When people are diagnosed with psoriasis, it changes them physically because of the lesions that appear on the skin. But, just as importantly, it may influence how they work, play, view themselves and interact with others. What Causes Psoriasis? Psoriasis may be one of the oldest recorded skin conditions. It was probably first described around 35 AD. Some evidence indicates an even earlier date. Yet, until recently, little was known about psoriasis. While scientists still do not fully know what causes psoriasis, research has significantly advanced our understanding. One important breakthrough began with the discovery that kidney-transplant recipients who had psoriasis experienced clearing when taking cyclosporine. Since cyclosporine is a potent immunosuppressive medication, this indicates that the immune system is involved. Can Genetics Cause Psoriasis? Family History. Some people who have a family history of psoriasis never develop this condition. Research indicates that a “trigger” is needed. Stress, skin injuries, a strep infection, certain medications, and sunburn are some of the known potential triggers. Medications that can trigger psoriasis are anti-malarial drugs, beta-blockers (medication used to treat high blood pressure and heart conditions), and lithium. Dermatologists have seen psoriasis suddenly appear after a person takes one of these medications, gets a strep infection, or experiences another trigger. Phototherapy Treatment for Psoriasis Phototherapy involves exposing the skin to wavelengths of ultraviolet light under medical supervision. Treatments usually take place in a doctor's office or psoriasis clinic. However, it is possible to follow a treatment regimen at home with a unit prescribed by your doctor. The key to success with phototherapy is consistency. Is psoriasis contagious? No. You can't catch psoriasis from another person or give it to someone by touching them, and you can't spread it to other parts of your body. For years people with psoriasis had options that were either time consuming or had difficult side effects. However the new science of biologics is offering treatments that may help people not only manage their disease but also clear psoriasis for months and sometimes years.