If you develop a rash after exposure to sunlight, you might be experiencing solar urticaria. The rash can vary from person to person and might include
- Small, raised bumps
- An itching or burning sensation
- Swelling or blistering on exposed areas
These symptoms often show up on skin that was newly exposed to the sunlight. Skin that is always exposed, such as the face and hands, might not break out. Also, even though some skin might have been covered by clothing, it can still show these symptoms, too [New Zealand Dermatological Society].
Solar urticaria usually appears within half an hour of exposure to sunlight and typically goes away quickly. If the skin is protected from the sun, the rash should disappear within a few hours and almost always within a day [source: Baron]. If the rash is exposed to more sunlight, it could be dangerous [source: Salford Royal]. In some people, solar urticaria reoccurs and becomes a chronic condition [source: Asthma and Allergy Foundation of America].
People with solar urticaria also might feel sick. Other symptoms can include headache, nausea or fainting [source: Baron]. You should consult your doctor if the rash persists or worsens, or if it covers a large area of your body that was protected by clothing. You should seek medical attention immediately if the rash is accompanied by swelling around your lips or eyes, or if you have trouble breathing or swallowing, or feel faint. These can be serious signs of an allergic reaction and might be symptoms of something other than solar urticaria [source: Harvard Medical School].
Now that you know what to look for, read on to learn how to treat it.