Skin Problems Image Gallery
Skin Problems Image Gallery

Men should be especially vigilant, since they are twice as likely as women to develop underarm cysts.

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Finding unexpected lumps anywhere on the body can be an unnerving, and potentially scary, development. If those lumps are underarm cysts, the problem generally is more annoying than dangerous.

An underarm cyst is typically a sac beneath the skin containing pus, like a pimple. They often result from a hair follicle or an oil-producing gland within the follicle becoming damaged.

On your face, acne can be responsible. In your underarms, shaving might be to blame. But any kind of damage to the skin, such as a wound or exposure to ultraviolet rays, can create conditions that result in a cyst.

Once a cyst starts growing, it fills 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.

When it comes to diagnosing underarm cysts, consider that not all underarm lumps are cysts. It could be a swollen or irritated lymph node (glands that help your body fight infection). Although the only sure way to diagnose a lump under your arm is to have a doctor inspect it, there are basic symptoms to look for. Cysts are usually skin-colored, and unless infected, should be painless. They tend to be small growths, and generally don't get much larger than 2 inches (5 centimeters) across.

You can also check a growth by squeezing the lump between thumb and forefinger, and move it back and forth. If it wiggles, it's probably a cyst. Another good indicator that the growth is benign is whether you've recently injured the skin near the cyst. Acne, shaving and even antiperspirants can all cause the irritation and skin damage leading to a cyst.

Underarm Cyst Treatment Options: Good hygiene and washing regularly is a great way to care for your skin. Unfortunately, there isn't much preventive care for cysts. If one develops, you have several courses of treatment:

  • Be a patient patient: First, quite simply, is no treatment at all, since cysts are usually not harmful or painful. You might be tempted to pop it like a pimple. Don't. This can damage the skin and might lead to infection or scarring. Plus, it doesn't guarantee that the cyst won't return.
  • Throw in the towel: Another option is to apply a warm, wet towel to the cyst, which might help clear it up. But if you develop a cyst and it bothers you for cosmetic reasons -- or worse, if it becomes infected, inflamed or painful -- you should see your doctor.
  • Call a pro: Doctors have several treatment options. If the cyst is inflamed, it can be injected with steroids to reduce the swelling before treating it further.
  • Down the drain: Your doctor might drain the pus. This, however, leaves the cyst intact, allowing for the possibility of it returning.
  • It's called a laser: To remove the cyst completely, the doctor can do an 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. If all else fails, your doctor might use a laser to vaporize the cyst.

All of these various treatments are in-office procedures, and don't require a hospital stay. At most, they will require local anesthesia -- and possibly a few stitches. To learn more about cysts and other types of underarm lumps, visit the links on the following page.