sun exposure causes exaggerated sunburn-like reactions and skin rashes, yet sunlight can precipitate lupus flares involving other parts of the body. For this reason, sun protection is very important for people with lupus. Since both UV-A and UV-B rays are known to cause activation of lupus, patients should wear sunscreen containing Helioplex and an SPF of 70 or higher. Sunscreen should be applied everywhere, including areas of your skin covered by clothing, since most clothing items contain an SPF of only about 5. Be sure to reapply as directed on the bottle, since sweat and prolonged exposure can cause coverage to dissipate.