Influence of tolfenamic acid on airway contractility in guinea pigs.

The effect of the NSAIDs tolfenamic acid and indomethacin was tested on acetylcholine-induced and antigen-induced contractions in guinea pig airways. Indomethacin potentiated antigen-induced contractions while tolfenamic acid showed dilatory properties. The effects of the drugs on acetylcholine-induced contractions showed no significant differences; indomethacin had a slightly increasing tendency while tolfenamic acid reduced the contractile response. These results indicate that tolfenamic acid does not have bronchoconstrictive properties, which is a common side effect of other NSAIDs in asthmatics.