Alarming Reasons Why You Have Pain Under Your Armpit

Some people get scared when they feel a small pain in their armpit. In some cases, this pain happens for a brief moment and disappear immediately. However, sometimes armpit pain may just be a warning sign for a more serious condition.

Here are the possible reasons as to why you are experiencing pain in your armpit.

Skin Irritation and Rashes

Rough fabrics and clothing that are too tight, as well as shaving, can irritate the skin in your armpit, thus leading to pain.

Certain products like lotions, soaps, deodorants, laundry detergents and more can also cause irritation and allergic contact dermatitis.

Some rashes, bumps, and skin issues may just be a symptom of a more serious problem.


Infections cause inflammation and affect the lymph nodes in the armpit leading to pain. Fungal infections such as ringworm and intertrigo can cause a red, itchy rash in the armpit. Shingles, an infection spread by the varicella-zoster virus, can also cause armpit pain.

Peripheral Artery Disease (PAD)

PAD is a common circulatory problem in which narrowed small arteries in the arms and legs reduce oxygenated blood flow to your muscles and tissue limbs. Due to this, the oxygen-starved muscles hurt. You might feel pain in your armpit if you have PAD in one or both arms.

PAD is caused by atherosclerosis, blood clots in the arteries, injury to the limbs, and unusual anatomy of the muscles and ligaments.

Lymph Node Problems

Lymph nodes can be found near the armpit on both sides of the body. The following issues of the lymph nodes may cause armpit pain:

Systemic infection: Mononucleosis, an example of a systemic viral infection, can cause swollen and painful lymph throughout the body, including the armpit.

Lymph node infection: Cuts may cause infections in the lymph nodes of armpit. This may lead to swelling and pain.

Muscle Strain

Several muscles on the arms and chest can cause armpit pain. This may due to injuries while playing sports or lifting weights or being strained from throwing spots such as baseball or form other activities such as badminton or tennis.

Breast Cancer

On its early stages, breast cancer is often painless. Immediately make an appointment with your doctor once you notice pain or feel a lump in your breast or under your arm.

Breast cancer is the last and worst reason why you are experiencing pain in the armpit. When the cancerous tumor in your breast grows, it causes pain in the nearby parts of your body including the armpit. Aside from this, you’ll also experience other symptoms like sore or rash on the nipple, sudden discharge of the breast, and swelling, redness or darkening of the breast.