Alterations of the entire immunity profile of bronchial asthma patients have been studied following a half-year long Ketotifen treatment. It was observed that this drug leads to the normalization of the immunity state in a whole series of parameters and that it thus contributes on a large scale to the reestablishment of normal regulation. These findings may be utilized for expanding the possibilities of application of this preparation upon other immunopathological states that bronchial asthma and the atopic diseases.