Active cutaneous anaphylaxis (ACA) was studied in the ear of female BALB/c mice. Mice were immunized with ovalbumin in the presence of aluminium hydroxide gel or complete Freund's adjuvant (CFA). Two weeks after the immunization, ACA was elicited in the mouse ear by injecting 10 microliters of antigen solution intradermally into the ear lobe. ACA was assessed by the amount of extravasated dye, which was given intravenously just after the antigen injection. Antiallergic drugs (tranilast, ketotifen and azelastine), antihistamines (chlorpheniramine, diphenhydramine and mequitazine), beta-stimulants (isoproterenol and salbutamol), theophylline and glucocorticoids (hydrocortisone, prednisolone and dexamethasone) inhibited the reaction significantly. These drugs inhibited both ACA in mice immunized with alum-precipitated antigen and ACA in mice injected with CFA-emulsified antigen similarly. ACA in the mouse ear might be a useful tool for studying drugs for allergy.