Pirfenidone is not a targeted drug and has collagen synthesis inhibiting, anti-inflammatory and antioxidant effects, patients need to use the drug in strict compliance with the doctor’s instructions. Pirfenidone is a pyridone analog that prevents and reverses fibrosis and scarring. Clinically, it is mainly used to inhibit collagen synthesis, anti-inflammatory and antioxidant effects. However, the drug is contraindicated in people who are allergic to any of its components, and it is also contraindicated in patients who are pregnant, breastfeeding, have moderate liver disease, severe renal dysfunction, taking of ofloxacin, or require dialysis. Meanwhile, patients who have missed a dose during the period of taking the drug are required to make up for it, but they need to ensure that the interval between doses is more than 3 hours, and they should not take more than one dose at a time. For patients who have stopped taking the drug for more than 14 days, it is necessary to start taking the drug from the initial dose, and patients should avoid upper respiratory tract infections during the period of taking the drug, so as to avoid acute exacerbation of symptoms or conditions. It is recommended that patients take pirfenidone in strict compliance with medical advice, and understand the relevant precautions before using the drug, and do their own care.