Got a Sunburn? Here’s How To Tell if It’ll Turn Into Sun Poisoning (and What To Do About It)

Chances are, you know sunburn when you see it (or just as likely, feel it). Skin that’s soaked up too much of the sun’s ultraviolet (UV) rays without protection can become red, painful, and inflamed. And while sunburn is common—research suggests as many as a third of U.S. adults experience at least one a year — it’s still serious. Having five or more sunburns in your life more than doubles your melanoma risk, according to the Skin Cancer Foundation.

Even though all sunburns are serious, some are more severe and can become intensely painful (think: sun blisters). This is known as “sun poisoning,” and like sunburn, it’s caused by excessive exposure to sunlight. But with sun poisoning, symptoms worsen and affect far more than just your skin.

Read on for more about sun poisoning, including how it happens, symptoms to look out for (it’s not exactly the same as a sunburn), and expert-backed tips to prevent sun poisoning in the future.

Wait, how is sun poisoning different from sunburn?

Though it isn’t an *official* medical diagnosis, most experts recognize sun poisoning as an extreme case of sunburn. “Sun poisoning is a very severe sunburn caused by excessive sun exposure causing painful, red skin that blisters and sloughs off,” says Maya Thosani, MD, a double-board certified dermatologist and owner of Modern Dermatology in Scottsdale, Arizona.

If you have sun poisoning, your body hasn’t actually been poisoned by the sun — rather, you’re experiencing an inflammatory response to UV exposure, and you may also be dehydrated.

Initially, a case of sun poisoning looks a lot like a “regular” sunburn. But after a few hours, other symptoms can develop, according to the Cleveland Clinic. Here’s what that might look like:

• Sunburn: With your standard sunburn, skin looks red and swollen. It may feel itchy and warm to the touch, and after some time, the burn may develop small, fluid-filled blisters, the Mayo Clinic notes.
• Sun poisoning: Skin is very red and painful, and can blister or peel. You might experience fever and chills, dehydration, joint or muscle pain, nausea and vomiting, headaches, dizziness, or fainting. Some people with sun poisoning also develop blisters on their lips.

Although we know sun poisoning is caused by excessive UV radiation, experts are still learning exactly why it happens to some people and not others. “Sun poisoning is not extremely common, although can occur if [someone has] not adequately protected [their] skin, or in individuals who are particularly sensitive to sunlight,” says Tiffany Jow Libby, MD, a dermatologist and the director of Mohs Micrographic and Dermatologic Surgery at Brown Dermatology in East Providence, Rhode Island.

While everyone should take steps to protect their skin from the sun, people with less natural melanin may have a higher risk of sun poisoning, Dr. Thosani adds, such as those with very fair skin, red hair, and green eyes. For a person with these features, “it could take as little as 15 minutes of sun exposure to cause a burn,” she says.

Taking certain medications or having a health condition like lupus may also up your chances of developing sun poisoning.

The best ways to treat sun poisoning

Suspected sun poisoning warrants a call to your doctor, and your practitioner may recommend additional treatments depending on how severe your symptoms are. You may be able to manage a mild case of sun poisoning at home (just make sure to get your doc’s okay). All of the below can also be used to treat “regular” sunburn and may also be helpful for sun poisoning:

• Stay hydrated. Sun poisoning often goes hand in hand with dehydration, experts say, so drink plenty of water to help replace lost electrolytes. If you’re having trouble keeping liquids down, get in touch with your doctor right away — severe sun poisoning may require intravenous fluids, Dr. Thosani says.
• Apply a cool compress. The area where your skin has been burned likely feels hot to the touch and very painful. A cool compress can help soothe the burn and reduce inflammation, says Dr. Libby.
• Use a soothing moisturizer. Aloe vera gel or a gentle, fragrance-free moisturizer or balm can help heal burned, blistered skin. Keeping the area moisturized will also help prevent scarring. If your skin feels especially itchy and inflamed, a topical antihistamine may also help provide relief. Coconut oil can help heal a sunburn, too, but you should only apply it once your skin is no longer hot to the touch, or you’ll risk making the burn and your symptoms worse.
• Manage the pain. Sun poisoning can be incredibly painful. Besides cool compresses, calamine lotion or colloidal oatmeal bath can help with pain, per the American Academy of Dermatology Association. If those don’t work, then try over-the-counter pain relievers like ibuprofen or acetaminophen (Tylenol) to help reduce pain and inflammation.
• Avoid further sun exposure. It may seem obvious, but this one is critical: If you have sun poisoning, additional UV exposure will only exacerbate the damage. Stay out of the sun as much as possible to give your skin a chance to heal, and make sure to cover up the area (such as with long sleeves, a hat, and sunscreen) before you do go outside again.

How to prevent sun poisoning

The surest way to prevent sun poisoning is to minimize the amount of time you spend in the sun, particularly during the hottest and brightest part of the day. When you go outside, take these steps to keep skin protected:

• Sunscreen is a must… “Be diligent about wearing sunscreen that has at minimum SPF 30,” says Dr. Libby. “Remember to apply two-finger lengths worth to your entire face to achieve the SPF on the bottle.” The Skin Cancer Foundation recommends applying a broad-spectrum sunscreen (this will protect against both UVA and UVB rays) about 30 minutes before you go outside, then reapplying it every two hours or immediately after swimming.
• …but don’t rely on sunscreen alone. No sunscreen is 100% effective, Dr. Libby notes. For this reason, it’s just as important to use a multi-layered protection strategy by wearing clothing (ideally with UPF sun-protection fabrics), a hat with a broad brim, and sunglasses whenever you’re outside.
• Be extra careful near water. Dr. Thosani points out that beach days can be particularly dangerous, because water amplifies your sun poisoning risk. “Excess UV exposure can occur when in the water where the sun’s rays magnify and simultaneously reflect back,” she explains. “These severe burns lead to sun poisoning.”
• Stay in the shade during the middle of the day. UV rays are at their peak between 10 a.m. and 4 p.m., according to the U.S. Environmental Protection Agency (EPA), so try to limit your outdoor time during those hours. And don’t assume you’re in the clear on cloudy days: “It can be easier to get sun poisoning than one realizes due to the harshness of UV rays mid-day, even in cloudy weather,” says Dr. Thosani.

When to see a doctor

Reach out to your doctor if you have any symptoms of sun poisoning. While some sun poisoning cases are mild enough to be managed at home with the remedies above, more serious burns require stronger treatments. Depending on the severity, your doctor may recommend a combination of IV fluids, oral steroids, topical antibiotics, and possibly prescription pain medications for a more serious burn.

It’s especially important to let your doctor know ASAP if you notice your burn blistering (this could be a sign that it’s becoming infected), or if you’re experiencing extreme pain even after trying home treatments.

People with sun poisoning could also have heat stroke, which is the most serious heat-related illness, according to the Centers for Disease Control and Prevention (CDC). If you have symptoms such as hot and dry skin, seizures, confusion, or loss of consciousness, call 911 or go to the emergency room right away.

FAQ

What does the beginning of sun poisoning look like?

At first, sun poisoning resembles a regular case of sunburn. Within a few hours of sun exposure, your skin will likely appear red, inflamed, and swollen, and feel tender or even a little painful. But with sun poisoning, you’ll quickly start to notice more serious symptoms. “The systemic symptoms, such as dehydration, nausea, and flu-like symptoms, are what contribute to it becoming sun poisoning,” says Dr. Thosani.

In addition to all of the above, you may start to feel dizzy, lightheaded, or feverish, and develop a headache, chills, or blisters.

How long does sun poisoning last?

While a “regular” sunburn typically starts to improve after a day or two, sun poisoning can last longer. “It depends on the severity, but the most severe symptoms may last up to a week,” says Dr. Libby.

What should I drink if I have sun poisoning?

Drinking plenty of water or electrolyte-rich fluids can help your body restore balance, Dr. Thosani says. It can also help to make sure to get enough salt, she adds, because this can also help maintain hydration.

—reviewed by Jennifer Gilbert, MD, MPH