the review analysis in different combination of western medicine adverse reaction conditions, to explore the combination of reasonable and effective solution. Methods: from the hospital is recorded in the computer system on a random sample of 2478 clinical data, analysis and review; According to the national ministry of health and food and drug administration issued the \"prescription management method\", \"the application principles of western medicine\" of the file such as the standard, the data for statistical analysis. Results: in al 2478 document, there are 178 prescriptions formula unreasonable phenomenon, cause after al kinds of adverse reaction, the incidence was 7.1%, such as fever, dizziness, nausea, chils, rashes, edema, etc. Clinical manifestations. Conclusion: many factors lead to improper drug use of adverse reaction, folow the guidance of pharmacology, scientific and rational combination can effectively reduce adverse reactions, enhance the clinical curative effect.