A person with psoriasis can have limited outdoor sun exposure as a treatment but only under the care of a dermatologist the national psoriasis foundation suggest starting with 5 10 minutes of. This is because the sun gives off a kind of light called ultraviolet uv light there are two types uva and uvb uva light by itself doesnt do much to ease psoriasis symptoms but uvb light can. The suns ultraviolet rays are made up of uva and uvb rays uvb rays are more effective at treating psoriasis symptoms because they slow the rapid rate of skin growth and shedding although. Most people who have psoriasis find that the sun helps to improve their skins appearance for some the change is dramatic with red scaly patches almost disappearing altogether during summer months in a warm climate in order to help clear psoriasis sun exposure needs to be spread over time