What should you know about erythrasma under the breast?

The rash may form a smooth or finely scaly patch in the crease beneath the breast. Colour ranges from pink or red to brown, and itching may be mild or absent. Warmth, sweat, rubbing, and damp fabric can irritate the fold and help bacteria persist. A similar-looking rash can be caused by yeast, contact irritation, or another skin condition, so appearance alone cannot confirm the cause.

A clinician may inspect the border and scale and use a special light or a sample when the diagnosis is uncertain. Mention whether the area smells different, feels sore, cracks, or has been exposed to a new soap, cream, bra, or detergent.

Wash gently, pat the fold dry, and change out of sweaty clothing. A clean, breathable bra and a soft dry layer can reduce rubbing; avoid scrubbing, fragranced products, and steroid cream unless a clinician advises it. Treatment may include [Topical Antibiotic Therapy](/treatments/medical-dermatology/topical-antibiotic-therapy/) when bacteria are responsible. Do not apply antifungal or antibiotic products indefinitely without a diagnosis.

Book an assessment if the patch persists, spreads, repeatedly returns, or becomes uncomfortable. Seek prompt care for rapidly increasing redness, warmth, swelling, pus, open cracks, fever, or feeling unwell. These features can indicate a deeper infection or significant skin breakdown.

Ask what features distinguish erythrasma from yeast or dermatitis, whether testing is useful, how long to use the recommended treatment, and how to keep the fold dry without damaging the skin.