Treatment of Pulmonary Fibrosis Due to COVID-19 With Fuzheng Huayu

Inclusion criteria (I) Discharged patients fulfilling the diagnostic criteria of COVID-19 (China Diagnosis and Treatment Protocol for COVID-19 (Trial Version 7); (II) COVID-19 RNA in respiratory specimens or blood specimens of patients is negative (\>2 times), assayed by real-time fluorescent polymerase chain reaction test (RT-PCR); (III) Pulmonary CT scans within 7 days showed that there were still unabsorbed inflammation or pulmonary fibrosis in the lungs; (IV) Age 18-70. Exclusion criteria * Patients who have undergone lung surgery that affects pulmonary function, such as pulmonary transplantation, pulmonary resection, pulmonary volume reduction, etc; * Relying on mechanical ventilation to maintain pulmonary function, such as ventilators; * Combined with chronic pulmonary diseases affecting pulmonary function, such as chronic obstructive pulmonary disease, other known causes of interstitial pulmonary disease; * Patients with diseases affecting cardiac function, such as pulmonary circulation hypertension, heart failure, peripheral vascular disease, fibromyalgia, and pacemaker installation; * Patients with severe underlying diseases affecting survival, including uncontroled cardiac, renal, digestive, hematological, neuropsychiatric, immune, metabolic diseases, malignant diseases and severe malnutrition; * Resting heart rate \>120 times/min; * Systolic blood pressure \> 180 mmHg, diastolic blood pressure \> 100 mmHg; * Unstable angina pectoris or myocardial infarction occurring within the last month; * Severe obesity (BMI \> 30 kg/m2); * Allergic constitution, allergic to the drug components involved in the treatment program; * Pregnant or breastfeeding women; * Patients with disabilities who are unable to complete the efficacy evaluation questionnaires; * Difficult collaborators with poor mental health status, suffering from mental illness, patients without self-control, unable to express clearly; * Those who are participating in other clinical trials; * According to the investigator's judgment, patients whose enrollment complications or poor compliance will affect the efficacy and safety evaluation.