About Psoriatic Arthritis

Overview: What is Psoriatic Arthritis?

Psoriatic arthritis (PsA) is a chronic (long-lasting or recurring) disease related to the immune system. It causes swelling, pain, and stiffness in your joints and entheses (places where tendons and ligaments connect to bones). Psoriatic arthritis can develop at any age.[1] Psoriatic arthritis can occur regardless of the severity of psoriasis (mild, moderate, or severe).

Roughly 1 in 3 people living with psoriasis also have psoriatic arthritis [2]; typically, with psoriasis developing before psoriatic arthritis.[1] While as many as 2.4 million Americans live with psoriatic arthritis, more than 15% of people living with psoriasis may also have undiagnosed psoriatic arthritis.[3]

Psoriatic arthritis in fingers

Symptoms

Signs of psoriatic arthritis include:

  • Pain, swelling, or stiffness in 1 or more joints
  • Morning joint stiffness (joint pain that is worse in the morning or after inactivity)
  • Joints that are red, discolored, or warm to the touch
  • Frequent joint tenderness or stiffness
  • Dactylitis (sausage-like swelling in 1 or more of the fingers or toes)
  • Pain in and around the feet and ankles
  • Changes to the nails, such as pitting or separation from the nail bed
  • Pain in the lower back, above the tailbone
  • Fatigue

Just like psoriasis, psoriatic arthritis can range from mild to severe. There is little connection between psoriasis severity and PsA severity. You could have few skin lesions, but many joints affected by arthritis.

Mild psoriatic arthritis is sometimes referred to as oligoarticular, meaning it affects 4 or fewer joints in the body. More severe psoriatic arthritis is often called polyarticular, meaning it affects 5 or more joints. Regardless of the severity, psoriatic arthritis can be very painful and can affect the ability to do daily tasks and move comfortably.

Dactylitis - a symptom of psoriatic arthritis

Dactylitis

Enthesitis - a symptom of psoriatic arthritis

Enthesitis

Spondylitis - a symptom of psoriatic arthritis

Spondylitis

Domains of Psoriatic Arthritis

PsA can occur in any joint or wherever your ligaments and tendons connect to bone. You may experience PsA symptoms in certain areas of your body, which are commonly called domains. The six domains of psoriatic arthritis include spondylitis, enthesitis, dactylitis, peripheral arthritis, psoriasis, and nail changes.

Causes and Triggers

Like psoriasis, scientists do not know all the causes of psoriatic arthritis. The immune system and genetics play a role in the development of psoriatic arthritis. The chance of developing psoriatic arthritis is higher for people who have a family member living with psoriatic arthritis. [2] For others, they may develop psoriatic arthritis because of an overactive immune system response triggered by a number of factors.

A psoriatic arthritis flare may include new or increased joint pain, tenderness, swelling, or stiffness. Flares can last for different amounts of time and differ in level of severity.

Triggers are different from person to person. What may worsen your psoriatic arthritis might not have any impact on someone else. Common psoriatic disease triggers include:

  • Stress
  • Smoking or alcohol use
  • Injuries or trauma to the skin or joints
  • Illness, such as infections
  • Certain medications
  • Changes in weather
  • Diet

Learn more about triggers and flares by requesting a free Flare Guide and Symptom Tracker.

Diagnosis

Unfortunately, there is no definitive diagnostic test for psoriatic arthritis. The diagnosis is made mostly by your doctor’s observations and by a process of elimination. For example, the symptoms of psoriatic arthritis are similar to those of rheumatoid arthritis, gout, and reactive arthritis.   

Psoriatic arthritis is best diagnosed and treated by a rheumatologist (a doctor who specializes in the diagnosis and treatment of diseases that affect the muscles, joints, and bones and related immune-mediated conditions). Early diagnosis and treatment can not only help relieve symptoms but may also help prevent permanent joint damage.

To make a diagnosis of psoriatic arthritis, your rheumatologist may consider several factors:

  • Examination of your skin, joints, and nails
  • X-rays
  • MRI scans
  • Ultrasounds
  • Blood tests

Each step will help to rule out other conditions and lead to an accurate diagnosis.

Until a diagnostic tool for psoriatic arthritis is developed, it may take a few appointments with a rheumatologist to get the correct diagnosis. Although it may take time, getting an accurate diagnosis is very important for managing your symptoms, preventing permanent joint damage, and caring for your overall health.

Screening for Psoriatic Arthritis

If you think you may have psoriatic arthritis, you can learn more by taking a short 5-question quiz. You can share the results with your health care provider. The quiz is based on the Psoriasis Epidemiology Screening Tool (PEST).

Treatment & Management

Treating psoriatic arthritis is important to help lessen pain, reduce inflammation, help keep joints healthy, and possibly prevent permanent joint damage. Generally, biologic, biosimilar, and oral systemic treatments are prescribed to treat psoriatic arthritis.

  • Biologics and biosimilars are medications made from living cells that are given as an injection or intravenous (IV) infusion. Biosimilars are medications that are modeled after a biologic that has already been approved by the FDA. They target specific proteins in the immune system that play a role in psoriatic arthritis.
  • Oral systemic treatments are medications taken by mouth, most often in the form of a pill. There are several oral systemic treatment options that treat psoriatic arthritis. These treatments work by targeting the immune system.

Prevention

There is no known way to prevent the onset of psoriatic arthritis, however, there are many ways that you can manage your triggers to reduce flares.

Outlook/Prognosis

Psoriatic disease is lifelong, and symptoms may resolve and recur throughout the lifetime.

While there is no cure for psoriatic arthritis, treatments today are more effective than ever before and research into new treatments, as well as a cure, is ongoing. Treating psoriatic arthritis can help improve symptoms, prevent joint damage, and may decrease the associated inflammation that can lead to comorbidities such as heart disease, diabetes, anxiety, and depression.

Life with Psoriatic Arthritis

As with other chronic diseases, psoriatic arthritis may affect a variety of areas of your life including your physical and mental health, participation in social activities, and your work life. Learn about the importance of physical activity, pain management, and stress reduction for living with psoriatic arthritis as well as tips on how to manage your disease on the job.

Additional Resources

The hands of a man with psoriatic arthritis on a wooden table, showing deformities in the fingers.

Psoriatic Arthritis or Rheumatoid Arthritis?

Dr. Cassandra Calabrese explains the similarities and differences between PsA and RA.

Read more
A woman with skin of color is studying with a laptop computer.

What is the Right Treatment for PsA?

We are here to help you navigate your psoriatic arthritis treatment options.

Read more
Stephen in a kayak on a river

Understanding Inflammation

Why does it happen? And how do you keep it under control?

Read more

Request Your PsA E-Kit

Learn about common symptoms of PsA, treatment options, and assistive devices.

Request your free e-kit

Last updated on 4/21/2025 by the National Psoriasis Foundation.

References

  1. Ritchlin CT, Colbert RA, Gladman DD. Psoriatic Arthritis [published correction appears in N Engl J Med. 2017 May 25;376(21):2097]. N Engl J Med. 2017;376(10):957-970. doi:10.1056/NEJMra1505557
  2. Mease PJ, Gladman DD, Papp KA, et al. Prevalence of rheumatologist-diagnosed psoriatic arthritis in patients with psoriasis in European/North American dermatology clinics. J Am Acad Dermatol. 2013;69(5):729-735. doi:10.1016/j.jaad.2013.07.023
  3. Villani AP, Rouzaud M, Sevrain M, et al. Prevalence of undiagnosed psoriatic arthritis among psoriasis patients: Systematic review and meta-analysis. J Am Acad Dermatol. 2015;73(2):242-248. doi:10.1016/j.jaad.2015.05.001

Stay in the Know

Expert tips, can’t-miss events, and the latest news, straight to your inbox.

National Health Council Standards of ExcellenceCharity Navigator

Copyright © 1996-2025 National Psoriasis Foundation/USA


The National Psoriasis Foundation is a qualified 501(c)(3) EIN 93-0571472.


Duplication, rebroadcast, republication, or other use of content appearing on this website is prohibited without written permission of the National Psoriasis Foundation (NPF).


NPF does not endorse or accept any responsibility for the content of external websites.


NPF does not endorse any specific treatments or medications for psoriasis and psoriatic arthritis.

We use cookies to offer you a better experience and analyze our site traffic. By continuing to use this website, you consent to the use of cookies in accordance with our Privacy Policy.