Pilonidal Cyst (Not Infected)
A pilonidal cyst is a fluid-filled sac that starts under the skin on the sacrum near the tailbone. It may look like a small dimple. It can fill with skin oils, hair, and dead skin cells, and it may stay small or grow larger. Because it often has an opening to the surface, it may become infected with normal skin bacteria.
Causes
The cause of pilonidal cysts has been debated since they were first recognized. It may be present at birth and go unnoticed. Injury, rubbing, or skin irritation may also cause pilonidal cysts. It can also be caused by an ingrown hair. Most likely, the cause may be a mix of these things. Some injury or irritation can lead to pilonidal cysts. So they can be more common in people who sit or drive a lot for work.
Symptoms
A pilonidal cyst may be small and painless. If symptoms occur, they may include:
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Swelling.
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Irritation or redness.
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Pain.
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Drainage.
The cyst can swell and drain on its own. The swelling and drainage can come and go.
Treatment
If a pilonidal cyst isn't infected or causing problems, you may not need treatment beyond home care. In some cases, hair removal by shaving or laser treatment may be advised. Talk with your doctor about your specific situation and if this is advised. It's not clear if hair removal is helpful in people with no symptoms.
If the cyst comes and goes, is bothering you, or becomes infected, you'll need medical care. You may need surgery to fix it.
Home care
These guidelines will help you care for your cyst at home:
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Keep the area of the cyst clean by bathing or showering every day.
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Don't wear tight-fitting clothing over the cyst.
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Don't try to squeeze the cyst or stick a needle in it to make it drain. It may feel better at first. But it will make it worse and likely cause infection.
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Watch for signs of infection listed below.
Follow-up care
Follow up with your doctor as advised.
When to contact your doctor
Contact your doctor right away if:
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Pus is coming from the cyst.
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You have increasing local pain, redness or swelling.
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You have a fever of 100.4°F (38.0°C) or higher, or as advised by your doctor.
Online Medical Reviewer:
Daphne Pierce-Smith RN MSN
Online Medical Reviewer:
Melinda Murray Ratini DO
Online Medical Reviewer:
Rajadurai Samnishanth Researcher
Date Last Reviewed:
5/1/2025
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