👉 Psoriasis is an autoimmune disorder that causes skin cells to grow on and around the scalp, causing redness, itching, and scaling. Psoriasis typically starts in children who have a family history of psoriasis or other autoimmune diseases. It can also affect adults and cause noticeable changes in body texture, such as dryness or flaking. Psoriasis is often treated with medications that suppress the immune system to reduce inflammation and help prevent further damage.