Synergistic effects of anethole and ibuprofen in acute inflammatory response.

This study assessed the effect of the combination of anethole and ibuprofen in comparison with monotherapy by either drug alone, using two in vivo inflammatory models, namely the pleurisy and paw edema in rats. We also measured the levels of the TNF protein in plasma, and the ability of anethole to inhibit, in vitro, the activity of the cyclooxygenase 1 and cyclooxygenase 2 enzymes. The test drugs (anethole; ibuprofen; anethole + ibuprofen), at different doses, were administered once (p.o.) 60 min before the induction of the inflammatory response. The association of anethole + ibuprofen inhibited the development of the inflammatory response in both models used. This effect can be partially explained by the inhibitory action on the production of TNF and of COX isoforms. The isobologram analysis evidenced a synergistic effect between ibuprofen and anethole, because the combination of drugs showed a higher inhibitory potential than either drug alone.