A severe sunburn is seriously unpleasant.

By Sarah Klein
Updated July 19, 2018

Spending too much time out in the sun can lead to a host of summer health hazards, from mild dehydration, to heat exhaustion, or worse, heatstroke. Of course, there’s also the constant threat of sunburn—in spite of your best efforts to diligently cover up with hats, sunglasses, and SPF. 

There’s no such thing as a “good” sunburn—but there’s definitely a bad one. Severe sunburn can result in an ultra-painful, red, blistery experience and even flu-like symptoms. All of these symptoms have earned severe sunburns a colloquial nickname: sun poisoning. 

Sun poisoning isn’t exactly a medical diagnosis, explains Mary L. Stevenson, MD, of the Ronald O. Perelman Department of Dermatology at NYU Langone Health. It also doesn’t have anything to do with actual poison. Rather, it's a lay term for a really, really bad sunburn.

Whether you call it a severe sunburn or a case of sun poisoning, here’s what you need to know about protecting—and treating—your skin.

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Sun poisoning symptoms

Sun poisoning shares a few symptoms with a regular sunburn, namely redness, blistering, and pain where the skin was exposed to the sun’s UV rays.  

But severe sunburns can also lead to swelling of the affected area or flu-like symptoms, such as headaches, fever, or nausea. Usually, you’ll start to notice sunburn symptoms within a few hours of being out in the sun, but sun poisoning may not rear its head for up to a day or longer, according to the Mayo Clinic.

What does sun poisoning look like?

You’ll recognize sun poisoning as a particularly painful-looking sunburn. In addition to that hallmark shade of lobster red, you might develop blisters or a rash. If you have underlying immune disorders or skin conditions, you may also experience photodermatoses, Dr. Stevenson says, or "skin eruptions or rashes that are abnormal skin responses to sun exposure." 

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Sun poisoning treatment

The very first thing to do when you notice a sunburn—severe or otherwise—is get out of the sun, recommends the American Academy of Dermatology.

Then, assess the damage. “Extreme blistering or symptoms of dehydration require a visit with a doctor who can examine, assess, and treat the symptoms and, in severe cases, treat the dehydration,” Dr. Stevenson says. If the blisters cover a large portion of your body, it’s a good idea to see a doctor right away.

A more mild sunburn is probably something you can handle at home. Start with cool showers or compresses to help relieve some pain and lower the temperature of your burned skin. Become very good friends with aloe vera gel, which “can provide a cooling effect that can ease symptoms,” Dr. Stevenson says. “Cold milk compresses can also provide relief as the lipids in milk can be soothing to the skin,” she adds.

An over-the-counter pain reliever like ibuprofen might also help tide you over until sunburn symptoms subside—usually within a few days. (Don't be surprised if your sunburn then starts to peel.)

Drink plenty of water too, since sunburns and sun poisoning can be dehydrating. “After being in the sun for too long, hydration is key, so make sure to drink up,” Dr. Stevenson says.

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Sun poisoning prevention

Since sun poisoning at its core is really a miserable sunburn, you just need to follow standard sun protection tips to avoid it.

Cover exposed skin with broad-spectrum sunscreen with an SPF of 30 or above to protect you from UVA and UVB rays. Make sure you’re using about a shot glass-size amount of sunscreen for your body and a teaspoon-size amount for your face and neck, and reapply every two hours, Dr. Stevenson told Health in a previous interview. Don’t forget to put it on sneaky places like your scalp and ears that are easy to miss.

Consider snagging some cute sun-protective clothing with UPF (like SPF for fabric) built in and limiting your sun exposure when those UV rays are strongest, typically between the hours of 10 a.m. and 4 p.m.