Common Causes of Armpit Pain
Pain under the armpit, also known as axillary pain, is a common symptom with a wide range of potential causes. In many cases, the source is relatively benign and resolves on its own. However, the symptom should not be ignored, as it can occasionally signal a more serious underlying health issue. This section details some of the most frequent culprits behind underarm discomfort.
Musculoskeletal Issues
One of the most straightforward explanations for armpit pain is related to the muscles, joints, and nerves in the area. The armpit is a nexus of several important structures, and injury can cause significant pain.
- Muscle Strains: Overexertion or injury to muscles in the chest (pectoralis major), upper arm (coracobrachialis), or shoulder can cause a strain, with the pain radiating to the armpit. This can happen from weightlifting, sports like tennis, or even lifting heavy boxes. Rest, ice, and gentle stretching can often resolve this type of pain.
- Nerve Irritation: Nerves running through the shoulder and chest, including the axillary nerve, can become pinched or irritated. This can result in a sharp, shooting, or radiating pain. It might be triggered by an injury, improper use of crutches, or long-term pressure on the area.
- Axillary Web Syndrome (AWS): This condition can occur after breast cancer surgery and involves the formation of tight, painful bands of tissue under the skin of the armpit. Movement often exacerbates the pain.
Swollen Lymph Nodes (Lymphadenopathy)
The armpit contains a high concentration of lymph nodes, which play a crucial role in the immune system by filtering toxins and fighting infection. Swelling of these nodes is a common cause of pain and can indicate various conditions.
- Infections: When the body is fighting an infection, such as a cold, the flu, or strep throat, the lymph nodes can swell and become tender. This is a normal part of the immune response and usually subsides once the infection clears.
- Skin Infections: Localized infections in the armpit, such as cellulitis, folliculitis (inflamed hair follicles), or hidradenitis suppurativa (a chronic skin condition), can cause nearby lymph nodes to swell.
- Autoimmune Disorders: Conditions like rheumatoid arthritis and lupus can cause generalized lymph node swelling.
- Cancer: Though less common, persistent and painless swelling of lymph nodes can be a sign of certain cancers, including lymphoma or breast cancer.
Skin Conditions and Irritations
Given the armpit's moist environment, it is susceptible to various skin issues that can cause pain.
- Contact Dermatitis: An allergic reaction to products like deodorant, soap, laundry detergent, or lotions can cause a painful, itchy, and red rash.
- Fungal or Bacterial Infections: Warm, damp areas like the armpit are prone to infections such as ringworm or erythrasma, which can cause discomfort and rashes.
- Ingrown Hairs: Shaving can sometimes lead to ingrown hairs, which can become infected and form painful, red bumps.
- Hidradenitis Suppurativa: This chronic skin condition involves painful, deep bumps or boils forming where skin rubs together, a condition known to affect the armpit.
Less Common but Serious Conditions
In rarer cases, armpit pain can be a symptom of more serious health problems.
- Heart Conditions: Angina or a heart attack can sometimes cause pain in the armpit, along with chest pain and other symptoms. This is especially true if the pain radiates down the left arm.
- Breast Cancer: Though a painless lump is a more classic sign, some types of breast cancer can cause armpit swelling and pain, particularly if cancer cells have spread to the lymph nodes.
- Sarcoma: This rare form of soft tissue cancer can sometimes present as a fast-growing, painful lump in the armpit.
Armpit Pain: Conditions Comparison
| Feature | Muscle Strain | Swollen Lymph Nodes | Contact Dermatitis | Hidradenitis Suppurativa |
|---|---|---|---|---|
| Sensation | Sharp or dull ache, worsens with movement | Tender, painful, firm lump | Itchy, red, burning rash | Painful, deep, boil-like bumps |
| Associated Symptoms | Stiffness, reduced range of motion, potential bruising | Fever, sore throat, fatigue, localized infection | Blisters, skin dryness, peeling | Sinus tracts, scarring, potential odor |
| Primary Cause | Overexertion or injury to chest/arm muscles | Response to infection, inflammation, or disease | Allergic reaction to products | Clogged hair follicles |
| Treatment Approach | Rest, ice, over-the-counter pain relief | Treat underlying infection (e.g., antibiotics), rest | Identify and avoid irritant, topical creams | Medications, hygiene, potentially surgery |
When to Seek Medical Attention
While many causes of armpit pain are minor, some situations warrant prompt medical evaluation to ensure proper diagnosis and treatment. You should contact a healthcare provider if you experience any of the following:
- The pain is severe or persists for more than a couple of weeks.
- You discover a new or growing lump in your armpit, breast, or collarbone area.
- You have a fever, night sweats, or unexplained weight loss.
- The pain is accompanied by swelling, redness, or signs of infection.
- You experience symptoms related to a heart condition, such as chest pain, shortness of breath, dizziness, or pain radiating down your arm.
- The pain significantly interferes with your daily activities.
Diagnostic Process and Treatment
A doctor will typically begin by taking a detailed medical history and performing a physical examination. This may involve checking the lymph nodes, breasts, and surrounding muscles to identify potential sources of the pain. Depending on the findings, further tests may be ordered to confirm a diagnosis.
- Blood tests: Can help identify infections or underlying systemic conditions.
- Imaging studies: An ultrasound, MRI, or mammogram might be used to get a clearer picture of the tissues in the armpit and breast.
- Biopsy: If a suspicious lump is found, a tissue sample may be taken for laboratory analysis.
Treatment plans vary widely based on the underlying cause. Simple muscle strains may only require rest, cold compresses, and over-the-counter anti-inflammatories. Bacterial infections often require a course of antibiotics, while skin rashes might be treated with topical creams. For more complex conditions like cancer, treatment would involve specialized care from oncologists and surgeons. For ongoing conditions, such as hidradenitis suppurativa, management might involve a combination of medication and lifestyle adjustments.
Conclusion
Pain under the armpit can be an uncomfortable and sometimes worrying symptom. While it is most frequently caused by minor issues like muscle strains, irritation, or temporary swollen lymph nodes from an infection, understanding the full range of potential causes is important. By paying attention to the specific characteristics of the pain and any accompanying symptoms, you can better determine when home remedies are sufficient and when it is time to consult a healthcare professional. A timely and accurate diagnosis is key to both resolving the immediate discomfort and addressing any serious underlying conditions. For more information on health conditions, consult the U.S. National Library of Medicine.
