5-HTP (short for 5-hydroxytryptophan) is a substance made by the human body from the amino acid tryptophan. 5-HTP also can be extracted from the seeds of the Griffonia simplicifolia plant. Whether it’s produced by the body itself or consumed in the form of a dietary supplement, the body converts 5-HTP to the neurotransmitter serotonin, a chemical that serves many functions related to mood, sleep, appetite, and pain sensation. 

The latest research suggests 5-HTP might be effective for depression, but there is not yet enough reliable evidence to support its use for any specific purpose. 

Is 5-HTP an effective dietary supplement ingredient?

The latest research shows that 5-HTP can improve symptoms of depression when taken by itself. Still, many of these studies are relatively weak, and more research is needed to confirm these findings, as well as determine the optimal dose of 5-HTP for depression. 

However, most dietary supplements containing 5-HTP are marketed for sleep, mood, relaxation, weight loss, and energy. Currently, there isn’t enough reliable scientific evidence to conclude that 5-HTP is effective for any of these purposes.

Can 5-HTP supplements negatively impact your health?

Side effects associated with 5-HTP are usually minor and include headache, insomnia, heart palpitations, and gastrointestinal symptoms such as nausea. More severe adverse effects, including mania, have been reported in those taking 5-HTP supplements along with certain prescription antidepressants.

5-HTP can interact with some medications, including ones used to treat depression, high blood pressure, and diabetes. If you are taking medications for any of these, talk with your doctor about potential interactions before taking any supplement containing 5-HTP.

5-HTP supplements have been associated with a serious health condition called eosinophilia myalgia syndrome (EMS), but it turned out to be linked to L-tryptophan in the supplements, and FDA pulled the products in question from the market. However, if you experience any adverse events after taking supplements containing either 5-HTP or L-tryptophan, immediately see your doctor.

Is 5-HTP safe for use by Military Service Members?

5-HTP is not prohibited for use by Military Service Members, and it should not cause a positive result on a routine military drug test. However, 5-HTP can cause drowsiness, so it is of potential concern especially for those on flight duty. If you’re on flight duty, follow the guidance of your flight surgeon regarding supplement use.


Updated 1 February 2021


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