Cancer4 Common Causes of Armpit Pain

4 Common Causes of Armpit Pain

Armpit pain, referred to medically as axillary pain, can be caused by many different conditions. Whether it’s an aching, sharp, throbbing, or itching sensation, pain in the armpit can be a red flag. Underarm pain can be the result of anything from a simple muscle strain, to more serious conditions such as shingles or certain types of cancers.

Understanding the causes of armpit pain can help you find the best treatment method for your pain. Below are the four most common causes of armpit pain, along with how you can treat them.

Muscle Strains Are the Most Common Cause of Armpit Pain

Muscle Strains Are the Most Common Cause of Armpit PainOne of the most common causes of armpit pain is muscular injuries. Your armpits and the surrounding chest and arm area are made up of hundreds of blood vessels, nerves, and muscles. That said, there is no singular muscle found in the underarm. This means that armpit pain due to a muscle strain will typically be the result of a muscle found outside of the armpit such as the shoulder or bicep. Muscle strains in this area can cause mild to severe armpit pain and may take several weeks to heal.

Since the anatomy of the armpit is very complex, several major muscle groups meet in the armpit. This can make it difficult to determine what the cause of your armpit pain may be. Some of the most common muscles that can cause armpit pain if strained are:

  • Infraspinatus: The rotator cuff muscle that helps with raising and lowering the arm
  • Triceps brachii: Commonly known as the tricep, this is the large muscle in the back of the upper arm. The triceps help with straightening the arm.
  • Pectoralis major and minor: These are the two muscles associated with the chest area. They stretch from the armpit up to the collarbone and down across the chest area.
  • Teres Major: This muscle is found in the upper back, and helps rotate the upper arm.
  • Biceps brachii: Known as the bicep, this muscle is found at the top of the humorous bone, and runs up to the armpit. It is used to help rotate the forearm and also flex the elbow.
  • Latissimus dorsi: This flat rectangular muscle of the back helps the arms rotate as well as move away and closer to the body.
  • Supraspinatus: This small muscle is located at the top of the shoulder and helps raise the arm away from the body.

Like other muscles in your body, you can strain these armpit muscles by overexerting or hyperextending your arms while doing things like lifting heavy weights or bracing for a fall. Typically, the symptoms of a muscle strain depend on how serious the injury is. That said, some standard signs of a muscle strain in the armpit include:

  • Armpit pain or tenderness, especially after the movement that stretches the muscle
  • Redness or bruising in the underarm
  • Muscles spasms or twitching
  • Swelling

Armpit pain can be especially difficult to live with, as we are constantly using the muscles that are found in and around it. Muscle strains in the armpit can be treated exactly like strains found elsewhere in the body.

How to Treat Muscle Strains in the Armpit

For more mild muscle strains, most doctors suggest that you rest the muscle by taking a break from whatever activity may have caused the pain. Immediately after injury, putting ice on the area can help reduce pain and the initial swelling that follows an injury. You can also take some over-the-counter medicines such as ibuprofen or aspirin to help with pain and inflammation.

For more severe muscle strains, contact your doctor if your symptoms get worse, or your armpit pain doesn’t subside within a few weeks.

Armpit Pain Can Also Be Caused by Swollen Lymph Nodes

Another common cause of armpit pain is swollen lymph nodes. Lymph nodes are found in many different parts of the body, including your neck, groin, and armpits. These small bean-shaped structures are part of the immune system and help with fighting infections and diseases. When lymph nodes become swollen, they can be extremely painful and are typically a sign that your body is fighting a viral infection. Some of those infections can include:

  • The common cold
  • Strep throat
  • Measles
  • Mononucleosis, a contagious infection caused by a herpes virus called Epstein-Barr.
  • An ear or tooth infection

Recently, there has been vaccines adults to suggest that the lymph nodes in the armpit may become swollen following a COVID-19 vaccination. This typically occurs in the arm where the vaccine was given and is completely normal. The swelling is a sign that your immune system is responding to the vaccine correctly, and will typically run its course in a matter of days to a week.

Treatment for Swollen Lymph Nodes in the Armpit

Treating swollen lymph nodes in the armpit starts by treating the underlying cause. If the swelling is due to an infection, treating it will generally result in reduced swelling and armpit pain. In the meantime, placing a warm, wet washcloth in your armpit can help reduce swelling and pain. You can also take over-the-counter pain medication to help with discomfort. Doctors also recommend you get plenty of rest when dealing with lymph node inflammation.

If your symptoms don’t subside within a few weeks, or if your armpit pain becomes severe, see your doctor to figure out what your next steps should be.

Some Allergens and Skin Irritants Can Cause Discomfort in the Armpit

A less common cause of armpit pain can be allergens and skin irritants. Many deodorants, antiperspirants, body washes, soaps, and laundry products contain skin irritants and allergens. These chemicals can cause allergic reactions such as allergic contact dermatitis, a condition that causes redness and tiny blisters.

Similarly, some skin irritants can also cause discomfort in the underarms. The most common culprits are deodorants and antiperspirants, as they are applied directly to the armpits. Ingredients such as aluminum, found in some antiperspirants, or fragrances in deodorant can cause pain or swelling in the armpits.

Other common causes of underarm irritation include shaving, tight or abrasive clothing, and certain non infectious rashes such as acanthosis nigricans, a velvety rash often found in people who have diabetes or are obese, and psoriasis.

How to Get Rid of Underarm Discomfort

The most obvious way to combat underarm discomfort due to allergens is to simply get rid of the product. However, this can be difficult for many people who may not know what is causing their armpit pain. In these instances, it’s always recommended to see your doctor to figure out if you have any allergies or conditions that may be contributing to your underarm discomfort.

In the meantime, or if you are unable to see a doctor, try switching out the products you use to see if you can determine what may be causing your pain.

Underarm Pain Could Be a Red Flag for Breast Cancer

Underarm Pain Could Be a Red Flag for Breast CancerThe lymph nodes in the chest and armpit can often become overworked and swollen as a result of cancer in the upper body. One such cancer that can cause armpit pain is breast cancer. Breast cancer happens when the cells in the breasts grow uncontrollably. This typically results in tumors, which can become cancerous and spread to other parts of the body.

A common symptom of breast cancer is pain and swelling around your armpit. The swelling and pain may come before you notice any lumps in your breast, which can be a useful warning sign to help catch cancer early.

Other cancers that can cause armpit pain include:

  • Lymphoma
  • Leukemia
  • Lung cancer
  • Melanoma

The most effective way to fight cancer is by detecting it early. It’s important to see your doctor if you notice any abnormal changes in your body, especially if you believe they may be a sign of cancer.

Armpit pain can be caused by mild muscle strains or allergens in your deodorant, but it can also be a red flag for more serious conditions such as breast cancer. Whatever your case may be, it’s always important to listen to your body, and contact your doctor if you notice your condition worsening.

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