Health Conditions

What causes it?

Currently, researchers believe that the body's own defense system (the immune system) may send out false signals that cause the overgrowth of skin cells in individuals with psoriasis. In individuals without psoriasis, skin cells mature and are shed about every 28 days. In individuals with psoriasis, the skin cells move rapidly to the skin's surface in 3 to 6 days. This rapid production of skin cells does not allow time for the body to shed the cells, resulting in the formation of patches on the skin's surface. Certain individuals may have inherited genes that make them more likely to develop psoriasis, but not all individuals who have these genes will develop psoriasis. Often, certain triggers set these genes in motion.

Potential triggers may include:

• Emotional stress caused by a job or event at home or school

• Injury to the skin, such as cuts, burns or sunburns, rashes, insect bites

• Certain infections (upper respiratory infections like strep throat)

• Various prescription drugs (lithium, propranolol, quinidine, and indomethacin)

• Alcohol

• Smoking

• Weather (cold temperatures often worsen psoriasis)