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Take charge by learning as much as you can about psoriasis. The more you understand your condition, the easier it will be to manage.

What Causes Psoriasis?

Psoriasis seems to run in families. It’s a problem with the immune system.

When it works right, your immune system fights infections and heals injuries with white blood cells. If you have psoriasis, though, one type of white blood cell, the B-cell, creates antibodies that destroy normal skin cells.

Meanwhile, another type of white blood cell, the T-cell, starts to make too much of a protein called a cytokine. This seems to turn off a signal that controls the growth of skin cells.

Normally, skin cells last for about a month. Then they die, flake off, and are replaced by new ones.

If you have psoriasis, your immune system causes this cell turnover to happen in days instead of weeks. Layers of skin build up. Blood flow increases to try to nourish this skin, which leads to redness and swelling. You get reddened, inflamed skin with a whitish, flaky crust of dead cells on top.

How It Affects You

You may get patches of itchy, scaly, or inflamed skin called plaques. Though they can appear anywhere, you're most likely to get them on your knees, elbows, hands, feet, scalp, back, or belly button.

You may also get pits in your fingernails and toenails. About half of people with active psoriasis do. Up to 30% also get psoriatic arthritis, which causes pain, swelling, and stiffness in and around your joints.

Everyone is different. Your symptoms may be milder or more severe than someone else’s.

Try not to let psoriasis affect your social life or confidence. You can do all the things that anyone else does. If you feel like you're getting depressed, talk to your doctor or a counselor.

Different Kinds Have Different Symptoms

Plaque psoriasis. About 80% of people with psoriasis have this. It causes the raised red patches with white scales.

Guttate psoriasis. Children, teenagers, and young adults are most likely to get this. It often appears after an infection, such as strep throat. It causes red, scaly, raindrop-shaped spots, usually on the belly, arms, legs, and scalp. It often clears up on its own without treatment.