A large number of studies have shown that multiple traditional Chinese medicine (TCM) compounds, single herbs, and monomers have effects on inhibiting drug-resistant bacteria in both in vitro and in vivo studies such as MRSA, Acinetobacter baumannii, and Pseudomonas aeruginosa.

The mechanism of treating drug-resistant bacteria in TCM mainly includes the following two aspects: eliminating plasmid and inhibition of the active efflux pump system. Forsythia decoction can inhibit the active efflux pump of A. baumannii, resulting in the variation of an adeB sequence of efflux pump coding gene.

In addition, TCM has a large impact on the production of the inactivating enzyme of antimicrobials to reverse the drug resistance. To inhibit the growth and reproduction of bacteria, Chinese medicinal herbs can alter the structure of bacterial cell wall to affect permeability. Some herbs such as rhubarb and berberine can restrain the formation of biofilms to inhibit the MRSA.

Notably, the antibacterial activity of TCM with little side effects is equivalent to that of antibiotics. A study showed that Chinese medicine, Mayushihuang decoction, has the same efficiency with teicoplanin for clearing MRSA; however, distinct adverse effects were not detected in the TCM group as compared to abnormal hepatorenal function in the teicoplanin group.

The combination of traditional Chinese medicine (TCM) intravenous preparations with conventional antibiotics can effectively improve the clinical efficacy of community-acquired pneumonia (CAP) and promote the early rehabilitation of patients, thereby reducing the rate of mortality of the patients. Previous studies showed that Xiyanping injection (TCM injections are approved by the China Food and Drug Administration for the treatment of respiratory infection; the main ingredient is andrographolide sulfonate) combined with piperacillin and sulbactam significantly improved the clinical efficacy of pulmonary infection in the elderly.

Pulmonary infection is the most common complication and cause of death in stroke patients. Compared to simple symptomatic support treatment, the recovery rate and efficiency of Qingjin huatan decoction (famous TCM recipe composed of Scutellaria baicalensis, Fructus gardeniae, Fritillaria thun-bergli, for clearing heat and reducing phlegm) combined with Xiaochengqi decoction (purgative prescription) in the treatment of apoplexy-related lung infection is greatly improved. The symptoms of patients with pulmonary infection complicated with sepsis were significantly improved after treatment with the addition of Shengjiang powder combined with basic Western medical treatment including antibiotics and expectorant application. Consequently, the APACHE2 score was significantly reduced, and the levels of inflammatory cytokines, such as CRP, TNF-α, and IL-6 were also significantly reduced.

Present, several studies on the anti-virus activity of single Chinese medicinal herb, such as Fructus forsythiae, Radix isatidis, and Scutellaria baicalensis, using modern technology confirmed the effective constituent and materials, as well as the functional mechanism of the relevant parts. A systematic analysis found that TCM decoction and Ganmao capsule (a non-prescription Chinese patent medicine composed of some herbs for clearing heat and toxicity is commonly used in treating cold and flu) had better effects on the treatment of H3N2 and influenza B, respectively, than amantadine and ribavirin.

In terms of anti-inflammation, TCM can alleviate the damage caused by excess inflammatory reactions initiated by a virus. The single and compound Chinese medicinal herbs which can cause clearing heat and toxicity could decrease the cytokine storm resulting from the production of several species of pro-inflammatory cytokines and anti-inflammatory cytokines aim to improve the injury of tissue and organs. In turn, this phenomenon promotes blood circulation and removes stasis, thereby confining the inflammation and promoting its absorption. In the case of SARS, a rapidly spreading infectious disease, TCM combined with corticosteroids during the early stage of the outbreak could decrease the mortality by promoting innate immunity to relieve inflammation.

Subsequently, the TCM compounds of Chinese herbs analyzed based on the theory of strengthening healthy Qi and clearing pathogenic factors with the feature of multicomponent, multi-channel, and multiple targets exerted a synergistic effect on inhibiting the virus directly, relieving the immunopathological injury, and controlling the inflammatory reaction caused by virus infection.

The overall characteristics of TCM in treating viral infectious diseases are that it can significantly lighten the symptoms and bring down the fever quickly; however, the time of viral nucleic acid to be negative in TCM is slower as compared to the chemical antiviral drugs.

Some randomized controlled trials showed that Maxingshigan decoction (a classical TCM recipe that is commonly used for pneumonia composed of Chinese ephedra, apricot kernel, gypsum, licorice), Yinqiaosan decoction (a famous TCM recipe mainly composed by Lonicera japonica and Fructus forsythiae is commonly used for cough and sore throat caused by virus infection), and modern Chinese patent medicine Lianhua qingwen capsules (a TCM capsule, which is approved by the China Food and Drug Administration for the treatment of flu) relieve the clinical symptoms of influenza patients and shorten the time of disease progression.