Analgesic and Anti-Inflammatory Effects of Diclofenac and Ketoprofen Patches in Two Different Rat Models of Acute Inflammation

Objectives: Topical forms of Non-steroidal anti-inflammatory drugs (NSAIDs) used to treat pain, fever and inflammation ensure reduced occurrence of systemic adverse effects that are common with oral application. Compared to the systemic therapy, topical applications of NSAIDs require lower doses to achieve pain relief, and thus pose lower risk of major drug interactions. We aimed to evaluate analgesic and anti-inflammatory effects of diclofenac and ketoprofen patch in the rat model of acute inflammation.Methods: Wistar male rats, body weight 220-290 g were randomized into five groups with six rats. Two groups were treated with diclofenac patch at different doses, two with ketoprofen patch at different doses, while a placebo patch was administered to the control group. After patches removal and initial measurements of pain, gait, body temperature, paw temperature, color and paw volume, the models of acute inflammation were applied: yeast-induced hyperalgesia and carrageenan-induced edema. Measurements were repeated one, three and five hours after inflammation induction.Results: Acute inflammations induced by both used models did not affect the whole-body temperature. However, there were significant (p < 0.05) differences in pain, gait, paw temperature, color and volume between low and high dose diclofenac and ketoprofen groups compared to the control group in different time points, in both models.Conclusions: Our results confirm the analgesic and anti-inflammatory efficacy of diclofenac and ketoprofen patches when used in two well-established rat models of inflammation. These findings suggests that diclofenac patch would be a useful formulation in clinical practice as a novel treatment option. However, new prospective double blind randomized clinical trials are necessary to evaluate analgesic and antiinflammatory effect of topically applied NSAIDs when used in specific pain and inflammation indications.& COPY; 2022 The Author(s). Published by Elsevier B.V. on behalf of King Saud University. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).