Macrolide antibiotics including erythromycin, roxithromycin, clarithromycin, and azithromycin have antibacterial effects. In the last decade, it has been found that macrolide antibiotics also all have anti-inflammatory effects, and this effect is not their antibacterial effect because their application is well below the minimum inhibitory concentration. The anti-inflammatory effects of macrolide antibiotics are not well understood and may act through two pathways. 1, modulating the body’s immune function and inhibiting tissue damage caused by immune response. 2, inhibit or interfere with the formation of bacterial biofilm. Long-term low-dose macrolide antibiotics have been widely used in chronic rhinosinusitis, chronic obstructive pneumonia, tracheobronchitis and other chronic inflammatory conditions. The application course can be as long as 1-2 years with good safety.