Hamadan University of Medical Sciences Avicenna Journal of Clinical Microbiology and Infection 2383-0298 13 3 2026 09 29 Anti-Inflammatory Effects of Ivermectin in Carrageenan-Induced Paw Edema in Rats 159 166 10.34172/ajcmi.3750 EN Farhang Mehrnia Erfan Norouzifard Hamid Soraya https://orcid.org/0000-0003-0602-230X Journal Article 10.34172/ajcmi.3750 2025 08 10 2026 07 05 Introduction: Ivermectin has shown potential anti-inflammatory properties in some studies, although the results are conflicting. Therefore, this study investigated the anti-inflammatory effects of ivermectin in rats using the carrageenan-induced paw edema model. Methods: Thirty male Wistar rats were randomly assigned to carrageenan, dimethyl sulfoxide, and indomethacin groups and two ivermectin-treated (at 0.2 mg/kg and 10 mg/kg doses) groups (n=6 each). Paw edema was induced by the subcutaneous injection of carrageenan, and ivermectin was intraperitoneally injected at doses of 0.2 mg/kg and 10 mg/kg. Then, paw thickness was hourly measured for 5 hours. Finally, myeloperoxidase (MPO) activity, malondialdehyde (MDA) levels, and histopathological changes in paw tissues underwent assessment. Results: At the second hour post-carrageenan injection, ivermectin at 0.2 mg/kg (P<0.01) reduced inflamed paw thickness. At the third hour, ivermectin at 0.2 mg/kg (P<0.001) and 10 mg/kg (P<0.01) also decreased inflamed paw thickness. Likewise, both doses of ivermectin (P<0.01) contributed to a similar extent to diminishing inflammation at the fourth hour. Moreover, ivermectin at doses of 0.2 mg/kg and 10 mg/kg could reduce MPO activity (P<0.01) and MDA levels (P<0.01), respectively. Ultimately, histopathological evaluation revealed a dose-dependent decline in leukocyte infiltration and inflammation in ivermectin-treated rats. Conclusion: Ivermectin demonstrated anti-inflammatory activity by decreasing paw edema, oxidative stress, neutrophil activity, and leukocyte infiltration, suggesting its potential as an anti-inflammatory agent.