2,3-Dihydroxybenzoic acid is a product of human aspirin metabolism.

2,3-Dihydroxybenzoic acid is present in blood plasma and urine of healthy human volunteers after aspirin ingestion. Its identity has been confirmed by mass spectrometry and by electrochemical analysis. Methods for its identification and measurement are described. The concentration of 2,3-dihydroxybenzoic acid is much lower than that of 2,5-dihydroxybenzoic acid, salicylic acid or salicyluric acid.