They are filled with a thick, oily substance that may drain out.
Sebaceous cysts can be easily moved under the skin.
It also discusses when sebaceous cyst removal is needed and how it’s done.

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What Is a Cyst?
Acystis a pouch-like tissue sac filled with fluid, air, or semi-solid substances like keratin.
There are many types of cysts.

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Some, like sebaceous cysts, occur underneath the skin.
Others form inside the body, such as on the kidneys or breast.
That can get uncomfortable or painful, especially if they’re inflamed.
Sebaceous cysts can also become inflamed.
If they do, you may notice:
Are Sebaceous Cysts Common?
Sebaceous cysts are not uncommon.
Anyone can get a sebaceous cyst during their lifetime.
What Causes Sebaceous Cysts?
To understand where sebaceous cysts come from, it’s important to understand certain structures in the skin.
Some reasons the sebaceous gland can become blocked include:
What’s Inside a Sebaceous Cyst?
If a sebaceous cyst breaks open, you’ll see keratin ooze out.
It looks pasty or cheesy and may have a foul odor.Infected sebaceous cysts may also be filled with pus.
True sebaceous cysts originate from the outer layer of skin (theepidermis).
Diagnosis
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Many healthcare providers can diagnose sebaceous cysts on sight.
Sometimes, they may order abiopsyor skin culture to rule out similar conditions.
Things that may look like a sebaceous cyst include:
Don’t have a go at diagnose yourself.
See a healthcare provider so you know for sure what it is.
Sebaceous Cyst Treatment
There are no proven or reliable ways to dissolve a sebaceous cyst naturally.
You should never venture to pop or drain a sebaceous cyst yourself, as this can cause infection.
It’s OK if they drain on their own, however.
A sebaceous cyst could resolve within about four weeks or grow or become inflamed or infected.
If a sebaceous cyst is inflamed and bothersome,steroid injectionscan be used to calm and shrink it.
If a sebaceous cyst becomes infected, a healthcare practitioner willopen and drainit using sterile tools.
They may numb the area ahead of time, often with the druglidocaine, to minimize pain.
Infection from a sebaceous cyst can spread to the surrounding skin.
This is calledcellulitis, and it’s a more severe condition.
You may need an oral antibiotic plus incision and drainage.
you’re able to avoid these more severe outcomes by treating infected cysts immediately.
When Surgery Is Needed
Sometimes sebaceous cysts grow large enough to interfere with your daily life.
These may need to be removed.
This is typically performed via a small incision using local anesthesia at the dermatologist’s office.
Your healthcare provider will probably wait until your cyst isn’t inflamed or infected to proceed with surgical removal.
This can keep the cyst from coming back.
You may or may not have stitches that must also be taken out.
How Much Does It Cost to Remove a Sebaceous Cyst?
Summary
Sebaceous cysts are bumps just under the skin full of keratin.
Despite the name, they don’t contain sebum.
They can usually be diagnosed on sight.
Biopsies can rule out similar problems if needed.
Treatments can involve steroid injections, drainage, or surgical removal.
Left untreated, these cysts can become quite large, uncomfortable, or unsightly, which could require surgery.
Getting a sebaceous cyst treated early can prevent the need for surgical intervention.
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