Statistical analyses will be performed by hospital statisticians using SPSS version 18.0.0 (2009). The primary outcomes will be the change in Mean Total Symptoms Score (MTSS) from baseline between groups. Secondary outcome measures will include assessment of (1) the change in MPS between groups; (2) the change in MNW between groups. (3) the change in GSS by medical investigator between groups; (4) the comparison of area under the curve (AUC for the trend) for MTSS, MPS, MNW, GSS and DCS between the groups during the 4-week period; and (5) the comparison of total dose of anti-histamine used by each group compared to baseline within the study period. All data will be analyzed using paired student's t-test.