Failure to detect p-methoxyphenylethylamine derivatives in human urine

Abstract

No positive evidence could be found for the appearance in urine from either normal people or schizophrenics of 3,4-dimethoxyphenylethylamine, p-methoxyphenylethylamine, 3,4-dimethoxyphenylacetic acid, or p-methoxyphenylacetic acid. It was confirmed that these amines when ingested are excreted largely as the acids so that failure to find the acids in urine in detectable amounts (10 μg/24 h) indicates that the amines, if present at all, would be far below the limits detectable by the methods used (5 μg/24 h). The discrepancy between this and previous reports may depend on the particular urine specimens studied but is more likely a reflection of resolution difficulties in gas, paper, and thin-layer chromatography. Ninety percent of the radioactivity of administered p-tyramine-2-14C was accounted for in the urine with no evidence of any p-methoxylated derivative. Various common foodstuffs do not contain detectable amounts of these p-methoxylated amines or acids.