by Jill Shuman, MS, RD, ELS
Psoriasis is a chronic, inflammatory skin disease. It speeds up the life cycle of skin cells and cause scales and red patches. Psoriasis can come and go over time. There are several types of psoriasis:
The cause of psoriasis is unclear. Signals from the immune system may cause the change in skin cells. The cells grow faster than they can be shed and pile up on the skin's surface. This pile up causes the patches.
Psoriasis may be more likely in those with one or more of the following:
The red, thickened, and rough patches of psoriasis may occur anywhere, but are commonly found on the scalp, elbows, knees, palms, and soles. Other symptoms include:
The skin may also be sore, burning, or itchy depending on the type of psoriasis.
The rashes and lesions may come and go.
You will be asked about your symptoms and past health. A physical exam will be done. It will include an exam of skin and nails. The doctor may make a diagnosis based on the appearance of the skin. There are no specific blood tests or diagnostic procedures for psoriasis. A skin biopsy may be done to confirm the diagnosis.
Treatment will be based on how severe it is and how much skin in involved. Choices may include:
Topical medicine is applied directly to the area. It may help to slow growth of patches or manage irritation. Other treatment may help eases itchiness or irritation. Choices include:
Photo (Light) Therapy
Psoriasis over large areas can be hard to treat with lotions or creams. Sunlight can help to clear or improve skin patches. The time in the sun should be managed to prevent sunburn.
Phototherapy can provide same benefits in a more controlled way. A form of phototherapy called PUVA uses a special light and a medicine that makes the body more sensitive to light. Phototherapy requires many treatments. It may cause side effects such as nausea, headache, and fatigue, burning, and itching. It can also increase the risk for skin cancer.
More severe psoriasis may need medicine that has a wider impact on the body. Choices include:
Avoiding physical trauma to the skin, infections, and cold, dry temperatures may help reduce flare-ups in people with the condition.
American Academy of Dermatology
National Psoriasis Foundation
Canadian Dermatology Association
Psoriasis Society of Canada
Moderate to severe psoriasis and psoriatic arthritis: biologic drugs. National Psoriasis Foundation website. Available at: https://www.psoriasis.org/about-psoriasis/treatments/biologics. Accessed January 26, 2021.
Psoriasis. American Academy of Dermatology website. Available at: https://www.aad.org/public/diseases/scaly-skin/psoriasis. Accessed January 26, 2021.
Psoriasis. DynaMed Plus website. Available at:
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Accessed January 26, 2021.
Systemic medications—methotrexate. National Psoriasis Foundation website. Available at: https://www.psoriasis.org/about-psoriasis/treatments/systemics/methotrexate. Accessed January 26, 2021.
Last reviewed November 2020 by EBSCO Medical Review BoardNicole S. Meregian, PA
Last Updated: 1/26/2021
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