Menu Healthy Lifestyle Diseases & Conditions First Aid Symptoms Tests & Procedures Videos Definitions FAQs PsoriasisUpdated: 2020-05-02OverviewPsoriasis is a skin condition. It's thought to be an immune system problem. Triggers include infections, stress, and cold.SymptomsIt causes skin cells to build up, forming scales and itchy, dry patches.TreatmentsTreatments aim to stop skin cells from growing so quickly and remove scales. Topical ointments, light therapy, and medications can offer relief. © 1998-2022 Mayo Foundation for Medical Education and Research(MFMER). All rights reserved. Terms of Use