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Johns Hopkins Symptoms and Remedies

Johns Hopkins Medicine

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Psoriasis

What is it?

Psoriasis is a common, persistent skin disorder, characterized by patches of raised, red bumps covered with white, flaking scales. It generally develops on the scalp, knees, or elbows, although it may affect any area of the skin. The production of skin cells at affected sites is accelerated, either chronically or intermittently. Normally, new skin cells are constantly produced in the deepest layer of skin. From there, they rise to the top layer—the epidermis— where dead surface cells are shed, a process that typically takes about 28 days. However, in areas affected by psoriasis, new cells only take three to four days to reach the skin's surface, and the accumulation of excess cells causes the characteristic scaly plaques. Lesions may continue to enlarge slowly, or flareups of psoriasis may be separated by periods of remission. First attacks usually begin between the ages of 10 and 30. In rare cases psoriasis may cover the entire surface of the skin—see a dermatologist for immediate treatment. Although most cases of psoriasis can easily be controlled with treatment and do not represent a serious health risk, the disorder cannot be cured and may be itchy or occasionally painful and unpleasant to live with.

What Causes It?

  • The cause of psoriasis is unknown.
  • Hereditary factors may play a role.
  • Flare-ups may be triggered by infection, alcohol, stress, cold temperatures, or skin injury. Certain medications (such as antimalarial drugs and lithium) or initiation and withdrawal of intravenous or oral corticosteroids may produce a severe flare-up of total body (erythrodermic) or pustular psoriasis, which are medical emergencies.

Prevention

  • There is no known way to prevent psoriasis.
  • Avoiding or limiting exposure to common triggers may prevent flare-ups of psoriasis.

Diagnosis

  • Diagnosis is generally made by viewing the skin.
  • A skin biopsy may be needed to confirm diagnosis.

How to Treat It

  • Moisturizing skin creams can prevent dryness, particularly when applied immediately after bathing to retain the moisture absorbed by the skin.
  • Prescription creams or ointments containing cortisone (such as triamcinolone, fluocinolone, and fluocinonide), vitamin D, and/or vitamin A derivatives may be used to clear or control the psoriasis lesions.
  • Preparations and shampoos containing coal tar may soothe irritated skin.
  • Physician-supervised phototherapy or photochemotherapy (PUVA, using the drug psoralen and UVA radiation) may be needed.
  • In severe cases immunosuppressive or antiproliferative drugs such as methotrexate, acitretin, cyclosporine, or other medications may be used to clear or control the psoriasis.
  • New biological modifiers may soon be available by prescription.
  • Check with your doctor regarding any prescriptions you may take for other conditions since some medications may worsen symptoms.
  • Contact the National Psoriasis Foundation for information about support groups in your area.

When to Call a Doctor

  • Make an appointment with a doctor if symptoms do not respond to self-treatment.
  • Call a doctor immediately if you suddenly develop widespread psoriasis, with or without fever, joint pain, and fatigue.