better] than monotherapy or placebo in patients with low back pain and sciatica, despite most combinations not increasing the risk [for] side effects,” concluded the review authors.
Mathieson S, Kasch R, et al. Combination drug therapy for the management of low back pain and sciatica: Systematic review and meta-analysis. J Pain. 2019;20(1):1-15. doi:10.1016/j.jpain.2018.06.005