Right-side pain under the armpit may be due to muscle strain, infections, or skin conditions. Sometimes, armpit pain may indicate a more serious issue, such as cancer or an issue with the heart.

The armpit area contains many lymph nodes, nerves, and blood vessels. It also connects to muscles in the chest, arms, and around the rib cage.

There are many causes of right-side pain under the armpit, including muscle strain, infections, or skin conditions. In some cases, it may indicate a more severe condition, such as cancer.

This article examines the possible causes of right-side pain under the armpit, treatment options, and when to contact a doctor.

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Pain under the armpit can have various causes, including:

Muscle strain

Injury to the pectoral muscles in the chest area may cause pain under the armpit. A strain or injury may occur through muscle overuse through physical activity such as weightlifting.

People may experience:

  • limited range of motion
  • pain
  • weakness
  • swelling
  • bruising
  • tenderness

In rare cases, people may experience a tear in the pectoral muscles. People may experience a tearing or a popping sound before the symptoms above develop.

Learn more about muscle strain.

Swollen lymph nodes

The armpit consists of around 20–30 lymph nodes. Swollen lymph nodes may cause pain under the armpit. Possible causes of swollen lymph nodes include:

Learn more about swollen lymph nodes.

Skin conditions

Certain skin conditions, such as contact dermatitis, may cause irritation, blisters, and itching to the underarm. Contact dermatitis may occur due to irritants, such as deodorants, body washes, or fragrances.

Inverse psoriasis is a type of psoriasis that commonly affects the armpits and may cause pain and irritation.

Learn more about inverse psoriasis.


Intertrigo may cause a rash under the arms due to inflammation or infection. Intertrigo may cause the skin under the arm to feel inflamed and uncomfortable.

In some cases, intertrigo may be due to bacterial or fungal infections. If a rash only affects the right underarm, it may be an infection, as these more commonly affect one armpit rather than both.

Learn more about intertrigo.


A lipoma is a noncancerous lump of fat tissue that forms under the skin and feels rubbery.

Lipomas can occur in under the armpit, although this is rare. More commonly, they affect the shoulders, arms, or upper back.

Learn more about lipomas.


Shingles is a rash on one side of the body that feels painful and may affect the area under the armpit. Symptoms include:

  • pain, tingling, or itching before a rash appears
  • rash with blisters
  • fever
  • chills
  • headache
  • upset stomach

Learn more about shingles.

Swelling or lumps under the armpit may be a sign of certain cancers, including lymphoma, leukemia, or breast cancer that has spread to lymph nodes in the armpit area.

Swollen lymph nodes are usually due to a cause other than cancer, but it is important to consult a doctor to determine the underlying cause.

Learn more about lymphoma.

Short-lived pain under the armpit alongside chest pain may indicate angina.

Angina is a heart condition that occurs when the heart does not receive as much blood as it requires. This may be due to coronary heart disease.

People may feel pressure or discomfort in the center of the chest that spreads to the underarms, back, arm, neck, or jaw. This pain may last for around 5 minutes and ease with rest or medication.

Pain radiating from the chest to one or both arms may be a warning sign of a heart attack. While this pain usually affects the left arm, it can also affect the right. Signs to be aware of include:

Learn how to spot and treat a heart attack.

People should contact a doctor if they have:

  • swelling or a lump under the arm
  • underarm pain that does not go away
  • signs of shingles
  • infection that does not resolve with home treatments

People must seek emergency medical attention if they have:

  • chest pain or discomfort
  • pain in the upper body
  • shortness of breath
  • nausea or vomiting
  • lightheadedness

To determine the cause of pain under the armpit, a doctor may take a medical history, perform a physical exam, and examine any symptoms. A doctor may also perform certain tests to find out the underlying cause, such as:

  • taking a swab to check for bacterial or fungal infection
  • skin or tissue biopsy
  • scans, such as MRI, CT, or X-ray
  • testing strength and range of motion of the arm in case of injury
  • blood tests to test for autoimmune conditions

Depending on the underlying cause, people may be able to treat some types of underarm pain with simple steps and home remedies, such as:

  • applying a warm or cold compress to the area
  • over-the-counter pain relief or anti-inflammatory medications
  • massaging the area
  • using topical creams to treat a skin condition, such as topical antifungals, antibiotics, or steroids
  • keeping the armpits clean to avoid infections
  • using a clean razor when shaving and avoiding sharing razor blades
  • wearing loose-fitting clothing to prevent chafing
  • avoiding irritants in body washes and deodorants
  • resting and avoiding strenuous activity if someone has a strain
  • using antiperspirants to reduce sweating
  • drying the underarms properly to prevent a moist environment

The outlook for pain under the armpit may depend on the underlying cause and other factors, such as a person’s age and overall health.

Infections, skin conditions, and muscle strain may resolve easily with treatment and rest. People will require specialist treatment if underarm pain is due to cancer or heart issues.

Right-side underarm pain may occur for various reasons, such as muscle strain, skin conditions, or infections. In some cases, underarm pain may indicate a serious condition such as cancer or heart issues.

Treatment will depend on the underlying cause, but in some cases, home remedies may help to resolve the issue.

If people experience persistent pain, swelling, or lumps under the arm, they should consult a doctor. Anyone with chest pain alongside underarm pain needs to seek medical help immediately.