Ketotifen is an established antihistamine drug, widely used in pediatric clinical practice in Japan. The objective of the study was to compare the efficacy and safety of cetirizine hydrochloride versus ketotifen dry syrup on children 7 years and older with perennial allergic rhinitis.

Inclusion Criteria:

• had at least one of the 3 symptoms: sneezing, nasal discharge or nasal congestion;
• severity of nasal symptoms was moderate to severe during the observation period;
• criteria for allergic etiology of the disease fulfilled, i.e., positive IgE antibody test and positive eosinophil count in nasal discharge.

Exclusion Criteria:

• history of hypersensitivity to the ingredients of cetirizine or ketotifen formulation or to hydroxyzine;
• history of drug hypersensitivity;
• history of convulsive disorder;
• vasomotor rhinitis or eosinophilic rhinitis;
• asthma requiring treatment with adrenocortical hormones;
• concomitant diseases which could impede the efficacy evaluation of the study drug;
• subjects in the ascending-dose phase of hyposensitization therapy or non-modular therapy and who had not received the maintenance dosage;
• pollen allergy;
• malignant neoplasm.