Para-aminobenzoic acid (PABA)

Para-aminobenzoic acid (PABA) is a chemical found in the folic acid vitamin and also in several foods including grains, eggs, milk, and meat.

PABA is taken by mouth for skin conditions including vitiligo, pemphigus, dermatomyositis, morphea, lymphoblastoma cutis, Peyronie's disease, and scleroderma. PABA is also used to treat infertility in women, arthritis, "tired blood" (anemia), rheumatic fever, constipation, systemic lupus erythematosus (SLE), and headaches. It is also used to darken gray hair, prevent hair loss, make skin look younger, and prevent sunburn.

PABA is best known as a sunscreen that is applied to the skin (used topically).

PABA doesn't seem to be taken by mouth as often as it used to be, possibly because some people question its safety and effectiveness.