Sun Poisoning: Signs and Symptoms

Sun poisoning is the term used to refer to a severe case of sunburn. You can develop it when your unprotected skin is exposed to the sun’s ultraviolet (UV) rays for too long.

Compared to sunburn, sun poisoning causes broader and more serious symptoms. With sun poisoning, more than just the skin is affected. In addition to inflamed, painful, and red skin, sun poisoning causes allergy- or flu-like symptoms such as fever, chills, nausea, and rash.

The symptoms can develop gradually, taking about 4-24 hours after sun exposure. However, while sunburns typically resolve within three to five days, sun poisoning symptoms can last longer.

Sun poisoning isn’t a clinical diagnosis, and it isn’t a true type of poisoning. However, knowing the symptoms associated with severe sunburn can help you better understand what to expect if you develop what many refer to as sun poisoning.

Sun poisoning causes a series of changes to areas of skin exposed to the sun, which can last anywhere from several days to several weeks. Since sun poisoning is a severe form of sunburn, the skin symptoms overlap considerably.

Within several hours to one day after exposure to sunlight or other UV rays, you can experience the following skin changes when your skin is burned:

• Redness, severe pain, and warmth
• Skin that stings or is painful to the touch
• Blisters, or fluid-filled growths on the skin that can burst
• Peeling skin
• Rash, which can look like the red bumps associated with hives
• Itchiness

These symptoms tend to worsen for 24-36 hours and resolve within five days. A layer of the affected skin eventually peels off several days after exposure. Skin symptoms with sun poisoning are generally more severe and last longer than sunburn.

Having darker skin reduces your chance of developing sunburn but doesn’t eliminate it completely. This is because skin’s melanin—the substance that gives skin its color—protects skin from UV rays. Darker skin has more melanin, which means more protection from the sun.

Still, people of every skin tone must protect themselves from the sun. When people with darker skin get sunburn, their skin might not appear red but can get darker.

Photodermatosis

Certain skin-related sun poisoning symptoms may be the result of photodermatosis. This is a skin reaction associated with autoimmune conditions (when the immune system attacks healthy cells, tissues, or organs by mistake) or medication side effects. It causes a rash that resembles hives and causes itchy skin.

Autoimmune disorders such as lupus, psoriasis, and eczema can prompt photodermatosis. You may also develop the reaction if you take certain medications, including antibiotics, non-steroidal anti-inflammatory drugs (NSAIDs), diuretics (water pills), and antihypertensive drugs (used to treat hypertension, or high blood pressure).  

If the area affected by photodermatosis is protected from further UV exposure, the symptoms tend to resolve within a couple of days.

While sunburn symptoms primarily affect the skin, sun poisoning can cause a wider set of effects throughout the body. This is mainly because severe sunburn can lead to dehydration (not taking in enough water). You may also be likelier to develop heat exhaustion or heat stroke, conditions that can begin as your body temperature rises due to being in the hot sun.

As a result, people with sun poisoning may experience dehydration, heat exhaustion, or heat stroke symptoms. These symptoms can affect different systems and may be similar to flu symptoms or allergic reactions. They can include:  

• Headaches
• Fever or chills
• Fatigue
• Nausea and vomiting
• Confusion or difficulty concentrating  
• Elevated or rapid heart rate
• Fainting
• Decrease in urination
• Very dark-colored urine
• Intense thirst
• Dry mouth and tongue

In most cases, the symptoms of sun poisoning resolve on their own. However, sun poisoning can cause more serious effects even after the initial symptoms disappear. Repeated sunburn or sun poisoning damages the skin, leading to wrinkles, dry or leathery skin, and age spots (darker areas of skin).

More concerning, however, is that excessive sun exposure raises the risk of skin cancer. Repeated sun poisoning (and even milder sunburns) increases your chances of developing all three major forms of skin cancer. This is especially true of malignant melanoma, the most severe form of skin cancer that spreads and can be fatal.

Common initial signs of skin cancer include:

• New moles or changes to already-existing mole
• Dome-shaped skin growths
• Patches of scaly skin
• Sores of varying sizes that bleed, ooze, or do not heal

While most cases of sun poisoning clear up on their own, certain symptoms may be signs of complications that are considered medical emergencies.  Heat stroke and dehydration, in particular, may require medical attention.

Get immediate medical care if you experience any of the following symptoms:

• Faintness or dizziness
• Rapid, shallow breathing
• Elevated heart rate
• Sunken eyes
• Lack of urination
• Extreme thirst
• Pale, damp, clammy, or cool skin
• Nausea
• Light sensitivity or eye pain
• Severe blistering of skin
• Fever
• Extreme pain for 48 hours or more
• Severe sunburn on more than 15% of your body

Sun poisoning is a severe form of sunburn. In addition to inflammation, redness, and pain in the affected skin, sun poisoning can cause flu- or allergy-like symptoms. Depending on the case, you may experience blisters, an itchy rash, headache, fever, and chills.

While most cases of sun poisoning resolve on their own, the condition can lead to serious complications. Severe and persistent sunburn pain, loss of consciousness, elevated heart rate or breathing, and high fever are some of the signs you need immediate medical help.