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Psoriasis

Condition Basics

What is psoriasis?

Psoriasis plaque on a knee.

Psoriasis is a chronic skin condition that causes skin cells to grow too quickly. The result is thick white or red patches of skin. The patches (called plaques) can range in size from small to large. They usually occur on the knees, elbows, scalp, hands, feet, or lower back.

What causes it?

Experts believe that the immune system overreacts, causing inflammation and flaking of skin. In some cases, psoriasis runs in families. People with psoriasis often notice times when their skin gets worse. Things that can cause these flare-ups include a cold and dry climate, infections, stress, dry skin, and certain medicines.

What are the symptoms?

There are several types of psoriasis. Symptoms for each may vary. But major symptoms are itchy and tender skin and raised, bright red patches of skin (called plaques), topped with loose, silvery scales. In some people, psoriasis causes joints to become swollen, tender, and painful. Symptoms may disappear, even without treatment, and then return.

How is it diagnosed?

Your doctor can often recognize psoriasis by looking at your skin, scalp, and nails. Special tests usually aren't needed.

How is psoriasis treated?

Most cases of psoriasis are mild. Treatment starts with skin care. This includes keeping your skin moist with creams and lotions. These are often used with other treatments including shampoos, ultraviolet light, and medicines your doctor prescribes. You may need to try different combinations of treatments to find what works for you.

Current as of: November 16, 2023

Author: Ignite Healthwise, LLC Staff

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