This review illustrates that UVB
phototherapy is not only a time-honored treatment, but also highly effective for widespread
psoriasis. Treatment parameters include the frequency of irradiation, initial dose based on skin type or MED, increments of UV exposure, and maintenance schedule, according to defined protocols. UVB can be combined with adjunctive topical or systemic
therapies either concomitantly or sequentially for additive effect. The use of various therapeutic modalities, including UVB
phototherapy on a rotational basis, has been advocated for long-term control with reduced toxicity. UVB with
emollients in an erythemogenic dosage schedule is as effective as PUVA for clearing of
psoriasis in selected fair-skinned patients. Unlike PUVA, it does not involve a systemic photosensitizing
drug and is relatively convenient and simple to use. UVB is the most commonly used
therapy by dermatologists for widespread
psoriasis that does not respond to topical
therapies; it has been shown to be one of the most cost-effective
therapies for widespread
psoriasis.