Six common summer rashes — and how to treat them

Although the current warmer weather is a great mood booster, the combination of heat, sweat and friction creates the perfect environment for a number of common skin rashes.

Dr. Alison Grimston, GP and functional medicine doctor, highlights the symptoms and causes of six common summer rashes, and shares treatment options.

1. Heat rash

“Heat rash is related to blocked sweat ducts, which cause small, itchy red bumps that are usually on the neck, chest, and back,” says Grimston. “The best way to manage a heat rash is to keep cool, wear loose clothing, and have cool showers. It should usually settle on its own.”

2. Polymorphic light eruption

People often mistake polymorphic light eruption for heat rash, because both cause itchy, red bumps, but they are triggered by different things.

“Some people have a sun allergy, called polymorphic light eruption,” says Grimston. “This often appears when you go on your first sunny holiday or in spring or early summer.” The rash may have small, raised spots or blisters, have larger blotchy areas, be itchy, or feel like it’s burning, and be red or pink.

“It usually occurs on the chest, arms, and shoulders; anywhere that’s exposed to the sun,” says Grimston.

SPF creams and gradual sun exposure are the best ways to prevent it.

3. Contact dermatitis

Contact dermatitis is a type of eczema triggered by contact with a particular substance.

“Summer triggers can include sunscreens, fragrances, and chemicals in a swimming pool,” says Grimston.

Symptoms can range from mild redness and itchiness of the skin to skin that becomes cracked, filled with fluid, extremely itchy, and has a stinging sensation.

It usually improves or clears up if the substance causing the problem is identified and avoided.

“Read the ingredients on sunscreens and try to use as natural a sunscreen as possible,” says Grimston. “Emollients can also help, and sometimes you might need a mild steroid cream to help it to settle.”

4. Insect bites

“Warmer weather means more time outdoors, exposing us to mosquitoes, midges, horseflies, wasps, and bees,” says Grimston. “Insect bites usually present in a raised, red, itchy bump that has local swelling and warmth around the bite, and occasionally blistering.” The GP recommends washing an insect bite with soap and water and applying a cold compress for 10-20 minutes. “Avoid scratching, as that can damage the skin and increase the risk of secondary infection,” she adds. “Oral antihistamines can help, if itching is troublesome, and a mild, topical hydrocortisone cream, that you can buy over the counter, can help reduce inflammation.”

5. Swimmer’s itch

“Swimmer’s itch, which is also called cercarial dermatitis, is an allergic skin reaction caused by tiny parasites, called cercariae, released by certain freshwater snails,” says Grimston. “These parasites normally infect birds and can’t survive in humans, but they can penetrate the outer layer of the skin and trigger an immune response.

“Symptoms include tingling or burning shortly after leaving the water, itchy red spots, or small raised bumps, and, occasionally, tiny blisters. It usually develops within hours and settles over several days.” Shower after swimming, towel drying vigorously after leaving fresh water. Avoid affected lakes.

“Treatment options include cool compresses, emollients to soothe the skin, oral antihistamines for the itch, and a mild, topical steroid cream, if needed,” says Grimston.

6. Intertrigo

“With intertrigo, inflammation develops when skin rubs against skin,” says Grimston. “It’s common under the breasts, in the groin, and between abdominal folds. It can also occur in the armpits, between the buttocks, between the toes, and even inside the belly button.” Summer conditions make it worse.

“In the summer, you’ve got heat, sweating, friction, plus reduced airflow, and that damages the skin barrier, especially if it’s staying damp,” says Grimston.

“This can lead to candida overgrowth, which is the fungus that causes thrush, and it can also cause proliferation of bacteria, so you can often get a secondary bacterial infection where it gets even worse.”

“Symptoms include red rash, burning, itching, or soreness, and occasionally you can get a cracking,” adds Grimston. “If there’s a secondary bacterial infection, you may get an unpleasant smell.”

Keep the affected area cool, clean, and dry. “You need to wear loose cotton clothes, where possible, and dry carefully after showering,” says Grimston. “I usually recommend topical antifungal cream, such as Daktarin. If there’s a bacterial infection, you may need antibiotics. If a rash is spreading, is very painful, is associated with fever, or simply isn’t improving after a week or two, seek medical advice rather than just trying another cream.

“The skin likes to be clean, cool, and dry and treating the underlying cause is just as important as treating the rash. If a rash keeps coming back, it’s worth asking whether there’s an underlying condition, such as diabetes, pre-diabetes, or eczema.”