How to Treat an Underarm Cyst

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.

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.