Psoriasis is an immune-mediated disease, meaning that a dysfunctional immune system is a key cause of the disease. In the case of psoriasis, an overactive immune system can cause a rapid increase in skin cell production that leads to raised, scaly patches on the skin. These patches can be red in Caucasian skin and purple in skin of color. Many people report that psoriasis itches, burns and stings.
Psoriasis is not just a skin disease but a systemic one, which means it affects your whole body. It is associated with other serious health conditions, such as diabetes, heart disease and depression. If you develop a rash that doesn’t go away with an over-the-counter medication, you should contact your health care provider.
Psoriasis is also associated with psoriatic arthritis (PsA). PsA is a chronic, inflammatory disease of the joints and the places where tendons and ligaments connect to bone. Inflammation can lead to swelling, pain, fatigue and stiffness in the joints. Left untreated, PsA can cause permanent joint damage.