Armpit Lump

By Ashley Henshaw. May 7th 2016

If you’ve discovered a lump in your armpit, don’t be alarmed. In most cases, the cause is relatively harmless and easy to get rid of. Still, there are potentially serious causes of armpit lumps, so it’s important to always consult your doctor who can further explain whether further tests and treatment are required.


There are several types of lumps that may form on or under the skin due to various causes. These types of armpit lumps include:


The symptoms of armpit lumps vary depending on the type of lump you have:

  • Swollen/enlarged lymph nodes: The lump is located under the skin and is usually tender to the touch.
  • Cysts: The lump may cause the skin to be yellowish in color. The lump rolls around easily under the skin with gentle pressure.
  • Abscesses: The lump may be large and painful. It may form on or under the skin. Those on the skin are usually red in color.
  • Lipomas: Lipomas develop under the skin. They can easily be moved around by placing pressure on the lump.
  • Ingrown hairs: These are very small, tender lumps on the skin affected a particular hair follicle.
  • Tumors: The tumor may be of any size. Some are tender to the touch.

Causes And Risk Factors

A lump in the armpit could be caused by any number of different factors, including:

  • Bacterial infection: An infection in the arm or breast could lead to a lump forming in the armpit. Other infections that may cause an armpit lump include cat scratch disease, lymphadenitis and ascending lymphangitis.
  • Viral infection: Certain viruses can cause a lump to develop in the armpit. Examples include shingles, chickenpox, infectious mononucleosis and AIDS.
  • Fungus: A fungus could also lead to the lump forming. An example is sporotrichosis, which occurs when a fungus found in vegetation comes into contact with broken skin.
  • Irritation: Shaving and the use of antiperspirants may lead to ingrown hairs developing in the armpit area if the skin becomes irritated.
  • Vaccination: Armpit lumps are a side effect of certain vaccinations, such as the vaccine for measles, mumps, rubella, smallpox and typhoid. These side effects are rare and generally go away relatively quickly.
  • Allergic reaction: Having an allergic reaction to a vaccination could also result in a lump forming in the armpit.
  • Growths: Certain types of harmless growths also create armpit lumps. The most common are benign cysts and lipomas. However, normal breast tissue can also grow into the armpit area and create a lumpy feeling in the armpit.
  • Cancer: Certain cancers are related to lumps found in the armpit, including breast cancer, leukemia, Hodgkin’s lymphoma and Non-Hodgkin’s lymphoma.

Few risk factors for armpit lumps exist. Exposure to certain bacteria or viruses could increase your chances of developing armpit lumps if you become infected. Similarly, getting vaccines with a potential side effect of an armpit lump also increases your risk of developing this condition. However, given the small chances of the lump developing, it’s better to get the vaccine than to avoid it.

One area where the risk for armpit lumps may be increased is when an individual has a family history of certain cancers, particularly breast cancer.


Not all types of armpit lumps are preventable, such as cysts and lipomas. However, it is possible to help reduce your chances of developing an armpit lump by avoiding exposure to bacteria, viruses and funguses that may lead to an armpit lump developing. In addition, you can try different products if your lump is caused by shaving or antiperspirant use. You should also get the vaccines recommended by your doctor – they are effective at preventing the viral infections that may cause armpit lumps and rarely cause these lumps to occur as a side effect of being vaccinated.


A doctor will help you determine the best treatment for your armpit lump. The following are some of the most commonly used treatments for various types of armpit lumps:

  • Surgical excision: Lumps that are particularly large, bothersome or malignant may be removed through a small incision in the skin.
  • Tissue sample: A sample of the tissue in the lump may be needed to provide an accurate diagnosis.
  • Cancer treatment: An armpit lump caused by cancer may lead to chemotherapy, radiation or other types of cancer treatment.
  • Draining: Abscesses and certain cysts can be removed by draining fluid from the mass.
  • Antibiotics: An antibiotic may be prescribed if the cause of the lump is a bacterial infection.
  • Vaccination: Some viral infections that cause armpit lumps may be prevented from occurring again in the future by getting a vaccination.

Keep in mind that some types of armpit lumps do not require any treatment. This includes most cysts and lumps caused by normal breast tissue.

See a doctor if you find a lump in your armpit. It’s likely that the cause is benign, but it’s essential to get an accurate diagnosis and to rule out more serious causes before your seek treatment.


More in category

  • Scabies
    Scabies can form in small patches or red bumps, that may cause itching and rashe...
  • Heat Stroke
    Of the 3 types of heat emergencies: heat cramps, heat exhaustion and heat stroke...
  • 3 Ways to Identify a Fire Ant Bite
    Identify the Insect People who suspect they have been bitten by a fire ant shoul...

Related Content