PURPOSE: To obtain an antiallergic agent having low toxicity and no side effects, not showing immunosuppressive action, selectively controlling production of IgE, comprising a specific compound as an active ingredient.

CONSTITUTION: This antiallergic agent comprises a compound of th formula (R1 to R3 are H, halogen, OH, amino, cyano, carbamoyl, carboxyl, carboxyalkenyl, carboxyalkyl or alkyl) such as 5-(carboxymethyl)imidazole as an active ingredient. A dose of the compound as the active ingredient is usually 50mg-5g per adult daily and preferably administered once or dividedly.