Objective To observe the therapeutic effect of intravenous drip of Ligustrazine Injection(LI) for cold-type asthma in children and to explore its possible mechanism.Methods Seventy asthma children at the stage of acute attack were randomized into the treatment group and the control group.The two groups received routine western medicine and the treatment group received intravenous drip of LI additionally.The serum levels of interferon ?(IFN-?) and interleukin-4(IL-4) were observed,and the total therapeutic effect as well as the effect on main symptoms was evaluated.Results The total effective rate and the effect on the main symptoms in the treatment group were superior to those in the control group(P