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Psoriatic Arthritis


The Manual's Editorial Staff

Last full review/revision Apr 2020| Content last modified Apr 2020
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Arthritis is a group of diseases that makes your joints hurt, swell up, and turn red. There are many different types of arthritis.

What is psoriatic arthritis?

Psoriatic arthritis is a type of arthritis that affects some people with psoriasis. Psoriasis is a skin condition causing flare-ups of red, scaly rashes and thickened, pitted nails.

  • Psoriatic arthritis can affect any joint, but it usually develops in the spine, hands, and feet

  • Doctors look at your symptoms to tell if you have psoriatic arthritis

  • Medicines can sometimes help

What causes psoriatic arthritis?

Psoriatic arthritis happens when your body's immune system (organs and cells that fight infection) attacks your joints and tissues around them. Doctors don’t know exactly why this happens.

You're more likely to get psoriatic arthritis if someone in your family has it.

What are the symptoms of psoriatic arthritis?

You may have one or more of the following:

  • Joints at the tips of your fingers and toes become inflamed (swollen, red, and warm)

  • Pain in the back of the ankle (Achilles tendinitis) or sole of the foot (plantar fasciitis)

  • Back pain

  • Pain in your hips and knees

  • Joints that are inflamed for a long time may become deformed

Psoriasis causes a rash. The rash may appear before or after you have joint pain. You may not notice the rash if it's hidden in your scalp, navel, or creases of your skin. The skin and joint symptoms sometimes appear and disappear together, but often either the skin or the joint symptoms are worse than the other.

How can doctors tell if I have psoriatic arthritis?

Doctors can tell if you have psoriatic arthritis based on your symptoms and family history and by doing an exam. They will also do tests:

  • X-rays to see how damaged your joints are

  • Blood tests to rule out other types of arthritis

  • Sometimes tests to look at joint fluid, if the joint is swollen

How do doctors treat psoriatic arthritis?

Doctors will prescribe medicines to control the rash and lessen the swelling in your joints. Medicines that can help psoriatic arthritis include:

  • Acetaminophen and nonsteroidal anti-inflammatory drugs (NSAIDs) by mouth or creams that can be rubbed on the skin over painful joints

  • Injections of corticosteroids into the joint

  • Injections of medicines that keep the immune system from attacking the joints and also help clear up the psoriasis rash

Doctors may prescribe physical therapy and exercises to help keep your joints moving.

When other treatments don't work, doctors may suggest surgery to replace a badly damaged joint with an artificial one.

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