Armpit impetigo: recognition, treatment and spread prevention

It can begin where rubbing, shaving or scratching has broken the skin. Sores or small blisters may leak and form yellow-brown crusts. Because several underarm rashes can look alike, a clinician should confirm the diagnosis rather than relying on appearance alone.

Impetigo develops when bacteria enter the surface of damaged skin. Warmth, moisture and close skin contact can help the infection spread across the fold or to another person. Atopic dermatitis, scratching and minor shaving injuries can weaken the skin barrier and create entry points.

Crusting is a common presentation of impetigo, but crusted skin can have other causes. A clinician looks at the type of sore, its distribution and signs of deeper infection. A sample may be considered when the diagnosis is uncertain, infection returns or initial treatment does not work.

Contact a healthcare professional for diagnosis and treatment. Use prescribed antibiotic medicine exactly as directed and complete the course unless the prescriber changes the plan. Gently wash the area, pat it dry and avoid shaving, picking crusts or applying cosmetic products to open sores.

Wash hands after touching the area and keep personal towels, razors, clothing and deodorant separate. Launder items that contact the rash and cover weeping sores with a clean dressing if advised. Do not share leftover antibiotics, because the appropriate medicine depends on the infection and the person.

Seek prompt medical review if redness spreads, pain or swelling increases, pus accumulates, fever develops or red streaks extend from the armpit. Urgent care is appropriate if the person seems very unwell or the swelling affects arm movement. Reassessment is also needed when prescribed treatment is not improving the rash or new sores continue to appear.

Ask whether the rash is impetigo or another fold condition, whether medicine should be applied or taken by mouth, and how to dress the area. Confirm when close-contact activities can resume, what hygiene measures household members need and which changes would mean the infection is spreading.