A systematic review «Soliman N, Moisset X, Ferraro MC, ym. Pharmacother...»1 measured effectiveness of SNRI medications on neuropathic pain, including 14 randomized trials. A reanalysis of these trials suggested a mean 0.76 points decrease (95% CI -0.98 to -0.55) in average pain at 3-9 weeks follow up, translating to about 18 % decrease in pain (95% CI -23 % to -13 %).
The same systematic review found RD of 7.2 % (5.3 % to 9.2 %) for withdrawals due to side effects. We were unable to find direct evidence of specific adverse events. However, for patients with fibromyalgia, a Cochrane review «Welsch P, Üçeyler N, Klose P, ym. Serotonin and no...»2 suggested an increase in risk of nausea (RD 16%), somnolence (RD 5%), and insomnia (RD 3%).
The quality of evidence was downgraded due to high risk of bias.
| Reference | Study type | Population | Intervention and comparison | Outcomes | Risk of bias |
|---|---|---|---|---|---|
| RCT=randomized controlled trial; SR=systematic review; MA=meta-analysis | |||||
| «Soliman N, Moisset X, Ferraro MC, ym. Pharmacother...»1 | SR/MA | Adult patients with neuropathic pain | SNRI medications vs placebo | Decrease in average pain | High |
| Reference | Comments |
|---|---|
| «Soliman N, Moisset X, Ferraro MC, ym. Pharmacother...»1 | Most trials were at high risk of bias, mainly due to high drop out rates. |
Results
| Reference | Number of studies and number of patients (I/C) | Follow-up time | Mean (SD) I | Mean (SD) C | Mean difference (95% CI) |
|---|---|---|---|---|---|
| Level of evidence: Moderate The quality of evidence was downgraded due to high risk of bias. *We calculated the effect size by using the data provided by the systematic review. We used random effects meta-analysis. We excluded 2 trials included in the original review due to insufficient data (total 102 patients). I= intervention; C=comparison; CI=confidence interval |
|||||
| [R1] | 12 trials, 2699 patients | 4-14 weeks | Not reported | 4.21 | -0.76 (-0.98 to -0.55)* Relative effect: -18 % (-23 % to -13 %) |