Chronic obstructive pulmonary disease （COPD） is a heterogeneous lung condition characterized by persistent and often progressive airflow obstruction， including airway abnormalities （e.g.， bronchitis and bronchiolitis） and chronic respiratory symptoms （e.g.， dyspnea， cough， and expectoration）. It is one of the leading causes of death worldwide. According to the theory of traditional Chinese medicine （TCM）， the lung and large intestine are interior-exterior related. Therefore， COPD can be treated from both the lung and intestine by the methods of tonifying and invigorating lung， spleen， and kidney， dispelling phlegm， and expelling stasis. Gut microbiota plays a key role in human immunity， nerve， and metabolism and may act on COPD by affecting the structures and functions of lung and intestine tissue and regulating lung inflammation and immunity. TCM can restore the balance of gut microbiota， which is conducive to the recovery from COPD. For example， the treatment method of tonifying lung and invigorating kidney can regulate gut microbiota， alleviate pulmonary and intestinal injuries， and improve lung immunity. The treatment methods of dispelling phlegm and expelling stasis can regulate gut microbiota and reduce pulmonary inflammation. According to the TCM theory of lung and large intestine being interior-exterior related， this review elaborates on the connotation of TCM in the treatment of COPD by regulating gut microbiota， aiming to provide new ideas for the clinical treatment of COPD via gut microbiota.

Community-acquired pneumonia （CAP） is a respiratory infection which takes a long time to fully recover after clinical symptoms are alleviated in the short term. It affects the physical health and quality of life of the patients in the long term and can occur repeatedly， which is related to inflammation， immunity， and the coagulation function. Lung Qi deficiency and collateral stasis are the key pathogenesis of CAP at the recovery stage. The development of CAP is accompanied by the decreased production and the increased consumption of Qi， which results in lung Qi deficiency. At the same time， heat pathogen forces the blood to move improperly， which depletes Qi and damages fluid， resulting in lung collateral stasis. Lung Qi deficiency and collateral stasis are causal and influence each other. The patients at the recovery stage of CAP generally present deficient lung Qi and healthy Qi， impaired immune function， and weakened defense function. However， pathogenic Qi， coagulation function changes， and thrombosis exist， and some coagulation factors are associated with the prognosis of CAP. The Chinese medicines for tonifying lung and supplementing Qi can help replenish healthy Qi， consolidate the body foundation， and regulate the inflammation. The Chinese medicines for activating blood and resolving stasis can dredge the lung collaterals， clear the pathogenic Qi， improve the microvascular circulation， and inhibit the inflammatory response. The Chinese medicines for supplementing Qi and activating blood can replenish healthy Qi and dispel pathogen to regulate immunity， inhibit inflammation， and alleviate the clinical symptoms， thus promoting the recovery from pneumonia. From lung Qi deficiency and collateral stasis， this paper summarizes the application and explains the scientific connotation of supplementing Qi and activating blood in preventing relapse after recovery of CAP， providing ideas for using this method to assist in preventing relapse after recovery of CAP.

Chronic obstructive pulmonary disease （COPD） is one of the most common chronic diseases of the respiratory system in the clinic. The disease has a long course and is difficult to cure， which seriously threatens human health. Airway mucus hypersecretion （AMH） is an independent risk factor for COPD and has a significant impact on the development and prognosis of the disease. The review finds that the abnormal proliferation of goblet cells and the excessive secretion of mucin are the direct causes of AMH. The pathogenesis of AMH may be closely related to the inhalation of heterogeneous particles， airway inflammation， the imbalance of mucin/water salt ratio， and the regulation of related signaling pathways. Traditional Chinese medicine （TCM） believes that AMH of COPD belongs to the category of lung distension with phlegm-fluid retention syndrome， and the disease is mainly treated from phlegm on the basis of lung distension. This article summarizes the relevant research in the field of TCM in recent years and finds that the single TCM that effectively intervened AMH of COPD is mainly phlegm-resolving TCM， and the main active ingredients of TCM are flavonoids， terpenoids， phenols， and alkaloids. The main TCM compounds are mainly designed to remove heat-phlegm， warmly resolve cold-phlegm， dry dampness to eliminate phlegm， invigorate Qi， promote blood circulation and dispel phlegm， and invigorate lung， spleen， and kidney. Its mechanism of action may be direct inhibition or indirect inhibition of airway epithelial goblet cell metaplasia and mucin expression by inhibiting airway inflammation， regulating aquaporins to correct the imbalance of mucin/water salt ratio， and regulating signaling pathways， so as to reduce mucus oversecretion in COPD. However， there are still some problems. For example， the research mainly focuses on TCM compounds instead of the single TCM or its effective components. The research on the mechanism of action is not thorough enough， and the research results are not interoperable. The clinical transformation rate of basic research is insufficient. This article systematically reviews the research status of AMH in the treatment of COPD with TCM and puts forward some thoughts on the existing problems， so as to provide a reference for clinical rational medication and in-depth research.

Viral pneumonia （VP） is an inflammatory disease caused by one or more viruses that infect the upper respiratory tract and spread downward. Causing varying degrees of pulmonary parenchymal damage， VP poses a serious threat to the society and public health. The treatment of VP now faces the dilemma of drug shortage， since Western medicine can only alleviate symptoms and lacks specific treatment methods. In traditional Chinese medicine （TCM）， VP is assigned as an epidemic disease， with the etiology attributed to epidemic toxin and six excesses and the pathological factors of dampness， heat， toxin， deficiency， and stasis. The basic pathogenesis of VP is Yin-Yang imbalance， dysfunction of Zang-Fu organs， and healthy Qi deficiency. Accordingly， the treatment should follow the principle of replenishing healthy Qi and expelling pathogen. The treatment method of VP is mainly developed based on syndrome differentiation of six meridians， defense-Qi-nutrient-blood， and triple energizer. Xuanfei Baidu prescription （XFBD） is an effective prescription developed by Academician ZHANG Boli and Professor LIU Qingquan by literature research and selection of multi-component Chinese medicine. It is the product of modern research combined with TCM. XFBD is modified from Maxing Shigantang， Maxing Yigantang， Tingli Dazao Xiefeitang， Qianjin Weijingtang， and Buhuanjin Zhengqisan. It is mainly used to treat epidemic diseases with the syndrome of dampness toxin stagnating in the lung， with the effects of ventilating lung and resolving dampness， clearing heat and expelling pathogen， purging lung， and removing toxin， demonstrating the potential for the prevention and treatment of VP. This paper reviews the research progress of XFBD in combating VP in terms of the prescription composition， compatibility ideas， indications， and clinical new applications， as well as the pharmacological mechanisms of inhibiting virus， reducing inflammation， regulating immune system， ameliorating pulmonary fibrosis， and modulating intestinal flora. In addition， we put forward our thoughts and suggestions on the problems in the research， with a view to informing the clinical use of drugs and the basic research on the treatment of VP including COVID-19.