OBJECTIVE: To probe into the status of irrational drug use of COVID-19 in a hospital

discuss the main factors of irrational drug use

so as to formulate improvement measures and promote rational drug use in clinical practice. METHODS: Medical records of confirmed and suspected COVID-19 patients in the hospital from Jan. to Feb. 2020 were screened for prescription review

and the Pareto chart was used for statistical analysis of the review results

so as to find out the main factors of irrstional drug use. RESULTS: A total of 542 medical records were randomly reviewed

of which 107 were found with irrational drug use（ 19. 74%）. Totally 127 793 medical orders were included

of which 127 591 were rational medical orders

the rational rate of medical orders was 99. 84%.Among the 202 irrational medical orders

the main factors of irrational drug use were respectively compatibility contraindications or adverse interactions（ 60 items

29. 70%）

inappropriate usage and dosage（ 57 items

28. 22%） and inappropriate course of treatment（ 33 items

16. 34%） according to irrational drug use types. In terms of pharmacological effects of drugs

antiviral drugs（ 79 items

39. 11%）

respiratory medication（ 26 items

12. 87%）

immunostimulants（ 23 items

11. 39%） and antibiotics（ 20 items

9. 90%） were the main factors of irrational drug use. Adverse drug reactions were reported in 14 out of 107 medical records of irrational drug use（ 13. 08%）

and 28 out of 435 medical records of rational drug use reported adverse drug reactions（ 6. 43%）

the difference was statistically significant（ P = 0. 021）. CONCLUSIONS: Application of Pareto chart analysis can quickly and simply find out the main factors in irrational medical orders

and provide theoretical basis for clinical rational medication management decisions.