What Is a Mucous Cyst?

Mucous Cyst (Mucocele) Overview

Mucous cysts can appear on the inner surface of your lip or other areas of the body.
Mucous cysts can appear on the inner surface of your lip or other areas of the body.

If you have a smooth, soft lump on the inner surface of your lower lip, on your tongue, or anywhere else inside your mouth, it might be a mucous cyst. Sometimes, mucous cysts can occur on other parts of the body. 

People also call these cysts “mucoceles.” Mucous cysts are just what they sound like. They are lumps or sacs filled with mucus

Mucous cysts might look bluish in color. If there’s bleeding into the cyst, it might appear red. Other times they are translucent or white. They are often shiny and firm. Mucous cysts may form near the surface of skin or they may be deeper.

Most mucous cysts are small—less than 2 centimeters across. But there are cases of mucous cysts that get bigger and take on odd shapes.

Anyone can have a mucous cyst. But they seem to happen most often in younger adults and children. A strange lump in your mouth might worry you. Or the feeling might bother you. But mucous cysts usually don’t hurt. And, in case you’re wondering, they aren’t a sign of cancer.

What Causes Mucous Cysts?

Mucous cysts in the mouth form in places that are on top of minor salivary glands. Your mouth has hundreds of these glands. They are so tiny that you need a microscope to see them. In those spots, mucus and saliva can leak out into surrounding tissue. That fluid can stay in the tissue in your mouth and form a lump.

It’s often not clear what causes a mucous cyst. They can form if you bite your cheek, tongue, or lip or if you had some other trauma. Sometimes they might happen after a tongue or lip piercing. But people who have a mucous cyst often don’t remember that anything in particular happened before the lump appeared.

How to Get Rid of a Mucous Cyst

Most of the time, mucous cysts go away on their own. They may last for a few days or weeks before they pop. After the cyst ruptures, the spot usually heals.

Some people get multiple mucous cysts. You also can have a mucous cyst that goes away and then comes back. You don’t have to do anything about it. But if you have a mucous cyst that is painful or causing you trouble, a doctor can treat it. 

Possible treatments include:

The best way for you to get rid of a mucous cyst for good is to remove it with surgery. The doctor will also remove the minor salivary gland that keeps causing the cyst. That way, the problem can’t recur.

Is Mucous Cyst Dangerous?

In some cases, bacteria in a mucous cyst may cause an infection. 

See your doctor if:

  • You think you have an infection.
  • You have pain or bleeding.
  • You aren’t sure that what you’ve got is a mucous cyst.

A dermatologist can take a biopsy of your lump to make sure it’s really a harmless cyst and not something else.

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