Chlorhexidine is a cationic surface-active antiseptic with broad-spectrum antimicrobial effect. Different dosage forms of chlorhexidine treat different diseases, and it can be used for oral diseases as well as burns, scalds and other diseases, and it can be used to disinfect the skin. As a cationic surface-active preservative, chlorhexidine can be adsorbed on the permeability barrier of bacterial plasma membrane, change the permeability of bacterial cell membrane, so that the cell contents leak out, and then play an antibacterial effect. Chlorhexidine treats different diseases according to different dosage forms. In general, solution preparations like chlorhexidine gluconate solution and gargle can be used for oral diseases such as mouth ulcers, and chlorhexidine acetate solution can be used for disinfection of skin and mucous membranes. Chlorhexidine ointment and other ointment preparations can be used for the treatment of mild and small scalds and burns. Take the commonly used compound chlorhexidine gargle in stomatology as an example, its adverse reactions include occasional allergic reactions or superficial desquamation of the oral mucosa, long-term use can make the surface of the oral mucosa and teeth coloring, yellowing of the tongue, and altered sense of taste. Chlorhexidine should not be used without authorization, and should be used under the guidance of a medical professional. Allergic to chlorhexidine is prohibited, lactating women should be cautious.