Respiratory depression reports with gabapentin versus pregabalin in the FDA Adverse Event Reporting System, 2024

Background. Gabapentin and pregabalin are often used alongside opioids, and the FDA has warned of serious breathing problems with both drugs. Objective. To compare reporting of respiratory depression for gabapentin versus pregabalin in the FDA Adverse Event Reporting System (FAERS), and to examine whether this differs when an opioid is also reported. Methods. Disproportionality analysis of FAERS reports from the four quarters of 2024 (1,480,549 reports after removing deleted cases and keeping the latest version of each case). Respiratory depression was defined as any of five MedDRA preferred terms. We calculated the proportional reporting ratio (PRR) and reporting odds ratio (ROR) with 95% confidence intervals, comparing each drug with reports listing neither drug and gabapentin directly with pregabalin, in all reports and by opioid status. A sensitivity analysis used a stricter three-term outcome. Results. Respiratory depression was reported in 123 of 5,268 gabapentin-only reports (2.3%), 85 of 6,516 pregabalin-only reports (1.3%) and 7,306 of 1,468,374 reports listing neither drug (0.50%). Compared with reports listing neither drug, the ROR was 4.78 (95% CI 3.99 to 5.73) for gabapentin and 2.64 (2.13 to 3.28) for pregabalin. For gabapentin versus pregabalin the ROR was 1.81 (1.37 to 2.39) in all reports, 2.10 (1.50 to 2.95) with an opioid reported and 2.00 (1.21 to 3.31) without. The sensitivity analysis gave 1.82 (1.35 to 2.46) in all reports. Conclusions. In 2024 FAERS reports, respiratory depression was reported disproportionately more often with gabapentin than with pregabalin. Estimates were similar with and without an opioid reported, with wider intervals in the no-opioid group. FAERS data cannot show causation or incidence. Code and results: https://github.com/rajnomani/faers-gabapentin-pregabalin