para-aminobenzoic acid (H2NC6H4COOH) (PABA) /per′ə·amē′nōbenzō″ik/ , a substance, often associated with the vitamin B complex, found in cereals, eggs, milk, and meat, and present in detectable amounts in blood, urine, spinal fluid, and sweat. It is widely used as a sunscreen that forms a partial chemical conjugation with constituents of the horny layer and resists removal by water and sweat. PABA is a sulfonamide antagonist and may be an effective agent for the treatment of scleroderma, dermatomyositis, and pemphigus.
