Psoriasis is a common, chronic, scaly rash that affects people of all ages (about 2% of the population). Furthermore, psoriasis is usually passed down genetically. Psoriasis is also influenced by many environmental factors. It is not contagious and is not due to an allergy.
The most common ages for psoriasis to first appear are in the late teens and in the 50s. The average age for Psoriasis to appear is around 28 years old. It affects men and women equally, although in children, girls are more commonly affected than boys.
Psoriasis is often so mild it is barely noticed by the affected person, but it can occasionally so severe the patient must be admitted to hospital for treatment. In fact, many mild cases can be described as a minor sunburn. It may or may not be itchy.