Results. Our data suggest that the therapeutic mechanism by which Pinellia ternata, Citrus reticulata, and their combinational prescription effectively treats asthma is based on reductions of eosinophil infiltration, eotaxin receptor (CCR3), histamine, OVA-specific IgE productions in serum, and Th2 cytokines (IL-5, IL-13) by marked reductions of IL-5 and IL-13 mRNA expression in lung tissue. The gene discussed is CCR3; the disease is asthma.