A severe case of sunburn can lead to sun poisoning. Symptoms may start out similar to a sunburn, but sun poisoning can lead to complications like infection or increased risk for skin cancer if left untreated.

Sun poisoning refers to a case of severe sunburn. It occurs after you’ve been exposed to ultraviolet (UV) rays from the sun for an extended period of time.

Also known as polymorphic light eruption, sun poisoning can come in different forms based on your sensitivity to the sun. Unlike a mild sunburn, sun poisoning usually requires medical treatment to prevent complications.

With sun poisoning, you may first experience symptoms of a regular sunburn. Sunburn symptoms can appear within 6 to 12 hours of exposure to UV rays. It’s important to distinguish between the symptoms of a sun rash, sunburn, and sun poisoning.

Sun rash

A sun rash (sun allergy) develops from sun exposure, sun poisoning, or exposure to outdoor plants such as parsnip. It’s sometimes hereditary. The resulting symptoms of a sun allergy reaction look like a widespread red rash. It’s also extremely itchy. The rash can develop small bumps that look like hives.

Sun allergies occur regularly from sun exposure and may need regular treatment from a dermatologist. A sun rash that develops from sun poisoning is more of an isolated event that needs medical attention.

Mild sunburn

In cases of mild sunburn, you might experience redness, pain, and swelling. A sunburn eventually heals on its own, although applying aloe vera gel can help soothe your skin.

Sometimes a cold bath or over-the-counter pain relievers can relieve discomfort, too. Eventually, sunburn heals on its own without any significant complications.

Symptoms of sun poisoning

Sun poisoning, on the other hand, is significantly worse than a mild sunburn. In addition to the usual sunburn-like symptoms, you might experience:

  • blistering or peeling skin
  • severe redness and pain
  • fever (and sometimes chills)
  • dehydration
  • confusion
  • nausea or vomiting
  • headaches
  • dizziness
  • fainting

The term “sun poisoning” can be a bit misleading, as it presumes you are somehow poisoned because of sun exposure. Sun poisoning actually refers to a severe burn from UV-ray exposure. This can happen from being out in the sun too long, not wearing sunscreen, or perhaps forgetting to take extra precautions if you’re at an increased risk for sunburn.

You may also be at an increased risk of sun poisoning if you:

  • have fair skin
  • have relatives who’ve had skin cancer
  • are taking antibiotics
  • take oral contraceptives
  • are using certain herbal supplements, such as St. John’s wort
  • apply citrus oils to the skin prior to sun exposure
  • live in a region that’s near the equator
  • reside in high altitudes (such as mountainous regions)
  • frequent the beach, as sunlight reflects more intensely off sand and water
  • engage in regular snow activities during the winter — sun reflects off snow, too
  • are using alpha hydroxy acids (AHAs), such as chemical peels

If you think you have sun poisoning, you need to see a doctor right away. They can help provide treatment to prevent related complications, such as skin damage and severe dehydration.

In some cases, you might need to go to the emergency room, especially if you are dehydrated or have flu-like symptoms, such as fever or muscle aches.

At the ER, your doctor will check your vitals, as well as the severity of your sunburn.

Your doctor may treat sun poisoning with cool water or compresses. Applying lotion to your skin while it’s damp can help peeling skin retain the most moisture possible. Also, drinking fluids can help replenish moisture lost from extremely dry skin.

Sun poisoning may also be treated with:

  • intravenous (IV) fluids for dehydration
  • steroid creams for painful blistering sunburns
  • oral steroids for pain and swelling
  • prescription pain medications if OTC versions aren’t providing relief
  • topical antibiotics to prevent infection

Sun poisoning, when treated promptly, will heal over time. In the most severe cases, people with sun poisoning may be transferred to the hospital’s burn unit.

When left untreated, sun poisoning can lead to potentially life-threatening complications. Dehydration develops quickly, so it’s important to drink water or electrolytes after you’ve been in the sun.

Infection is also a possibility. This can develop if your skin is punctured from scratching at the burn, or from popping blisters. To prevent infection, let your skin be. If you notice any oozing or red streaks, see your doctor right away. This could indicate a more severe infection that has possibly spread to your bloodstream, and you may need oral antibiotics.

Another complication of sun poisoning may not appear until long after the burning, blisters, and pain have gone away. People who experience severe sunburns are at a higher risk of developing premature wrinkles and skin spots later in life. Your risk for skin cancer may also increase.

Sun poisoning is a severe complication of sunburn, and it can get worse if you don’t treat it right away.

A typical mild sunburn heals within a week. Sun poisoning, on the other hand, can take several weeks to completely go away — it all depends on the extent of the damage to your skin.

The best way to prevent sun poisoning is to minimize unnecessary UV exposure. First, you should wear sunscreen every day, regardless of whether it’s a warm, sunny day, or a cold cloudy day. Vanderbilt University Medical Center recommends a sunscreen of at least 30 SPF. Make sure the product you’re using guards against both UVA and UVB rays for the most protection. You’ll need to reapply your sunscreen if you sweat or go swimming — preferably every two hours in these instances.

You can also reduce excessive exposure by wearing hats and cool cotton clothing. Also, consider staying indoors when sun rays are at their highest: 10:00 a.m. to 4:00 p.m.