Pirfenidone is taken at a dose of 200-600mg three times daily, and should be administered under the direction of a physician. Pirfenidone has antifibrotic and anti-inflammatory effects and is indicated for the treatment of mild to moderate idiopathic interstitial pulmonary fibrosis. It is administered orally and is recommended to be taken with meals. The dosage is to start with 200mg per time, three times a day, and gradually increase the dosage, the maintenance dosage is 600mg per time, three times a day. The exact dosage regimen should be determined by a medical professional based on the patient’s condition. Pirfenidone may cause adverse reactions such as loss of appetite, stomach upset, drowsiness, dizziness, hepatic impairment, allergy, rash, and photosensitivity reactions. It is contraindicated in people who are allergic to the product, patients with severe liver and kidney disease, pregnant and lactating women. The medication should be administered under the assessment and guidance of a physician, with regular evaluations, and if any serious side effects occur the medication should be discontinued in time to seek medical attention.