Has a red blister emerged in your mouth? Don’t panic. It’s a benign condition that will soon go away. But that doesn’t mean you have to live with the pain.

Suppose you feel pain in your mouth. When you look in the mirror, you see a red bubble on the side of your cheek. Although seeing a red-colored sore can be shocking, it’s likely nothing to worry about. In fact, a blood blister in the mouth is a common and benign condition.

The red bubble will go away on its own in a few days. But you can take measures to reduce the discomfort if the blister becomes bothersome. 

What causes a blood blister in the mouth?

When the upper layer of skin tissue is injured, a fluid-filled sac or blister forms to protect the skin from further damage. Sometimes, blood vessels are also broken, and blood fills the blister, giving it its red color. 

A blood blister differs from another benign wound — a canker sore. Canker sores appear as reddish ulcers covered by a white or yellowish film. Blood blisters are much darker red or purple.

Blood blisters are different from fever blisters. Before a fever blister develops, you may feel a tingling sensation. But blood blisters form spontaneously without warning. As their name suggests, fever blisters may occur with a fever and tend to appear on the lips and under the nose. Blood blisters develop solely in the oral cavity.

A blood blister develops for several reasons, including:

An injury. A blister may form when you bite hard on your cheek or if the mouth’s soft tissues burn from hot food. A bruise from a sharp-edged food, such as a chip, may cause a blister. A blister may develop following a dental procedure, such as a local anesthetic injection that nips the skin or while you’re fitted with a crown or denture.

Allergic reaction. Blisters can arise due to an allergic reaction to medications or foods. Highly acidic foods, in particular, can prompt the formation of a blood blister.

Thrombocytopenia. This condition refers to a low platelet count in the blood. Platelets help your blood clot, and red blisters in the mouth may develop if there isn’t enough in the blood.

Angina bullosa hemorrhagica. Angina bullosa hemorrhagica (ABH) is a rare disorder characterized by the sudden appearance of blood blisters in the mouth. One study estimated only 0.5 percent of people suffer from ABH. The blisters can last a few days before disappearing but can be painful. There is no known cause.

How to treat a blood blister

Since blood blisters are not harmful and typically resolve quickly, you don’t need to contact your doctor or dentist for treatment. But you should never try to pop the blister yourself as that could cause an infection.

If the blister becomes painful, you can contact your dentist or try some at-home remedies: 

Over-the-counter pain relievers. Over-the-counter anti-inflammatories can relieve the pain. Your dentist can also prescribe an antibacterial mouthwash.

Avoid food triggers. Hot, spicy, or salty foods can irritate the blister and hurt it more. Avoid those foods while the blister is present. You may want to eat a soft, bland diet for a few days until the blister is gone.

Although benign, a blood blister in the mouth should be brought to your dentist’s attention if it lasts longer than two weeks or makes chewing and swallowing difficult. If you notice pus draining from the blister, you could have an infection that needs treatment. Blisters that occur often should also be checked out. But chances are the red bubble in your mouth is a temporary annoyance soon to disappear.

We’ve served Oklahoma County for more than 30 years

Schedule an appointment at Espire’s Oklahoma City, OK, location today!  Dr. Kevin Rykard and Dr. Greg Stewart have served the Oklahoma County community for over 30 years. They provide both preventative and restorative care. If you have a blister in your mouth or another dental problem, they can diagnose and treat your condition with expertise and compassion. Don’t live near our Oklahoma City, OK, office? Find one of our other locations near you.

Oklahoma City, OK
12448 St Andrews Drive
Oklahoma City, OK 73120