When accidentally biting or eating hard food on the tongue, it can cause small blood vessels to rupture in the mucosa under the tongue, forming small localized blood blisters. If the blood vessels do not clot within a short period of time, the blisters will gradually become larger. For small vesicles, no treatment is usually needed. Within 1-2 days, the blood inside the vesicle will be slowly absorbed by the surrounding tissues, and the vesicle will deflate and return to normal. However, for rapidly progressing vesicles, or vesicles located close to the pharynx, which are likely to cause choking, treatment by blood extraction is required, and a sterile syringe needle should be used to locally extract blood from the vesicles. However, special care should be taken not to break the wall of the blood blisters in a large area, as this will easily expose the traumatic surface under the tongue in a large area, which will easily cause infection of the tongue.