What's That Rash?

Psoriasis

Looks like: Thick, red patches of skin covered by flaky, white scales (this describes the most common kind, plaque psoriasis). Other types are guttate (small, red spots), pustular (white pustules surrounded by red skin), inverse (lesions in skin folds), and erythrodermic (widespread redness, itching, and pain).
Caused by: An immune system dysfunction that causes overproduction of skin cells. Though a chronic condition, psoriasis can be triggered by dry skin; minor skin injuries; stress; sunburn or UV deprivation; and some infections, like strep throat.
Feels: Sometimes painful and can be very embarrassing.
Where: Elbows, knees, or torso, but can appear anywhere.
Contagious: No.
Treatment: Keep skin lubricated. Depending on severity and location, treatment may include OTC cortisone creams, coal tar ointments, salicylic acid products, or dandruff shampoos. Exposure to sunlight can help clear skin (but avoid burning).
See a doctor if: Your skin doesn't clear with OTC treatment. Doctors can prescribe prescription INVALID ARTICLE ID, phototherapy (light therapy), systemic medications, or newer drugs called biologics, which target the body’s immune response.

Next: Eczema

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