1. people who are allergic to pifenidone capsules, 2. the researchers judged that the compliance of the subjects was not good, 3. those who cannot take drugs through gastrointestinal tract, 4. any significant clinical or laboratory abnormalities that may affect the safety assessment, such as: serum creatinine > 2mg/dL or 176.8mmol sputum alt, AST >=2.5 ULN or TBIL >=1.5 ULN, 5. patients with severe liver disease, 6. pregnant and lactating patients, 7. patients with severe nephropathy or requiring dialysis treatment, 8. those who need to take fluvoxamine at the same time (a drug for the treatment of depression or obsessive-compulsive disorder).

1. people who are allergic to pifenidone capsules, 2. the researchers judged that the compliance of the subjects was not good, 3. those who cannot take drugs through gastrointestinal tract, 4. any significant clinical or laboratory abnormalities that may affect the safety assessment, such as: serum creatinine > 2mg/dL or 176.8mmol sputum alt, AST >=2.5 ULN or TBIL >=1.5 ULN, 5. patients with severe liver disease, 6. pregnant and lactating patients, 7. patients with severe nephropathy or requiring dialysis treatment, 8. those who need to take fluvoxamine at the same time (a drug for the treatment of depression or obsessive-compulsive disorder).