Causes and Treatments for Summer Rashes

Increased heat, humidity and sun don’t do your skin any favors in the summer.

Northwestern Medicine Dermatologist Ahmad Z. Amin, MD, dives into common summer skin conditions beyond sunburn.

Heat Rash

“Heat rash develops when sweat gets trapped underneath your skin due to blocked pores,” says Dr. Amin. “It presents as reddish bumps on the skin that can feel itchy or even prickly.”

Infants, the elderly and people who are obese are at a greater risk for developing heat rash.

You can prevent heat rash by:

• Wearing breathable clothing in intense heat.
• Seeking a cooler environment and reducing time in extreme heat.

Treatment includes over-the-counter creams and sprays.

Bug Bites

You may only seek to avoid bug bites because they’re annoying, but protecting yourself against insects is vital in summer months to protect your health. Those bothersome bugs can carry insect-borne illnesses, like Zika virus, West Nile virus and Lyme disease.

Learn how to protect yourself and treat bug bites in this infographic.

Poison Ivy, Oak and Sumac

“The itchy, blistering rash associated with poison ivy, oak and sumac is caused by an oil in the leaves called urushiol. Many individuals are allergic to this substance,” says Dr. Amin. “The rash occurs when your skin encounters this oil, which is why you should wash your skin and any clothing immediately if you contact any of these plants.”

You can prevent poison ivy, oak and sumac rashes by:

• Wearing long sleeves, pants and gloves if you’re going to be in an area with any of these plants.
• Knowing what these plants look like and avoiding them.

If a rash appears, keep it clean, dry and cool. To treat itching, you can use calamine lotion or an over-the-counter cream containing diphenhydramine or hydrocortisone. Bathing in cool water with baking soda or oatmeal can also alleviate the itch. “The rash may need to be treated with topical steroids prescribed by a dermatologist. In severe cases, a patient may need several days of oral steroids.”

Athlete’s Foot

Fungi love warm, moist environments — just like your shoes in summer.

“The same type of fungi — dermatophytes — cause jock itch, ringworm and athlete’s foot,” says Dr. Amin. “They feed on the keratin in the hair, skin and nails, causing an itchy and often red scaly rash.”

Athletes foot can be treated with over-the-counter and prescription antifungal creams.

Swimmer’s Itch

“Known as cercarial dermatitis, swimmer’s itch is a reaction to a parasite that can be found in bodies of fresh water such as lakes and ponds,” says Dr. Amin.

Swimmer’s itch appears as bumps that look like pimples and can onset within minutes or even days after swimming in water with parasites. The rash usually affects exposed skin (not areas covered by the bathing suit). The condition will generally resolve on its own in a few days without treatment.

If treatment is needed, you can try:

• Over-the-counter anti-itch creams
• Bathing in baking soda or oatmeal to curb the itch
• Cool compresses to the affected area

Folliculitis

Just like fungi, bacteria thrive in warmth and moisture, and can cause folliculitis in warmer months. Folliculitis presents as red bumps or even pustules in areas on the body more prone to moisture, like the thighs and glutes in summer months.

“One of the most common causes of folliculitis is heat and sweat,” says Dr. Amin. “Wear looser clothing at the gym, shower after a sweaty workout, wash your workout clothes regularly and avoid lounging in sweaty clothes.”

Summer derm concerns? Consult a Northwestern Medicine dermatologist.