PSORIASIS Psoriasis is a long-term disorder in which skin cells reproduce too rapidly, causing red, thickened patches. Psoriasis tends to recur in attacks, which may be triggered by factors such as infection, injury, stress, or certain medications.
In the most common type, called plaque psoriasis, red, flaky patches (plaques) covered in silver scales appear, usually on the elbows, knees, and scalp, which are itchy and sore. In guttate psoriasis, small, scaly, red patches occur all over the body.
In flexural psoriasis, large, smooth, red patches develop in skin folds. Psoriasis may also affect the nails, which become pitted, discolored, and loose. Psoriasis may also cause psoriatic arthritis .
Psoriasis can often be improved by topical treatments with corticosteroids, emollients, vitamin D analogues (forms of vitamin D), coal-tar preparations, or dithranol preparations. Ultraviolet light therapy may also help. If such treatments are ineffective, tablets or injected medication may be used.