5-htp

5-HTP (5-hydroxytryptophan) is a compound the body makes from the amino acid tryptophan. In the body it can be converted into serotonin (a chemical involved in mood and other functions), which in turn can be converted into melatonin. Sold as a dietary supplement, the 5-HTP in products is typically derived from the seeds of an African plant, Griffonia simplicifolia.

5-HTP is one of several substances the body can convert into melatonin. According to NCCIH, supplements of this type — including 5-HTP — have sedative effects, but it is unclear how they work and there is very limited data on their effects on insomnia, with little evidence from studies in people. NCCIH does not report that rigorous trials have established 5-HTP as an effective treatment for insomnia, depression, anxiety, weight loss, or any other condition. The other popular uses listed above reflect how the supplement is commonly marketed rather than uses confirmed by high-quality evidence. Overall, the evidence supporting these uses is limited, and 5-HTP should not be relied on in place of treatments shown to work.

There is no government-established standard dose, and the NCCIH page reviewed does not recommend a specific amount. Because 5-HTP affects serotonin and may interact with medications, talk to your doctor or pharmacist before taking it — especially if you take antidepressants or other prescription drugs, are pregnant or breastfeeding, or have a health condition.

5-HTP is chemically and biochemically related to L-tryptophan, a supplement that was discontinued in 1989 after an outbreak of eosinophilia-myalgia syndrome (EMS) — a rare disorder that can cause severe, disabling complications and even death — which was traced to contaminated synthetic L-tryptophan from a single manufacturer. Because of this relationship, 5-HTP has been watched closely for safety; NCCIH reports that extensive analyses of several sources of 5-HTP found no toxic contaminants like those linked to L-tryptophan, nor other significant impurities. Even so, dietary supplements are not evaluated by the FDA for safety and effectiveness before they are sold, so product quality can vary. Talk to your healthcare provider before use.

The NCCIH page reviewed does not list specific side effects for 5-HTP. Because 5-HTP can be converted into serotonin, having too much serotonin is a theoretical concern, particularly if it is combined with other substances that raise serotonin. Stop use and seek medical advice if you notice unusual or worrying symptoms, and discuss potential side effects with a clinician before starting.

Because 5-HTP can be converted into serotonin in the body, combining it with antidepressants or other medicines and supplements that also affect serotonin could in theory lead to excess serotonin. The NCCIH page reviewed does not detail specific drug interactions for 5-HTP, so this is a precaution rather than a documented interaction. Tell your doctor or pharmacist about all medications and supplements you take before using 5-HTP, particularly antidepressants.