What should you know about rash in summer?

Heat and humidity leave sweat on the skin and can block or irritate sweat ducts, producing small itchy bumps. Damp clothing and rubbing can inflame folds. Sunlight can aggravate some existing rashes, while sunscreen, insect repellent or a new laundry product may cause contact dermatitis. A scaly expanding patch may have another cause, such as ringworm. Relevant possibilities include [Heat Rash](/conditions/heat-rash/), [Contact Dermatitis](/conditions/contact-dermatitis/) and [Intertrigo](/conditions/intertrigo/). A summer flare does not identify one diagnosis by itself.

Move to a cool place and rinse sweat away with lukewarm water. Pat dry, wear loose breathable clothing and change damp garments promptly. Keep skin folds dry without vigorous rubbing. Use bland, fragrance-free moisturiser if the skin is dry, and review any new sunscreen, cosmetic or detergent. Avoid scratching, heavy oily layers over heat rash and unprescribed combination creams. If the rash follows sun exposure, cover the area and limit further exposure while arranging advice.

Get urgent help for trouble breathing, swelling of the lips or tongue, faintness, widespread blistering or skin that is peeling. Seek prompt assessment for fever, severe tenderness, pus, rapidly spreading redness or a rash after a new medicine. Make an appointment if the rash keeps returning, spreads despite cooling or does not improve after removing a suspected trigger.

Does the rash fit heat rash, sun sensitivity, eczema, infection or contact dermatitis? Which sunscreen and cleanser should I use? How can I protect skin folds during hot weather? Could any medicine be increasing sun sensitivity?