Mechanism of the action of amoxanox (AA-673), an orally active antiallergic agent.

Amoxanox inhibited immunologically stimulated and LTD4-induced bronchoconstriction in laboratory animals. Amoxanox, like DSCG, inhibited rat IgE-mediated PCA and histamine release from rat peritoneal mast cells, and suppressed immunologically stimulated or calcium ionophore A23187-induced SRS-A generation in rat peritoneal cavity and guinea pig lung fragments. This compound also reduced the contractile response of guinea pig lung parenchymal and ileal strips to LTD4, but did not significantly affect the response of the ileum to either histamine or acetylcholine. Therefore, the antiallergic action of amoxanox seems to be associated with inhibition of chemical mediator release and antagonistic activity on SRS-A.