Prostaglandins E2, F2α and arachidonic acid levels in irradiated and unirradiated skin of psoriatic patients receiving PUVA treatment.

Arachidonic acid and prostaglandins E&sub2; and F&sub23; are known to be elevated in exudate from healthy human skin during the first 24 hours after exposure to three times the minimal erythema dose of ultraviolet light. Indomethacin reduces the erythema and prostaglandin concentrations with both types of ultraviolet radiation but does not influence photochemotherapy (PUVA) erythema. Furthermore the pharmacological events occurring in PUVA treated skin are unknown. PUVA, in contrast to ultraviolet radiation induced erythema is not associated with increased concentrations of arachidonic acid and a role for these agents in the photochemotherapy of psoriasis seems unlikely.