Investigation of the Peripheral Analgesic Activity of Oxicams and Their Combinations with Caffeine

Objectives: Therapy of pain syndromes involves exposure to its source, receptors, and peripheral fibers. Treatment of acute pain and inflammation involves the use of nonsteroidal anti-inflammatory drugs and nonnarcotic analgesics. An alternative to obsolete analgesics is combined compositions. Experimental results clearly indicates that caffeine effectively enhances the peripheral analgesic activity when combined in an analgesic. The aim of the present study was to evaluate the peripheral analgesic activity of meloxicam, piroxicam, and their pharmacological combinations with caffeine. Materials and Methods: The peripheral analgesic activity of piroxicam, meloxicam, and their combinations with caffeine was studied using the abdominal writhing test. This method was used to induce pain of peripheral origin by intraperitoneal injection of 0.6% acetic acid solution. The investigated drugs, their combinations, and 3% starch mucilage were administrated 1 h before the introduction of the algogen. The cumulative number of writhing responses induced by acetic acid was determined over the subsequent 20 min. Results: All investigated drugs supplied a decrease in writhing in rats. Meloxicam and caffeine showed peripheral analgesic activity of 63.6% and 64.5%, respectively (p<0.05). The pharmaceutical combination of meloxicam and caffeine showed analgesic potential of 76.4%. Thus, caffeine potentiates the analgesic activity of meloxicam. The results exceeded the corresponding value of diclofenac sodium (67.3%). Conclusion: Experimental results clearly indicates that caffeine effectively enhances the peripheral analgesic action of meloxicam when combined in a pharmaceutical composition. These results can serve as a basis for the development of new domestic combined drugs.