Head rash: what to know

The scalp, hairline, forehead, or neck can react to products, sweat, friction, or sun. Contact dermatitis may follow a new dye, shampoo, fragrance, adhesive, or styling product. Atopic dermatitis can cause itchy, dry, inflamed skin. Psoriasis may form thicker, well-defined scale, while heat rash tends to appear where sweat and warmth are trapped. Ringworm is a fungal infection that can produce scaling and broken hairs; scabies can cause intense itch and may affect close contacts. A drug rash can begin after a new medicine. These conditions can overlap in appearance, so the distribution, symptoms, exposures, and timing matter.

Stop newly introduced hair or skin products and rinse gently with lukewarm water. Avoid scratching, tight headwear, heat, and heavy fragrance until the skin settles. Do not apply steroid cream, antibiotic cream, or antifungal medicine to an undiagnosed rash without appropriate advice, because the wrong product can mask or worsen some infections. Photograph the rash and note recent products, medicines, illness, travel, and contact with anyone who has a similar itch. A clinician can examine the scalp and decide whether testing or targeted treatment is needed.

Get urgent help for a rash with breathing difficulty, swelling of the lips or face, faintness, blistering, skin peeling, or sores in the mouth or eyes. Seek prompt assessment for fever, pus, severe pain, rapidly spreading redness, or a tender scalp. Arrange a routine review if the rash persists, recurs, causes hair loss, or follows a new medicine.

Ask what pattern the rash suggests, whether a product or medicine could be responsible, whether testing is needed, and which treatment is safe for the scalp and nearby skin.