5-HTP

5-HTP (5-hydroxytryptophan) is a type of chemical known as an amino acid. It is chemically similar to another amino acid, tryptophan. 5-HTP is sometimes recommended for depression as well as for many other conditions. Tryptophan itself was sold in the past, and contaminated batches produced a serious condition known as eosinophilia-myalgia syndrome. One study indicates that 5-HTP contains the same contaminant. It would be safest to avoid 5-HTP on the basis of this information.