5-hydroxy-tyrptophan (5-HTP) for depression

Posted on Sun, 22 Jul 12

Some 30 years ago studies of the dietary supplement 5-HTP suggested benefit in depressive disorders but this research came to a halt, perhaps by no coincidence, around the time that the first selective serotonin re-uptake inhibitor (SSRI), fluoxetine (Prozac) was approved in the United States.

Despite the lack of recent interest there have been at least 15 clinical studies of 5-HTP for depression conducted since the 1970s, including some 500 patients, which collectively show evidence of significant clinical improvements in depression (2). A comparative study also suggested better tolerance and lower side effects than fluoxetine (3).

In over 60 human clinical studies of 5-HTP there have been no reports of adverse effects or safety issues, and despite the suggestion that 5-HTP may interact with anti-depressant drugs to cause “serotonin syndrome” there has never been any reported cases documented, including in clinical studies where 5-HTP was given along with anti-depressant medications (4).

References:

1. Turner EH, Loftis JM, Blackwell AD. Serotonin a la carte: supplementation with the serotonin precursor 5-hydroxytryptophan. Pharmacol Ther. 2006 Mar;109(3):325-38.
2. Birdsall TC. 5-Hydroxytryptophan: a clinically-effective serotonin precursor. Altern Med Rev. 1998 Aug;3(4):271-80.
3. Poldinger W, Calanchini B, Schwarz W. A functional-dimensional approach to depression: serotonin deficiency as a target syndrome in a comparison of 5-hydroxytryptophan and fluvoxamine. Psychopathology 1991;24:53-81.
4. Das YT, Bagchi M, Bagchi D, Preuss HG. Safety of 5-hydroxy-L-tryptophan. Toxicol Lett. 2004 Apr 15;150(1):111-22.