[40F] Concern about a red bump in the underarm

What might be happening

Based on your description, here are some possible causes for the red bump in your underarm:

• Folliculitis: This is an infection of the hair follicles, the tiny pockets from which each hair grows. It can be caused by bacteria, such as Staphylococcus, or fungi. Folliculitis is often associated with red, tender bumps, sometimes with a white head.

  • Treatment typically involves topical antibiotics, warm compresses, and good hygiene.

• Hidradenitis Suppurativa: This is a chronic skin condition that features pea- to marble-sized lumps under the skin. They are usually painful and may break open and drain foul-smelling pus. In many cases, they are persistent or recurrent.

  • Treatment often involves antibiotics, corticosteroids, hormonal therapy, and sometimes surgery.

• Lymphadenopathy: This refers to enlarged lymph nodes, which can be a sign of an infection or, less commonly, a malignancy. They are usually soft or firm, round, and movable, and they can be tender.

  • Treatment depends on the underlying cause, which can range from wait-and-see for simple infections, to antibiotics, to more serious interventions.

• Cyst or Abscess: These are fluid- or pus-filled pockets under the skin, which can be caused by infection, clogging of sebaceous glands, or foreign bodies. They can be red, warm, and tender.

  • Treatment usually involves draining the fluid and may include antibiotics.

What you can do

• Apply a warm compress to the area 3-4 times a day for 15-20 minutes at a time. This can help reduce inflammation and pain.
• Keep the area clean and avoid squeezing or scratching the bump, as this can lead to further inflammation or infection.
• Over-the-counter pain relievers, such as ibuprofen, can help with pain and inflammation.
• If the bump does not improve or worsens over the next few days, seek medical attention.

What you should look out for

• If the bump grows rapidly in size, becomes significantly more painful, or starts draining pus, seek medical attention immediately.
• If you develop a fever, chills, or feel generally unwell, these could be signs of a more serious infection requiring immediate medical attention.
• If you notice similar bumps appearing in other areas, this could indicate a more widespread issue that needs medical evaluation.

Remember, I'm an AI and this advice is based on the information you've given me. It's always a good idea to consult with a healthcare professional who can evaluate your symptoms in person.