Psoriatic arthritis is a form of arthritis that sometimes develops in people who have a skin condition called psoriasis. It causes swelling and pain in joints—most often in the fingers and toes—in an irregular pattern that may be different on opposite sides of the body.

Treatment for psoriatic arthritis includes pain medicine, patient education, and physical and occupational therapy. Severe cases may require more powerful medicine, such as biologic drugs, or steroid injections.