How to Treat an Underarm Cyst

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Skin Problems Image Gallery Underarm cysts are usually more of an annoyance than a health hazard. See more pictures of skin problems.
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Finding lumps anywhere on the body can be a potentially scary development, but if those lumps are underarm cysts, the problem generally is more annoying than dangerous to your health. The term "cyst" actually comes from the Greek word "kystus," which means "bladder" [source: University of Rochester]. In this case, the term bladder just refers to a sac -- particularly a sac beneath the skin containing pus, much like a common pimple [source: MedlinePlus: Sebaceous].

This sac forms when some of your epidermal skin cells don't slough off, but instead move down under the surface of your skin and begin to grow there. This often happens as a result of a hair follicle or an oil-producing sebaceous gland within the follicle becoming damaged [source: Mayo Clinic]. On your face, for example, acne might cause such damage. In your underarms, shaving might be to blame. But any kind of damage to the skin, such as a wound or exposure to harmful ultraviolet rays, can create the conditions that form a cyst [source: Mayo Clinic]. Even being a male raises your chances of getting one, because men are twice as likely as women to develop cysts [source: Hanson].


Once the cyst starts to grow, it forms a small sac that fills up with a protein called keratin that has a yellowish color and foul odor. This sac grows to create a small protrusion on your skin at the source of the initial injury [source: MedlinePlus: Sebaceous].

Although the armpits are a sensitive area of the skin, most cysts are harmless, painless and can actually be left untreated. But if you develop a cyst and it bothers you for cosmetic reasons, or worse, if it becomes infected, you should see your doctor.

Read on to discover ways of diagnosing and treating underarm cysts.


Diagnosing Underarm Cysts

Any lump that appears on the body with no explanation is an unwelcome intruder. Plus, not knowing what to do if one takes shape under your arm can be irritating physically and mentally. Although the only sure way to diagnose a lump under your arm is to see your doctor and have it tested, there are some basic symptoms to look for that will help you determine whether the lump in question is a cyst.

Cysts are usually skin-colored, perhaps with a yellowish tint, and unless they are infected, they should be painless. They tend to be small growths, not getting much larger than 2 inches (about 5 centimeters) across. Some cysts exhibit either a blackhead or evidence of a skin pore that if squeezed or accidentally ruptured, will leak a cheese-textured and foul-smelling pus [source: Mayo Clinic].


Another way to check the cyst is to do the wiggle test. Take your thumb and forefinger, gently squeeze the lump and then move it back and forth. If it wiggles, that is an indication that it's probably a cyst because they tend to be easily movable [source: University of Rochester].

If you've recently experienced some sort of skin injury at or near the site of the cyst, that is also a good indicator that you are dealing with a benign growth. Acne, shaving, and even antiperspirants (not deodorant) can all cause the irritation and skin damage that leads to the formation of a cyst [source: MedlinePlus: Armpit].

If the cyst is not causing any pain or discomfort physically or psychologically, it can be left alone. However, if you are worried it is more than a cyst, or if the cyst ruptures or becomes infected, inflamed or painful, then treatment options -- described in the next section -- are available.


Underarm Cyst Treatment Options

Unfortunately, there is not much preventive care for cysts. Good hygiene, washing regularly and taking care of your skin is the basic regimen to keep up. So if one does develop, despite your squeaky clean skin, there are a few courses of treatment you can pursue [source: Mayo Clinic].

One treatment is no treatment at all, since cysts are usually not harmful or painful. And though it might be tempting to take care of it on your own by popping it like a pimple, this is not recommended -- for cysts or for pimples -- because it damages the skin and might lead to infection or scarring. Plus it doesn't guarantee that the cyst won't return [source: Mayo Clinic].


If you're not ready to see a doctor, but want to try something, applying a warm, wet towel to the cyst might help in clearing it up [source: MedlinePlus: Sebaceous]. But if it doesn't, and you really want it gone, see your doctor. He or she will have a number of treatments that should be able to clear it up. If it is inflamed, it can be injected it with steroids to reduce the swelling before treating it further.

Your doctor might simply drain the pus, although this leaves the cyst intact and allows for the possibility of its return [source: Mayo Clinic]. To remove the cyst completely, the doctor can do a procedure called excision where he not only drains the pus, but also removes the inner sac -- the lining of the cyst wall -- so that it doesn't grow back [source: American Academy of Family Physicians]. If all else fails, your doctor might use a laser to vaporize the cyst [source: Mayo Clinic].

All of these various treatments are in-office procedures that don't require a hospital stay, and, at most, will require local anesthesia with possibly a few stitches.

To learn more about cysts and other types of underarm lumps, visit the links on the next page.


Lots More Information

Related HowStuffWorks Articles

  • American Academy of Family Physicians. "Minimal Excision Technique for Removal of an Epidermoid Cyst." AAFP. April 1, 2002. (Accessed Sept. 27, 2009)
  • eCureMe. "Sebaceous Cyst." 2003. (Accessed Sept. 27, 2009)
  • Hanson, Linda J. "Epidermal Inclusion Cyst." June 9, 2009. (Accessed Sept. 27, 2009)
  • Mayo Clinic. "Epidermoid Cysts." June 6, 2009. (Accessed Sept. 27, 2009)
  • MedicineNet. "Definition of Axilla." Feb. 15, 2001 (Accessed on Sept. 27, 2009)
  • MedlinePlus. "Armpit Lump." Aug. 2, 2009 (Accessed Sept. 27, 2009)
  • MedlinePlus. "Lymph System." April 13, 2009 (Accessed on Sept. 27, 2009)
  • MedlinePlus "Sebaceous Cyst." April 12, 2007 (Accessed Sept. 27, 2009)
  • Moynihan, Timothy. "Tumor vs. Cyst." Jan. 9, 2009 (Accessed Sept. 27, 2009)
  • University of Rochester Medical Center. Cyst Animation; Dermatology Lexicon Project. (Accessed Sept. 27, 2009)