Discovering a lump in your armpit can be alarming. An armpit lump, or axillary mass, can stem from a wide variety of causes, ranging from benign skin issues to more significant medical conditions. Since the treatment depends entirely on the underlying cause, self-diagnosis is not advisable. A professional medical evaluation is necessary to accurately identify the source and determine the appropriate course of action.
Common Sources of Armpit Lumps
The most frequent reason for an armpit lump is the swelling of lymph nodes, which are small, bean-shaped structures that are part of the immune system. These nodes enlarge (lymphadenopathy) when filtering infectious agents or abnormal cells. This swelling is often a reaction to a local infection in the arm, chest, or breast area, or a systemic viral illness like the flu or mononucleosis.
Other common causes include various non-cancerous growths and skin issues. A lipoma is a soft, movable, and harmless lump composed of fatty tissue that grows slowly beneath the skin. Cysts are another frequent occurrence, presenting as sacs filled with fluid or pus, such as an epidermal cyst.
Inflammation and infection of the hair follicles or sweat glands can also lead to painful armpit lumps. Folliculitis involves inflammation of the hair follicle, often caused by irritation from shaving or bacterial infection, resulting in small, red, pus-filled bumps. Hidradenitis suppurativa is a chronic inflammatory skin condition that causes painful, deep-seated lumps and abscesses due to the blockage of sweat glands.
Less common, but more serious, causes include tumors like lymphoma, a cancer of the lymphatic system, or the spread of breast cancer to the axillary lymph nodes. Allergic reactions to products like deodorants, medications, or vaccines can also cause temporary lymph node swelling.
When to Consult a Healthcare Provider
Since the cause of an armpit lump cannot be determined by appearance alone, seeking a medical opinion is necessary. Any unexplained lump should be evaluated by a healthcare provider to rule out serious conditions. The initial diagnostic step is a physical examination, where the doctor assesses the lump’s size, texture, and mobility.
There are specific characteristics that signal a need for prompt medical attention. Consult a doctor if the lump does not go away after two weeks or if it gradually becomes enlarged. Lumps that feel hard, are fixed in place, or are painless require immediate evaluation.
Accompanying symptoms also suggest the need for timely assessment. These include a persistent fever, unexplained weight loss, night sweats, or changes in the overlying skin such as redness, warmth, or dimpling. Diagnostic tests, which may include an ultrasound, mammogram, blood count, or a biopsy, will be ordered based on the initial physical exam to determine the precise cause.
Medical Approaches to Removing Armpit Lumps
The medical approach to resolving an armpit lump depends entirely on the diagnosis. For the most common cause—reactive swollen lymph nodes due to a viral infection—no specific treatment is required. The lymph nodes usually shrink back to their normal size once the underlying illness resolves.
If the lump is caused by a bacterial infection, such as an abscess or severe folliculitis, the primary treatment involves a course of oral antibiotics. If the infection is severe, intravenous antibiotics may be necessary. For an abscess (a collection of pus), incision and drainage (I&D) is performed to remove the infected material and promote healing.
Benign growths like lipomas generally do not require treatment unless they grow very large, cause pain by pressing on nerves, or are cosmetically bothersome. If removal is desired, a lipoma can be excised surgically. Cysts may also be drained or surgically removed, especially if they are infected, painful, or tend to recur. Complete surgical excision is necessary to remove the cyst wall and prevent recurrence.
Treatment for chronic inflammatory conditions like hidradenitis suppurativa is often complex and managed by a dermatologist. It can involve topical or oral antibiotics, anti-inflammatory medications, or corticosteroid injections directly into the painful lumps. More advanced or recurrent cases may require surgical removal of the affected tissue.
At-Home Management and Prevention
While a medical diagnosis is necessary, supportive measures can manage discomfort at home, especially for temporary or inflammatory lumps. Applying a warm compress for 10 to 15 minutes, two to three times a day, can help increase blood flow, soften the lump, and provide relief from pain and swelling. Over-the-counter pain relievers, such as ibuprofen, can also be used to ease associated discomfort or inflammation.
It is important to avoid trying to squeeze, pop, or self-drain any armpit lump, as this can force the infection deeper, increase inflammation, and lead to serious complications or scarring. If the lump is caused by an allergic reaction, identifying and discontinuing the use of the triggering product, such as a deodorant, cream, or soap, is necessary for resolution.
Prevention focuses on good hygiene and reducing irritation in the armpit. Keeping the area clean with a mild cleanser and avoiding harsh scrubbing is helpful. Adjusting shaving habits or using different hair removal methods can reduce the likelihood of ingrown hairs and folliculitis. For chronic conditions like hidradenitis suppurativa, avoiding tight clothing and maintaining a clean, dry environment helps manage flare-ups.