Prickly heat in the armpit: what to know

The armpit is a warm fold where sweat, deodorant, clothing, and skin-to-skin rubbing can reduce airflow. Heat rash, also called prickly heat or miliaria, may cause tiny raised spots, redness, stinging, or itch. The appearance can be subtle in darker skin tones, so texture and prickling matter as well as colour. Similar-looking [Skin Bumps](/symptoms/skin-bumps/) or [Skin Rash](/symptoms/skin-rash/) can have other causes.

Move to a cooler setting, rinse gently with cool or lukewarm water, and pat the area dry. Wear loose, breathable clothing and pause fragranced deodorants or products that sting. Avoid scratching, heavy ointments, and vigorous rubbing, which can hold in moisture. A bland moisturiser may support the skin barrier; see [Emollient Therapy](/treatments/medical-dermatology/emollient-therapy/) for context. Do not use a steroid cream in the fold unless a clinician recommends the product and duration; [Topical Corticosteroids](/treatments/medical-dermatology/topical-corticosteroids/) can be useful for selected inflammation but need careful use in thin or folded skin.

Arrange medical advice if the area becomes increasingly painful, warm, swollen, crusted, wet, or foul-smelling, or if blisters or pus appear. Seek prompt care for fever, rapidly spreading redness, or feeling unwell. If cooling and gentle care do not improve the problem, a clinician can distinguish heat rash from infection, contact dermatitis, or another cause of [Skin Redness](/symptoms/skin-redness/).

Could this be heat rash or a reaction to my deodorant? Which products are suitable for an armpit fold? Should I stop any current cream, and what changes would mean I need a review?