Gabapentin is widely used for epilepsy and neuropathic pain. Beyond neurological indications, preclinical evidence suggests that gabapentin may exert anti-inflammatory effects that have not been systematically reviewed. A systematic review (2015–2025) was performed, resulting in thirteen in vitro and in vivo studies evaluating gabapentin’s impact on inflammatory signaling pathways, cytokine production, immune cell activity, and tissue inflammation. Outcomes included molecular pathways, inflammatory mediators, histopathological changes, and functional inflammatory measures. Risk of bias and study quality were assessed using the SYRCLE RoB tool for in vivo studies and the SciRAP approach for in vitro studies. Gabapentin demonstrated potential modulation of inflammatory responses in neuropathic pain, neuroinflammation, uveitis, and sepsis models through inhibition of MAPK and NF-κB signaling, reduction in pro-inflammatory cytokines, modulation of PPAR signaling pathways, and activation of Nrf2/HO-1 pathway. Gabapentin’s pharmacological actions extend beyond neuronal excitability to include modulation of inflammatory pathways, supporting a broader biological role for gabapentin. Although preclinical data support gabapentin’s potential anti-inflammatory properties, further targeted experimental and clinical studies are warranted to confirm these findings.