Lupus patients are very sensitive to UV rays. Sometimes, even a little exposure to the sun (UV rays) can trigger a flare of itching, rashy skin, aching muscles, low grade fever, and/or extreme fatigue. In lupus, the body´s immune system goes awry and instead of protecting against foreign invaders, it mistakenly attacks its own skin, joints, kidneys, brain, heart, lungs and blood. Abnormal light sensitivity also known as "photosensitivity" is a major feature of the different forms of lupus including systemic lupus erythematosus (SLE) and cutaneous lupus (which is mainly limited to the skin). Photosensitivity is defined as a skin rash that develops as a result of an unusual reaction to sunlight. UV light causes skin cells to express particular proteins including one called "Ro." These proteins may then be the targets of antibodies, which are thought to attract white blood cells, which attack the skin cells, leading to the inflammation that causes the rash. When people with lupus are exposed to UV rays, they can, and often do, develop new skin lesions and may even develop flares of internal lupus including joint pain and fatigue.
There are several ways that the skin can show manifestations of sun sensitivity. The butterfly rash, a faint or prominent red rash over bridge of the nose, is common. People with subacute cutaneous lupus may develop a red pimple-like rash that comes out first. As this rash persists, these spots become bigger and scales may even appear. It can be itchy and usually shows up on the face, chest or arms and commonly comes on after sun exposure. The rash usually worsens with increased sun exposure.
Another type of skin manifestation starts out as a flat lesion and expands outward. These leasions appeas on the face, chest, arms and back and are very sensitive to the sun and tends to be very itchy. When it resolves, it leaves no permanent scarring.
Chronic discoid lupus lesions is a form of lupus classically thought to only affect the skin. Unlike its cousins, the slightly elevated, pink or red areas which form crust or flake on the surface, these are characteristically likely to scar.
In addition, some medications routinely taken by people with lupus increase the effects of the sun. People taking so-called "photosensitizing" medications may need extra protection against sunlight.
If you must be out in the sun, wear broad-brimmed hats and tightly woven, loose-fitting clothing with long sleeves and long pants. Rit Sun Guard Laundry Treatment UV Protectant can be washed into clothing to add extra UV protection, instantly turning ordinary cloth with an SPF of 4 into SPF 30 material.
Use a broad-spectrum sunscreen with an SPF rating of at least 30. The broadest protection against both UV-A and UV-B is in sunscreens that contain avobenzone (Parsol 1789 aka avobenzone) or physical blockers such as titanium dioxide and/or zinc oxide (see sunscreen post in Lauri's Lounge).
Also, as Sits-In-The-Corner suggested, it is important that you talk to your doctor about the rash and when it occurred so that you and he can determine exactly what type of rash it is and what type of treatment and/or protection is needed.
I wish you the best and keep us posted!
Peace and Blessings
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