The fever may come back after the fever of interferon with polyethylene glycol has subsided, which may be caused by an adverse reaction to the drug, and it is recommended that the drug be temporarily discontinued. Polyethylene glycol interferon is mainly used to treat chronic hepatitis B and C with compensated liver disease. Common adverse reactions include fever, headache, upper respiratory tract infection, flu-like illness, gastrointestinal discomfort, etc. Therefore, it is possible to get a fever again. If this happens, the drug should be temporarily suspended, and the symptoms will gradually disappear after stopping the use of the drug. Interferon with polyethylene glycol should be used at an age greater than or equal to 18 years, renal insufficiency, allergy to interferon with polyethylene glycol is prohibited to use the drug, pregnant women and lactating women should be cautious. The use of interferon should be used under the guidance of a physician, avoid self-medication, in order to avoid adverse consequences.