Products with 5-HTP (short for 5-hydroxytryptophan) are promoted for a variety of conditions, including depression, anxiety, appetite control, fibromyalgia, and sleep disorders. The human body makes 5-HTP from the amino acid tryptophan, but 5-HTP can also be produced commercially by extracting it from the seeds of the Griffonia simplicifolia plant. The body converts 5-HTP into serotonin, a substance that serves many functions related to mood, sleep, appetite, and pain sensation.

Although some research shows that 5-HTP supplements may affect symptoms of depression, the verdict is still out. Also, there isn’t enough evidence to show it’s effective for appetite control, sleep disorders, fibromyalgia, or other health conditions.

5-HTP supplements have been associated with a serious health condition called eosinophilia myalgia syndrome (EMS), but this is likely due to a contaminant in the products. A small number of cases were reported, but it turned out to be L-tryptophan supplements that were associated with the EMS, and FDA pulled those products from the market. If you experience any adverse events after taking products containing either 5-HTP or L-tryptophan, immediately see your doctor. Also, if you are taking any medications for depression, high blood pressure, and/or diabetes, talk with your doctor about potential interactions with 5-HTP supplements. 

Updated 11 December 2015


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