The exact cause of psoriasis isn't known.
Doctors believe that the Reference immune system Opens New Window overreacts, causing inflammation and flaking of skin.
Many scientists believe that psoriasis can be inherited. About one-third of people who have psoriasis have one or more family members with the condition.Reference 1 But it isn't clear that genetic factors alone determine whether you get psoriasis.
Psoriasis isn't contagious—it can't be spread by touch from person to person.
|By:||Reference Healthwise Staff||Last Revised: Reference January 9, 2012|
|Medical Review:||Reference Adam Husney, MD - Family Medicine
Reference Amy McMichael, MD - Dermatology