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Psoriasis: Five Things You Need to Know

Private: Mital Patel, MD
Contributor Mital Patel, MD

An autoimmune disorder, psoriasis is a chronic skin condition that most often appears as red, scaly patches that itch, crack, and bleed. The most common areas of skin that are impacted by psoriasis include the scalp, elbows, knees, and lower back. An estimated 7.5 million Americans are living with this condition that, when treated, can be managed.

Here are five things you need to know:

1. The cause of psoriasis is still largely unknown.

While the exact cause of psoriasis is not known, researchers are actively studying treatments that help skin not react to the immune system. They also are looking at the association between the disorder and other conditions, such as high blood pressure, diabetes, and obesity. Generally, though, psoriasis is thought to be caused by abnormally fast-growing and shedding skin cells. The skin cells multiply quickly, causing the skin to shed every three to four days. It is also thought that the condition can be caused by a trigger – such as injury, sunburn, certain medicines, infection, stress, alcohol, or tobacco.

2. Psoriasis is not contagious, but it does run in families.

Anyone can get psoriasis and it affects both women and men and all ethnicities at the same rate. One risk factor for the disorder is if someone in
your family – father, mother, grandparent, aunt, uncle – has psoriasis.

3. Psoriasis also can be associated with arthritis, another autoimmune disorder.

In fact, up to 30 percent of people with psoriasis develop psoriatic arthritis, an inflammatory joint and tendon disease. That’s why treatment can involve specialists in both dermatology and rheumatology.

4. There are actually several different types of psoriasis.

Most cases of psoriasis, roughly four out of five, will be the type of psoriasis as described above. Other types include:

  • Nail psoriasis, which can cause malformed nails;
  • Guttate psoriasis, which looks like small pink drops on the skin with a finer scale on top;
  • Inverse psoriasis – particularly more common in the hot weather – appears as smooth and shiny red areas in the folds or creases of the skin under the breasts and on the armpits and groin;
  • Pustular psoriasis is a more rare type of the disease that causes blisters full of pus on hand palms, soles of the feet, or the toes and fingers;
  • Another more rare type, erythrodermic psoriasis appears on nearly all of the body’s skin.

5. Sunlight and ultraviolet artificial light are effective for treating psoriasis.

The sun’s natural ultraviolet light and sources of artificial ultraviolet light can help to decrease flare-ups of the condition. Other treatments include topical ointments, oral or injectable medications, or a combination of these therapies. Additionally, doctors often recommend that the skin be kept clean and moist and to avoid any specific triggers, such as stress.

Private: Mital Patel, MD
Mital Patel, MD

Mital Patel, MD, is a dermatologist and Director of the Hidradenitis Suppurativa and Neutrophilic Dermatosis Clinic at Brigham and Women's Hospital and an Instructor in Dermatology at Harvard Medical School.

Before you go,

Find out how to keep your skin healthy and learn when changes in your skin may be a sign of a health condition that should be checked out by a dermatologist. Read more articles about skin health.