Psoriatic arthritis is an autoimmune condition that affects the joints, skin, and other organs. It usually develops as a complication of psoriasis and causes many symptoms, including inflammation and tenderness of the joints and a reduced range of motion.

This article looks at what psoriatic arthritis is, its connection to psoriasis, and what causes the immune system to attack the body. It also provides information on how doctors diagnose and treat the condition.

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The immune system usually protects the body from infection and toxins. Occasionally, it mistakenly identifies healthy cells and tissue in the body as harmful and attacks them. This is known as an autoimmune disease.

Psoriatic arthritis is an autoimmune condition in which the immune system mistakenly identifies healthy joints as dangerous and attacks them, too.

It produces antibodies that attack and inflame the joints, leading to pain and swelling. It also affects other organs, such as the skin, nails, eyes, and gastrointestinal tract.

Psoriasis is also an autoimmune condition. It results when an overactive immune system causes a rapid increase in the production of skin cells.

Around 30% of people with psoriasis will also develop psoriatic arthritis. This means the majority of people with psoriasis do not go on to develop psoriatic arthritis.

Types of psoriasis include:

Learn more about the link between psoriasis and psoriatic arthritis.

No one knows exactly what causes the immune system to attack the healthy tissues, and according to the Arthritis Foundation, researchers are not entirely sure why some people go on to develop psoriatic arthritis.

However, they suggest that certain genes can make a person more likely to develop the condition. And certain other factors, such as an infection, stress, or injury, may trigger it.

The main symptoms of psoriatic arthritis include joint pain, stiffness, and swelling. This is a result of inflammation inside the joints, also known as inflammatory arthritis.

The most commonly affected joints include those of the:

  • neck
  • shoulders
  • elbows
  • base of the spine
  • wrists
  • fingers and thumbs
  • knees
  • ankles
  • toes

Other common symptoms of psoriatic arthritis include:

  • fatigue
  • reduced range of motion
  • pitted nails or nails that separate from the nail bed
  • tiredness and stiffness in the morning
  • uveitis, which is when the eye is painful and red


Psoriatic arthritis can also cause pain and swelling along the bones that form the joints. This results from inflammation of the connective tissue, or entheses.

The National Psoriasis Foundation notes that enthesitis affects approximately half of those with psoriatic arthritis. It most commonly occurs in the ankles, toes, and fingers. It can also affect the elbows, hips, chest, and knees.


Inflammation of the fingers or toes is called dactylitis.

This occurs in around 40% of people with psoriatic arthritis. It usually affects more than one digit and is not symmetrical.


Roughly 7–32% of people with psoriatic arthritis also experience inflammation of the spinal column, or spondylitis. This inflammation can cause stiffness and pain in the neck, lower back, and hips.

A person will need to consult a medical professional called a rheumatologist to diagnose psoriatic arthritis.

There is no specific diagnostic test for the condition. Instead, a rheumatologist will make a diagnosis based on a person’s symptoms and a physical examination.

They may also order blood tests to see if a person has elevated levels of certain proteins called anti-cyclic citrullinated peptide (anti-CCP) antibodies. These are associated with rheumatoid arthritis and can help doctors confirm or rule out that condition.

X-rays, ultrasounds, and MRIs can also help to confirm a diagnosis of psoriatic arthritis.

Psoriatic arthritis is one of the most destructive forms of arthritis, so it is essential to get a diagnosis and begin treatment as soon as possible to prevent permanent damage.

There is no cure for psoriatic arthritis, but many treatments can help to alleviate symptoms, prevent it from progressing, and reduce the impact on a person’s quality of life.


Treatments for psoriatic arthritis work toward:

  • preventing progression
  • reducing inflammation
  • restoring range of motion
  • alleviating pain
  • minimizing joint damage
  • treating skin symptoms

Treatment options for psoriatic arthritis include:

  • Nonsteroidal anti-inflammatory drugs (NSAIDs): These are typically oral medications but can be topical. They reduce inflammation in the body and can relieve pain.
  • Corticosteroids: A person can take these orally, or a doctor can inject them into specific joints in the body. They have many side effects, including swelling and easy bruising, and they can cause weak bones, so doctors try to prescribe the lowest possible dosage for the shortest time.
  • Disease-modifying antirheumatic drugs (DMARDs): These medications can prevent psoriatic arthritis from progressing. Traditional DMARDs are typically taken orally, whereas the biologic versions are administered via intravenous infusion or injection. They can block inflammatory processes and prevent inflammation from occurring.

Management and self-care

Management strategies for people with psoriatic arthritis include:

  • engaging in regular low impact exercise to keep the joints mobile
  • eating a diet rich in anti-inflammatory foods
  • using hot and cold packs to reduce inflammation
  • quitting smoking tobacco and drinking alcohol

If an individual’s psoriatic arthritis is affecting their work, they should consider asking their employer to make accommodations that help them perform their role efficiently.

Accommodations could include allowing a person to take frequent movement breaks or providing customized, ergonomic equipment that is easier to use.

The following are answers to some frequently asked questions about psoriatic arthritis.

Does psoriatic arthritis weaken the immune system?

Psoriatic arthritis itself does not weaken the immune system. However, doctors may prescribe immunosuppressive drugs to manage the condition. These drugs inhibit the activity of the immune system and can make a person more susceptible to a number of illnesses.

Is psoriatic arthritis a disability?

A person may be able to claim disability benefits in the United States if they meet the requirements under section 14.09, titled “Inflammatory Arthritis,” of the Disability Evaluation Under Social Security.

What autoimmune diseases are associated with psoriatic arthritis?

Studies have shown that there are certain autoimmune diseases that occur in people with psoriatic arthritis more frequently than in the general population.

These include conditions such as celiac disease, systemic lupus erythematosus, thyroid autoimmunity, and vitiligo.

Psoriatic arthritis is an autoimmune condition in which the immune system mistakenly attacks healthy joints, resulting in inflammation.

The main symptoms include pain, swelling, and stiffness in the joints due to inflammation.

A rheumatologist can help diagnose psoriatic arthritis based on a person’s symptoms, a physical examination, blood tests, and imaging tests.

Treatment aims to manage symptoms and prevent the condition from progressing.