Numerous factors contribute to the onset and exacerbation of psoriasis. Genetic risk factors include HLA-Cw6 and mutations in the caspase recruitment domain family member 14 gene, CARD14. Environmental risk factors, including infectious diseases, medications, and lifestyle, also have been implicated. It is important for clinicians to be aware of these risk factors and triggers because they might provide insight into the pathogenesis of psoriasis as well as help patients understand more about their disease.