Psoriasis is a chronic skin disorder that often comes and goes. Skin cells reproduce too rapidly and accumulate and form silvery patches on the surface of the skin. It can be mild to severe. Psoriasis is common, affecting more than 7 million people in the United States, but it occurs less in African, Asian, and Native American people. It affects men and women equally. It is a lifelong disorder that usually starts in adolescence or early adulthood.
Outbreaks can start with minor injury, stress, infections, exposure to cold and dry climates, obesity, and other autoimmune conditions. They can also occur without an obvious reason.
The cause is unknown but psoriasis is likely a genetic-based (inherited) autoimmune disease that affects the body’s immune system. Autoimmune means that the body’s immune system attacks normal parts of the body and causes injury or disease. Psoriasis is not infectious or cancerous.
Skin lesions are slightly raised, silvery white scales with red or pink margins. Raised areas of skin are called plaques. Painful cracks can appear. Lesions may be single, in certain body parts, or all over the body.
Skin of the scalp, face, elbows, hands, knees, feet, chest, lower back, and folds between buttocks is usually affected. Fingernails and toenails are often involved.
Itching may be present, and joint pain sometimes occurs. Scratching can cause bacterial infections. The skin’s appearance can lead to feeling embarrassed.
Up to a quarter of people with psoriasis have symptoms of arthritis (pain, swelling, stiffness in their joints [psoriatic arthritis]) that worsen when the psoriasis becomes more severe.
The health care provider makes a diagnosis from the look of the skin, nails, and scalp. The health care provider may do a skin biopsy (i.e., remove a small piece of skin) for study when the diagnosis is unclear. Dermatologists are doctors with special training in treating diseases of the skin.
Psoriasis is treatable but not curable. The goal of treatment is to decrease inflammation and control skin shedding. A health care provider who treats skin problems (dermatologist) may be involved in care. Avoiding things that trigger psoriasis and using prescribed medications can control and lessen symptoms. General measures include good skin hygiene, avoiding skin injury and dryness, exposing skin to moderate sunlight, and oatmeal baths. Treatment of mild to moderate psoriasis includes topical creams, lotions, shampoos, and ointments containing coal tar. These will reduce inflammation (redness), scaling, and itching. Steroids and other anti-inflammatory drugs applied to skin (topical) are for mild to moderate cases and as combination therapy for more severe cases. Other treatments include salicylic acid in mineral oil (removes plaques), PUVA (psoralen and exposure to ultraviolet light A [UVA]), immunosuppressant drugs (e.g., methotrexate, isotretinoin), antihistamines (for itching), and antibiotics (for secondary bacterial infections).
Contact the following sources: