A blood blister is a type of wound that can happen anywhere on the body, usually as a result of brusing, pinching, or rubbing the skin so that the tissues and blood vessels are damaged in some way. The redness occurs because the blood and pus pools underneath the surface, forming a round lump, thus creating a type of internal wound, rather than an open one that bleeds.
A blood blister in the mouth is somewhat different; it can occur when accidentally biting down onto the inside of the lip or cheek, having braces or a retainer pinch or scrape the skin inside the mouth, a mishap with a fork or toothbrush, or as a result of medications, diet, or an illness. It is not to be confused with a mouth ulcer, which also can result from any of the above, but is an open wound that is white in color and may or may not swell into a lump form. Unless a blood blister in the mouth becomes a chronic problem, enlargens or creates further discomfort or problems, or doesn’t heal on its own, visiting the doctor or dentist is not necessary.
Treating a Blood Blister
As with any wound that bruises or swells, a blood blister should not be popped. Doing so will scar the area, or make the blister take longer to heal, putting you at risk for further infection. Instead, reduce swelling, minimize discomfort, and allow it to heal. This can be done from home by doing the following:
1. Apply a cold compress to the blood blister at the onset of the wound and before/after eating or brushing the teeth to relieve pain and swelling.
2. Take an aspirin or ibuprofen as needed, and either swish the mouth with an antibacterial mouth wash or water mixed with a teaspoon or two of salt or baking soda (if it can be tolerated) 1 to 2 times a day.
3. Refrain from eating or drinking foods that will irritate the area, such as anything sharp or acidic.
4. Instead of brushing your teeth with a toothbrush, brush with your finger, or use mouthwash exclusively until you can brush safely without irritating the blister.
Unless you have other factors contributing to the blood blister, it should heal within a week. Larger ones may take longer, especially if it is around the salivary gland on the inside of the lip. Ultimately, however, if you do not see improvement, or if it recurs, it may be necessary to visit the doctor for further examination and medication.