Topical administration of hematoporphyrin derivative and red light irradiation. A therapeutic approach in psoriasis

A controlled trial of topical photochemotherapy of plaque-type psoriasis using hematoporphyrin derivative (HPD) in combination with red light (590-700 nm) was performed on 8 patients. For each patient HPD (1%) in N-methylpyrrolidone was applied on one psoriatic patch, only the vehicle being applied on the control one. Both patches were daily irradiated with incoherent red light (60 J/cm2/day) for a week. Comparative evaluation of clinical and histologic results are discussed