A tailbone cyst is a fluid-filled sac in the crease between the buttocks, near the tailbone. It often contains hair and small pieces of skin. It can get infected and cause an abscess, which is a pocket of pus. Pus is a thick fluid that usually contains white blood cells, dead tissue, and germs.
A tailbone cyst is also called a pilonidal cyst.
What is the cause?
These cysts are often caused by an ingrown hair (hair that grows under the skin instead of on top of the skin). Ingrown hairs happen, for example, because of pressure or friction from tight clothes, sitting, or riding a bicycle for a long time. The ingrown hair irritates the tissue under the skin and causes a cyst to form around the hair.
You may be more likely to have a pilonidal cyst if you were born with a little dimple in the skin between the buttocks.
What are the symptoms?
Symptoms may include:
Pain when you sit
Redness and swelling in the area of your tailbone in or just above the crease between your buttocks
Pus oozing from the swollen area
Tenderness when the swollen area is touched
Rarely fever, weakness, or nausea
The size of the pilonidal cyst may range from a small tender dimple to a large painful area.
How is it diagnosed?
Your healthcare provider will ask about your symptoms and medical history and examine you.
How is it treated?
You should not try open or squeeze a cyst yourself. This can make the infection worse or cause it to spread.
If there is no infection, your healthcare provider may remove the hair around the cyst and remove any ingrown hair.
If the cyst gets infected, usually it needs to be drained by your healthcare provider. This treats the infection and gets rid of the pressure that causes pain. Even if the cyst is not infected, opening it and draining it is recommended to relieve pain and prevent infection. In some cases your provider may remove the whole cyst. A pilonidal cyst can return after treatment.
Your provider will discuss your choices for treatment.
How can I take care of myself?
Before you see your healthcare provider for treatment, it can help to:
Soak in a tub of warm water for 10 to 15 minutes, several times a day, to lessen pain. Sometimes the cyst may open on its own.
Keep the area clean and dry.
Take nonprescription pain medicine to relieve pain.
After the cyst is drained, make sure that you follow all of your healthcare provider’s instructions.
Ask your provider:
How long it will take to recover
If there are activities you should avoid and when you can return to your normal activities
How to take care of yourself at home
What symptoms or problems you should watch for and what to do if you have them
Make sure you know when you should come back for a checkup. Keep all appointments for provider visits or tests.
How can I help prevent a pilonidal cyst?
To help prevent another cyst:
Keep the area between the buttocks dry and clean.
Keep hair out of the area by shaving or using a hair removal cream.
Adult Advisor 2015.1 published by RelayHealth. Last modified: 2014-07-23 Last reviewed: 2014-07-23
This content is reviewed periodically and is subject to change as new health information becomes available. The information is intended to inform and educate and is not a replacement for medical evaluation, advice, diagnosis or treatment by a healthcare professional.