ABSTRACT
The topical treatment of psoriasis is firstline and mainstream in the United States. Topical agents are generally considered to be easy to administer, costeffective, safe, and acceptable to patients. They are typically prescribed as the initial treatment when plaque psoriasis affects less than 20% of the body surface. However, for patients with moderate to severe disease, topical agents may not be appropriate or acceptable. Application to a large body surface area is time-consuming, expensive, and puts the patient at increased risk for systemic adverse effects. Cutaneous side effects may be intolerable over a large area. Topical agents can be messy and may look or feel unacceptable to the patient. Using quality-of-life parameters, response to treatment has been used to define severity; by this definition severe psoriasis does not have a satisfactory response to treatments that have minimal risks (1). Thus moderate-tosevere psoriasis may, by definition, be moderate to severe because it does not respond to topical agents.
