Mouth blisters are irritating and occasionally embarrassing. They may be inside or outside of the mouth. There are various types of mouth lesions, including the common cold sore and canker sore. Brought on by a variety of causes, mouth blisters may last several days. Some types are treatable and others go away on their own.
Canker sores are ulcers found inside the mouth. Theses mouth blisters are also called aphthous ulcers. They are visible to the naked eye. Whitish yellow in color, these shallow sores appear with a red border. Though basically round, they are irregular in shape with jagged edges.
A canker sore may develop on the cheeks, gums, tongue, or lips — just about anywhere inside the mouth. These mouth blisters range in size, though they are typically smaller than the diameter of a pea. They may cluster or appear singularly. Mouth blisters like this cause additional irritation when eating or even talking. They are extremely painful to the touch.
A canker sore generally goes away on its own within five to 10 days. Though tremendously painful at any size, any canker sore larger than 0.5 inch (1.27 cm) in diameter should be seen by a physician. A physician might be able to shed light on whether it’s actually a different type of ulcer or mouth blister.
Canker sores may be hereditary. They are not contagious, though. Though there is not a cure for these mouth blisters, there are numbing pastes that help ease the pain of a breakout. Staying away from acidic products such as tomatoes and orange juice will also help ease the pain of a canker sore.
Unlike canker sores, cold sores are contagious. Also called oral herpes, cold sores are lesions found surrounding the outside of the mouth. They are caused by the herpes simplex virus type 1 (HSV-1).
Cold sores can also be caused by herpes simplex virus type 2 (HSV-2), which is commonly known as genital herpes. The oral herpes virus may be transmitted through sexual acts, particularly when the infected person is shedding the virus. It may also be spread through kissing and sharing beverages.
HSV is a latent virus, meaning that after the first breakout, it often lies dormant beneath the skin for some time. In the case of oral herpes, a cold sore may occasionally appear during a particularly stressful time. A canker sore, on the other hand, may be triggered after a minor cut on the lip or accidental bite of one’s cheek.
Oral herpes mouth blisters are red and filled with fluid. These cold sores usually last a week or two, and crust over before disappearing without leaving a scar. Those who have experienced many breakouts might be familiar with a tingling or slightly itchy sensation that occurs right before a breakout.
