Psoralen

Part of speech: noun

Definitions

1. A naturally occurring furocoumarin compound that makes skin more sensitive to ultraviolet light and is used in phototherapy for conditions such as psoriasis
2. A plant-derived chemical that, when combined with ultraviolet radiation, is used medically to treat certain skin diseases like vitiligo and psoriasis
3. A photosensitizing substance found in certain plants that is applied with or taken before light exposure to help manage serious skin disorders

Etymology: Psoralen is a compound named for the plant genus "Psoralea", a group of legumes whose name comes from Greek "psōraleos", meaning "scabby" or "mangy", a reference to the rough, scurfy look of the plants' leaves and stems. The chemical was named by analogy with that genus, since several of these plant compounds were first isolated from it. The substance matters because it makes skin respond to ultraviolet light. Psoralens bind to DNA when activated by UVA light, which is why they are used in photochemotherapy for skin conditions such as psoriasis and vitiligo. The name thus links a plant's unflattering appearance to a modern medical treatment.

Synonyms: furocoumarin