Effectiveness and Adverse Events of Gabapentinoids as Analgesics for Patients with Burn Injuries: A Systematic Review with Meta-Analysis and Trial Sequential Analysis

(1) Background: Pain after a burn injury is difficult to endure, and emerging studies aim to ascertain the effects of gabapentin and pregabalin as non-opioid treatment options. (2) Methods: We searched for randomised controlled trials (RCTs) in six databases. The risk of bias was assessed using the RoB 2.0 tool. We performed meta-analysis and trial sequential analysis and used the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) methodology for judging the certainty of evidence (CoE). (3) Results: Five RCTs were included. Compared with placebo, gabapentinoids significantly decreased the pain intensity within 24 h (mean difference (MD) = −1.06, 95% confidence interval (CI): −1.47–−0.65) and from 72 h to 9 days (MD = −0.82, 95% CI: −1.16–−0.48), but not after 3 weeks (MD = −0.44, 95% CI: −1.31–0.42). Opioid consumption (mg/day) was reduced within 24 h (MD = −13.34, 95% CI: −22.16–−4.52) and from 72 h to 9 days (MD = −7.87, 95% CI: −14.82–−0.91). Increased risks of drowsiness (risk ratio (RR) = 3.255, 95% CI: 1.135–9.335) and dizziness (RR = 3.034, 95% CI: 1.006–9.147) were observed, but sensitivity analysis using the Bayesian method showed no increased risk. All endpoints were judged as low to very low CoE. (4) Conclusions: Gabapentinoids offer modest analgesic benefits as a component of multimodal pain management for burn injuries of less than 3 weeks. The adverse effects should be carefully monitored. Large-scale RCTs are warranted for the reinforcement of CoE in clinical use.