Subjective/objective symptoms (itching, papula, erythema, lichenification, desquamation, scratching, erosion) and the levels of IgE, LDH, interleukin (IL) -6, thymus and activation-regulated chemokine (TARC) were compared before and after administering olopatadine hydrochloride (ALLELOCK tablets) to 17 atopic dermatitis (AD) patients. Subject/objective symptoms improved significantly after administering the agent, and the total dosage of the combined topical steroids was also significantly decreased after administration (p<0.05), although IgE, IL-6 and LDH levels did not change, TARC was significantly decreased (p<0.05). The correlation between the levels of IgE, IL-6, LDH and TARC before and after the administration was examined. There was a positive correlation between IgE and TARC (r=0.62, p<0.01) and between IL-6 and TARC (r=0.78, p<0.01). Olopatadine hydrochloride is therefore useful in improving the symptoms in AD, and TARC may be used as an indicator of the symptom improvement.