Chlorhexidine, or cotrimoxazole, does not necessarily need to be rinsed out, but can be used in accordance with personal preference. Compound chlorhexidine gargle belongs to antibacterial drugs, more commonly used in the treatment of a variety of factors caused by bleeding gums, periodontal abscesses, and oral mucous membrane and other diseases of adjuvant therapy, such as gingivitis, pericoronitis and oral mucositis. Occasionally, superficial desquamation of the oral mucosa or allergic reactions have been observed in some populations following the use of this drug. Long-term use of this drug can make the teeth and oral mucosa surface teeth coloring, so that the sense of taste changes, yellow tongue coating and so on. Therefore, this drug should be spit out after gargling, not swallowed, and should not be used for a long time. The main components of this drug are chlorhexidine gluconate and metronidazole, after spitting out the gargle, a small amount of liquid will remain on the oral mucosa, and the amount will gradually decrease with the swallowing of saliva. If there is a strong medicinal odor in the mouth or significant discomfort in the mouth after oral intake, then you can rinse your mouth. If there is no rejection of the taste of the medicine, or the mouth does not appear other odor, then there is no need to rinse the mouth, usually does not cause discomfort in the mouth. If there is any discomfort, medical treatment should be sought promptly.