3,4,5-Trimethoxybenzoic acid, a new mescaline metabolite in humans

After ingestion of 400 mg of mescaline sulfate by human volunteers, 3,4,5-trimethoxybenzoic acid was isolated from urine and identified by gas chromatography-mass spectrometry. The amount of this anionic mescaline metabolite was found to be very low as compared with that of the well-konwn 3,4,5-trimethoxyphenylacetic acid. The significance of this finding is discussed.