OBJECTIVE: To probe into the off-label use of anti-tumor drugs in the hospital. METHODS: Totally 2 000 prescriptions with anti-tumor drugs were randomly selected from the outpatient pharmacy of the hospital in 2021. According to the drug instructions

the off-label use of anti-tumor drugs in the outpatient department in terms of dosage

suitable population

indication and route of administration was analyzed and evaluated. RESULTS: The incidence of off-label use of anti-tumor drugs in the hospital was 31.50%（630/2 000）. The proportion of off-label drug use prescriptions in male patients was significantly higher than that in female patients（χ~2=21.33

P=0.00）

and the proportion of off-label drug use prescriptions in chief physicians was significantly lower than that in attending physicians（χ~2=38.72

P=0.00） and associate chief physicians（χ~2=31.09

P=0.00）

with statistical significant differences. Among the 630 off-label drug use prescriptions

the main types of off-label drug use were off-label route of administration（266 prescriptions

42.22%） and off-label indications（235 prescriptions

37.30%）. Anti-tumor chemotherapeutic drugs（397 prescriptions

63.02%） and targeted drugs（129 prescriptions

20.48%） took the lead of off-label drug use. There were more off-label indications for the digestive system tumors（182 prescriptions

28.89%）

chest tumors（165 prescriptions

26.19%） and urological tumors（107 prescriptions

16.98%）. CONCLUSIONS: Off-label drug use of anti-tumor drugs is widespread in the hospital

mainly off-label indications and off-label route of administration

which need to be taken seriously to ensure the effective and safe use of drugs by patients in a scientific and rational management manner.