The interaction of histamine with other bronchoconstrictor mediators.

The lack of therapeutic efficacy of antihistaminic drugs in the treatment of asthma has led to the search and discovery of other bronchoconstrictor agents, particularly leukotrienes, thromboxanes, and platelet-activating factor. However, specific receptor antagonist for any of these substances have also not been particularly effective in inhibiting allergic bronchoconstriction. It is now generally accepted that histamine, arachidonic acid metabolites, platelet-activating factor, and possibly other substances are all involved to varying degrees in asthma and may indeed interact. This paper reviews the interaction of these mediators and how they contribute to airway hyperreactivity.