Erythromycin is a class of antibacterial drugs with antimicrobial effect, it belongs to the macrolide class of antibiotics, mainly used for a variety of infections, including respiratory tract infections, skin infections, as well as initial syphilis, genitourinary system infections, oral infections, etc.. Its antibacterial spectrum is actually similar to that of penicillin, with strong inhibitory effects on Gram-positive bacteria such as Staphylococcus, Streptococcus pyogenes and Streptococcus pneumoniae, and considerable inhibitory effects on Gram-negative bacteria such as gonococcus, Helicobacter and Haemophilus influenzae. In addition, it has inhibitory effect on mycoplasma, chlamydia, nocardia, a few mycobacteria and amoeba. However, it should be noted that Staphylococcus aureus is easily resistant to the drug, and some gastrointestinal reactions may occur after the drug, such as nausea, vomiting, abdominal pain, diarrhea, and possibly pain in the mouth and tongue, loss of appetite, etc.