Photochemotherapy for psoriasis with orally administered methoxsalen
K. W. Wolff, T. B. Fitzpatrick, J. A. Parrish, F. Gschnait, B. Gilchrest, H. Honigsmann, M. A. Pathak and L. Tannenbaum
Photochemotherapy denotes a therapeutic approach that is based on the
interaction of light and a photoactive drug. This study describes the
efficacy of photochemotherapy, using orally administered methoxsalen and
long-wave ultraviolet light in 91 patients with severe, generalized
psoriasis. Oral administration of methoxsalen was followed by exposure to a
high-intensity long-wave ultraviolet light source, emitting a continuous
spectrum between 320 and 390 nm (peak, 365 nm) and an energy of 5.6 to 7.5
mw/sq cm at 15 cm. There was complete clearing of 82 patients (90%), a 90%
to 100% clearing in seven (8%), and a satisfactory improvement in two (2%).
A paired comparison study in 54 patients showed photochemotherapy to be far
more effective than ultraviolet light emitted by fluorescent bulbs or a
xenon source. Eighty-five percent of the patients receiving outpatient
maintenance treatment have remained in remission for periods up to 400
days.
