There are many reasons for anal swelling, and anal swelling should be analyzed for its causes, the common causes are the following: first, there may be a long-term diet of some spicy, irritating foods, such as mustard or chili, after drinking a lot of alcohol can lead to hemorrhoid nucleus stagnation, swelling, hemorrhoid vein bleeding, which can be manifested in the perianal area as annular hemorrhoid nucleus stagnation, possibly caused by mixed hemorrhoids anal swelling. This situation should be actively given medication, you can use warm salt water or Chinese medicine for fumigation, such as bitter ginseng soup or five times the seed soup, it can play a role in clearing heat, dampness, and reduce swelling. Secondly, if the patient has diarrhea, which causes anal sinus infection or anal gland infection, it spreads along the anal canal to the perianal area and forms a perianal abscess, which manifests as a hard mass at the anal opening, and can be clearly diagnosed by performing perianal ultrasound.