Antinociceptive Effect of Racemic Flurbiprofen and Caffeine Co-Administration in an Arthritic Gout-Type Pain in Rats

Preclinical Research Drug combinations are routinely used in the treatment of pain. In drug associations, adjuvants such as caffeine, are employed with different non‐steroidal anti‐inflammatories drugs (NSAIDs), however, at present does not exist studies showing the effect of the combination of racemic flurbiprofen (rac‐Flur) in association with caffeine. The objective of this work was to evaluate the combination of rac‐Flur + caffeine oral in arthritic gout‐type pain in rats. The antinociceptive effects of the rac‐Flur alone and in combination with caffeine were analyzed on a pain‐induced functional impairment model in rat. rac‐Flur induced a dose‐dependent antinociceptive effect and caffeine did not present any effect. The combination of rac‐Flur and caffeine achieve a higher percentage of antinociceptive effect compared with the individual administration of rac‐Flur. The dose‐response curve (DRCs) shows that the combination of rac‐Flur (31.6 mg/kg) + caffeine (17.8 mg/kg) exhibited the maximal antinociceptive efficacy (294.0 ± 21.2 area units), while rac‐Flur alone (31.6 mg/kg) showed 207.2 ± 35.2 au, thus indicating an increase in efficacy (potentiation). Furthermore, the DRCs of the combinations presented a displacement to the left, indicating a change in the potency. Caffeine is able to increase the effect of rac‐Flur in the arthritic gout‐type pain in rats. Drug Dev Res 77 : 192–198, 2016. © 2016 Wiley Periodicals, Inc.