Comparative study of local anaesthetic activity of H1-receptor antagonists

ABSTRACT

Local anaesthetic activity of various H[1] -receptor antagonists [Promethazine, diphenhydramine, antazoline, pheniramine, chlorpheniramine, cyclizine, clemastine, astemizole and terfenadine] was studied by Intradermal wheal method in rabbits. Comparison of each drug was made with the standard local anaesthetic, lignocaine. Only promethazine, diphenhydramine, antazoline and cyclizine had local anaesthetic activity. Promethazine was the most potent drug in this regard. Pheniramine, chlorpheniramine, astemizole and terfenadine did not show any local anaesthetic activity in this study