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Psoriasis

What is psoriasis?

Psoriasis is a chronic skin condition. It causes inflamed, red, raised areas of skin that often develop dry, silvery scales called plaques. The plaques itch and can be painful. The condition most often occurs on the scalp, elbows, knees, and lower back.

Psoriasis is not contagious. It is an autoimmune skin disease. This means that the immune system has an abnormal reaction. It treats healthy skin like it is a foreign substance. This causes skin cells to grow faster than normal and to stack up in raised red patches. Psoriasis is a long-term (chronic) disease. You will have flare-ups that come and go over time.

There is no cure, but treatments can help ease symptoms.

What causes psoriasis?

Researchers don’t yet know what causes psoriasis. It may be caused by a mix of immune, genetic, and environmental factors. It is not contagious. It can’t spread to someone else who touches it. But it can be inherited.

The skin is the body's largest organ.  It protects you against injury and infection.  The outermost layer of your skin is the epidermis. The epidermis sheds old dead skin cells and replaces them with new ones. Normally, there is a balance between new skin and old skin.  With psoriasis, this process is unbalanced. 

Researchers think that certain cells of the immune system attack the skin as if it is unhealthy or needs repair. This causes skin cells to grow abnormally fast. Skin cells begin to stack up in raised red patches. The buildup of dead skin cells forms thick, silvery scales (plaques).  

This may be caused by a trigger, such as injury, sunburn, some kinds of medicines, infection, stress, alcohol, or tobacco.

Who is at risk for psoriasis?

You are more at risk for the condition if you have a brother, sister, or parent with psoriasis. Psoriasis can start at any age. It is most common between ages 30 and 39 and ages 50 and 69.

Other things that put you at risk include:

  • Smoking

  • Obesity

  • HIV or strep infections

  • Certain medicines such as those for high blood pressure (beta blockers), bipolar disorder (lithium), and medicines for malaria

  • Heavy alcohol use

  • Stress

What are the symptoms of psoriasis?

Psoriasis comes in several forms. Symptoms can occur a bit differently in each person. They can include:

  • Plaque psoriasis. This type of psoriasis is the most common. Symptoms may include patches of red, raised skin on the torso, arms, legs, knees, elbows, genitals, and scalp. Nails may also thicken, become pitted, and separate from the nail beds. Plaques on the joints can limit movement.

  • Pustular psoriasis. Symptoms include small blisters (pustules) filled with pus. They don’t have bacteria in them. The pustules may be all over the body or just on the palms, soles, and other small areas.

  • Guttate psoriasis. This type of psoriasis affects mostly children. Symptoms may include many small spots of red, raised skin. A sore throat (strep) usually comes just before of this type of psoriasis.

The symptoms of psoriasis can be like other health conditions. Make sure to see your healthcare provider for a diagnosis.

How is psoriasis diagnosed?

Your healthcare provider will ask about your symptoms and health history. He or she may also ask about your family’s health history. He or she will give you a physical exam. The physical exam may include a close exam of your skin and nails. You may also have tests, such as a skin biopsy. A small piece of your skin is removed and sent to a lab.  A biopsy may be done because psoriasis can look like fungus or pityriasis rosea on the skin. 

How is psoriasis treated?

Treatment will depend on your symptoms, your age, and your general health. It will also depend on how severe the condition is and where on your body the plaques are located.

There's no cure for psoriasis, but the symptoms can be managed. The goal of treatment is to reduce inflammation and slow down the rapid growth and shedding of skin cells. You may have a combination of treatments. Treatment may include:

  • Ointment and cream to moisturize your skin

  • Ultraviolet light therapy (phototherapy) in a medical office

  • Timed phototherapy in outdoor sunlight

  • Laser treatment

  • Steroid cream

  • Vitamin D cream

  • Cream with salicylic acid

  • Coal tar ointment or shampoo

  • Anthralin, an anti-inflammatory medicine that treats the thicker patches of psoriasis

  • Retinoid medicine in cream, ointment, or pills

  • Medicines that suppress the immune system, such as cyclosporine or methotrexate

  • Biologic medicine that is injected

Talk with your healthcare providers about the risks, benefits, and possible side effects of all treatments.

What are possible complications of psoriasis? 

In some cases, psoriasis also causes arthritis. This is known as psoriatic arthritis. It causes pain, swelling, and stiffness in the joints. Psoriasis can raise your risk for diabetes, heart disease, and lymphoma. People with psoriasis are also more likely to have emotional stress and depression. Severe psoriasis can lead to erythroderma. In that condition, the skin all over the body is red and inflamed. 

What can I do to prevent psoriasis?

Researchers don’t know how to prevent psoriasis. But newer medicines can control psoriasis very well.

How to manage psoriasis

Psoriasis is a chronic condition. But you can manage it by working with your healthcare provider to create a long-term treatment plan and self-care routine.

Symptoms may come and go. Some factors can affect how often symptoms occur, how severe they are, and how long they last. These factors include:

  • Stress

  • Infection

  • Certain medicines

  • Smoking

  • Sun exposure

  • Drinking alcohol

Follow these steps to help manage your symptoms:

  • Keep your skin clean and moist. Take baths to help soften scales. Use warm water, not hot water. To prevent drying out your skin, limit each bath to about 15 minutes. Use mild soaps that have added oils, fats, or moisturizers. Try soaking in a tub with added bath oils, oatmeal, apple cider vinegar, or Epsom salts. Use a scalp treatment as prescribed.

  • Stay away from irritants. Don’t use deodorants, antiperspirants, or antibacterial soaps. Don’t use abrasive cleansers, harsh detergents, or household chemicals.

  • Get more omega-3 fatty acids in your diet. This can help improve dry skin. The best sources are fatty fish such as salmon, mackerel, lake trout, and albacore tuna. You can also add fish oil to a juice, shake, or smoothie. Try flaxseeds and flaxseed oil, canola oil, walnuts, soybean, and tofu. These have fats that are converted to omega-3 fatty acid in the body.

  • Stay at a healthy weight. Skin folds can be a site for psoriasis plaques. If you are overweight, talk with your healthcare provider about a weight-loss program.

  • Stay away from things that trigger flare-ups. Stop smoking. Ask your healthcare provider for help. Seek treatment right away for any illnesses or skin injuries. These can cause flare-ups. Manage your stress, and use relaxation methods.

  • Eat a healthy diet. Psoriasis can increase your risk for diabetes and heart disease. Eat plenty of fresh fruits and vegetables, whole grains, and lean meats.

  • Stick with treatment. Keep on the treatment plan that your healthcare provider has advised for you.

When should I call my healthcare provider?

Call the healthcare provider if you have:

  • Skin pain that gets worse

  • Bleeding from the skin plaques that is hard to control

  • Signs of skin infection such as fever, redness, worse pain, swelling, pus

  • Aching or stiffness in your joints

  • Changes in your fingernails

  • Changes in mood, such as depression

  • Joint pain or changes in how the joint looks

Key points about psoriasis

  • Psoriasis is a chronic skin condition. It causes inflamed, red, raised areas of skin that often develop dry, silvery scales called plaques.

  • Psoriasis is not contagious. It is an autoimmune skin disease.

  • Psoriasis is a long-term (chronic) disease. You will have flare-ups that come and go over time.

  • There is no cure, but treatments can help relieve symptoms. Treatment can include creams, light therapy (phototherapy), and oral or injected medicine.

  • Psoriasis is a chronic condition. But you can manage it by working with your healthcare provider to create a long-term treatment plan and self-care routine.

Next steps

Tips to help you get the most from a visit to your healthcare provider:

  • Know the reason for your visit and what you want to happen.

  • Before your visit, write down questions you want answered.

  • Bring someone with you to help you ask questions and remember what your provider tells you.

  • At the visit, write down the name of a new diagnosis, and any new medicines, treatments, or tests. Also write down any new instructions your provider gives you.

  • Know why a new medicine or treatment is prescribed, and how it will help you. Also know what the side effects are.

  • Ask if your condition can be treated in other ways.

  • Know why a test or procedure is recommended and what the results could mean.

  • Know what to expect if you do not take the medicine or have the test or procedure.

  • If you have a follow-up appointment, write down the date, time, and purpose for that visit.

  • Know how you can contact your provider if you have questions.

Online Medical Reviewer: Kevin Berman, MD
Online Medical Reviewer: Louise Cunningham, RN
Online Medical Reviewer: Michael Lehrer, MD
Date Last Reviewed: 11/1/2018
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