Objective: To analyze the unreasonable use of outpatient prescription to guide clinical rational drug use. Method : Randomly check of 10

000 outpatient prescription in our hospital during July 2009 to December 2009

then analyze and classified statistics according to the instructions medicines

clinical pharmacology knowledge

and the published literature on the unreasonable prescription. Result : The total of 381 prescriptions was unreasonable. Some of reason was inappropriate choice of solvent

some was that the law did not meet the pharmacokinetics

some was pharmacological antagonism

some was duplicate medication

some was unreasonable to select drug

the others was adding of toxicity and changes in physical and chemical properties. Conclusion : The use of drugs is basically reasonable in our hospital

but we found a few problems.So we hope that physicians and pharmacists to strengthen the pharmaceutical knowledge in common.