This study is to evaluate the clinical efficacy and safety of Jin-shui Huan-xian Formula in retarding the decline of pulmonary function in IPF, generate high - quality clinical evidence, and establish a treatment plan of Jin-shui Huan-xian Formula for retarding the decline of pulmonary function in Idiopathic Pulmonary Fibrosis（IPF）
Patients who meet the diagnostic criteria for IPF.
Pulmonary function: The percentage of forced vital capacity (FVC) to the predicted value is ≥ 50%; and the percentage of the diffusing capacity of the lung for carbon monoxide (DLCO) to the predicted value is ≥ 30%.
Patients who meet the syndrome - differentiation criteria for lung - qi deficiency syndrome, lung - and - kidney qi deficiency syndrome, etc.
Aged between 40 and 85 years old.
Patients in the acute exacerbation phase of IPF.
Patients complicated with other pulmonary diseases such as chronic obstructive pulmonary disease (COPD), lung cancer, active pulmonary tuberculosis, bronchiectasis, and pulmonary embolism.
Patients with severe joint, peripheral nerve, and peripheral vascular diseases that affect limb movement and who are bed - ridden for a long time and cannot complete the six - minute walk test.
Patients complicated with severe cardiovascular and cerebrovascular diseases (malignant arrhythmia, unstable angina pectoris, acute myocardial infarction, heart function grade 3 or above, stroke, cerebral hemorrhage, etc.).