As appealing as the long afternoons, soaring temperatures and time outside can be, they also signal a harsh environment that can assault the skin. This elastic, tough covering keeps our internal organs moist while keeping out microbes, insects and UV radiation. It protects us from abrasions and chemicals. It also plays a major role in thermoregulation, keeping our bodies cool through sweating.
"Luckily, skin has great regenerative capacity," says Ray Jalian, a cosmetic dermatologist at UCLA Medical Center. "The skin's epidermis has five layers, and the cells in the underlayers are constantly dividing." Skin cells take about a month to migrate to the outermost layer, where they are sloughed off and shed.
Still, skin is susceptible to external assaults. Skin provides lush habitat for an ecosystem of microorganisms, which can take hold and mount an infection. The same insects, chemicals and ultraviolet rays that skin protects us from can wreak havoc on the skin's defenses.
"There are several skin conditions that tend to get worse in the summer," says Dr. Sarah Gee, assistant clinical professor of dermatology at UCLA. Heat and sweat create the perfect environment for microbial colonies. And when people spend more time outdoors, they're more likely to encounter blood-seeking insects, poison oak and other irritants. Each summer, the dermatology clinic sees an influx of patients with rashes, bumps and skin irritations. What follows is a guide to some of the most common summer skin conditions.
Despite widespread warnings about the dangers of sun exposure, acute sunburn is still something that dermatologists see frequently in the summer, says Gee. Most people don't apply enough sunscreen, and they don't reapply it frequently enough. Sun exposure damages skin cells' DNA. If you were to look at sunburned skin under a microscope, you would see shriveled, dead cells. People with sunburn may experience dehydration, exhaustion and chills.
Prevention: Use a broad-spectrum sunscreen of SPF 30 or higher, and apply it generously. Each application on an average body should equal 1 ounce, or enough to fill a shot glass. Reapply every two or three hours, or after swimming or sweating heavily. Wide-brimmed hats and UV-protective clothing are good prevention, as is avoiding sun exposure from 10 a.m. to 2 p.m.
At-home treatment: There's nothing you can do to mitigate damage. But ice compresses, aloe vera or refrigerated moisturizer can provide relief for the pain. Ibuprofen can relieve pain and inflammation.
Complications: Possible infection from blistering; long-term increased risk of skin cancers, wrinkling and premature aging of the skin.
When to see a doctor: If you have a blistering sunburn, a sunburn that covers a large portion of the body or a sunburn accompanied by chills and fever.
The most common benign skin condition that tends to rear its head in summer is tinea versicolor, which means "many colors." A yeast that normally lives on human skin, tinea versicolor can grow out of control in hot, sweaty environments. Symptoms include white, brown, salmon or red patches, usually on the chest or back. The condition is not contagious.
Prevention: Wear loose-fitting clothing that keeps skin cool and dry; wash the body with dandruff shampoo a couple of times a week.
At-home treatment: Wash with dandruff shampoo and apply an over-the-counter antifungal cream.
Complications: None, though skin may remain discolored months after the infection has cleared. In some people, tinea versicolor reoccurs each summer.
When to see a doctor: If the condition worsens, doesn't go away or covers a large portion of the body.
Another common condition associated with heat and sweat is folliculitis: a superficial infection of the hair follicles that is usually caused by Staphylococcus aureus or other bacteria. Symptoms include a sprinkling of bright red pimples that may be itchy or sore. Though folliculitis is often seen in athletes, anyone can get it, particularly if hair follicles become damaged from razor burn, dermatitis, excessive perspiration or chafing.
Prevention: Wear loose-fitting, breathable clothing and shower soon after a workout; cleanse with acne wash to kill bacteria.
At-home treatment: Minor cases usually clear up within a few days. Avoid shaving the area while healing, and cleanse with an acne wash, applying an antibiotic ointment afterward. Warm compresses may help relieve discomfort and drain follicles.
Complications: Can develop into an abscess or cellulitis.
When to see a doctor: If infection doesn't clear up after several days or becomes painful, inflamed or starts to spread.
The West Coast cousin of poison ivy, poison oak contains a resin called urushiol that causes a red, blistering, itchy rash. Symptoms usually appear two or three days after contact, and the rash is often streaky or linear. Urushiol absorbs into skin rapidly, so the rash doesn't normally spread from person to person, but contaminated clothing, tools and even pets' fur can spread the rash.
Prevention: Learn to identify this plant, which has compound leaves arranged in leaflets of three — and avoid it. If contact occurs, wash immediately and thoroughly with soap and water or with a product designed to remove urushiol, such as Technu. Thoroughly wash all clothes, tools and pets that may be contaminated.
At-home treatment: Though the rash will clear on its own after a couple of weeks, hydrocortisone cream or calamine lotion can relieve itching. Lukewarm baths in a colloidal oatmeal preparation also can help. Try to avoid scratching, which can cause infection.
Complications: Bacterial infection; allergic reactions can spread the rash throughout the body.
When to see a doctor: If the rash spreads, becomes painful or blisters excessively; if itching is unbearable or doesn't respond to hydrocortisone cream.
In summer, mosquito bites are frequent, and some people are extremely allergic to mosquito saliva. Still, the most common bite Gee sees year-round is from bed bugs. "People come in with clusters of bites, and they say they wake up with them," she says. "A lot of times people think they are mosquito bites or spider bites, but when bites are reoccurring, think bedbugs." She adds that spider bites are actually uncommon. An acutely painful "spider bite" could be the sign of a staph infection.
Prevention: For bed bugs, the key is not to bring them home from traveling. For mosquitoes, keep skin covered with long sleeves and tuck pant legs into socks. Consider using bug repellent on exposed skin or hang mosquito netting in outdoor areas. Get rid of any standing water, including bird baths and kiddie pools.
Treatment: Itchy bites can be soothed with hydrocortisone cream or calamine lotion. Ice packs can reduce swelling and inflammation, and over-the-counter antihistamines can alleviate the reaction.
Complications: Bites can become infected with bacteria, especially from excessive scratching. Mosquitoes can transmit West Nile virus and other infectious diseases.
When to see a doctor: If a bite is painful and inflamed, doesn't go away on its own after a couple of days or if the skin reaction is worsening. A person should see a doctor any time a bite is followed by more severe symptoms, such as fever, body aches, headaches or swollen glands.Copyright © 2015, Los Angeles Times