Objective: To evaluate the anti- inflammatory effects of Gabapentin alone and as adjuvant with diclofenac by using formalin induced paw edema model.

Methods: After acclimatization of one week, adult winstar albino rats were divided into two groups: control and treatment (n=6). Treatment group received diclofenac (10 mg/kg), gabapentin (20 mg/kg), and gabapentin (20 mg/kg) + diclofenac (10 mg/kg) respectively. Paw edema was produced by injecting 0.2ml of 2% formalin subcutaneously on the dorsal surface of right hind paw. Animals received drug treatment 30 minutes before injection of formalin and paw volume was measured at 0, 30, 60, 120 and 240 minutes after formalin challenge with help of water plethysmometer.

Results: Both gabapentin alone and in combination with diclofenac caused a significant reduction (p< 0.01) in rat paw edema when compared to group given saline only. Reduction in paw edema with gabapentin and diclofenac was significantly superior when compared with either drug alone.

Conclusions: Combination of gabapentin and diclofenac showed synergistic anti-inflammatory
effect as compared to either drug alone or combination with diclofenac groups.

Keywords: Diclofenac, Gabapentin, Water Plethysmometer, Inflammation.

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Akhilesh Kumar

Junior Resident, Dept of Pharmacology, 4th Floor, Rims,

Ranchi, Bariatu, Jharkhand, Pin Code 834009 India

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