http://en.wikipedia.org/wiki/5-Hydroxytryptophan

I'm confused by this. Can anyone help me understand if it's possible that occasionally taking a couple hundred mg of 5-HTP will cause heart valve damage. Thank you

The first study talks about long-term administration (90 days) in rats.

Gustafsson BI, Tømmerås K, Nordrum I, Loennechen JP, Brunsvik A, Solligård E, Fossmark R, Bakke I, Syversen U, Waldum H (March 2005). "Long-term serotonin administration induces heart valve disease in rats". Circulation 111 (12): 1517–22. doi:10.1161/01.CIR.0000159356.42064.48. PMID 15781732.

The second one is free. G33k on.

http://www.ncbi.nlm.nih....pmc/articles/PMC1850896/
Xu J, Jian B, Chu R, Lu Z, Li Q, Dunlop J, Rosenzweig-Lipson S, McGonigle P, Levy RJ, Liang B (December 2002). "Serotonin mechanisms in heart valve disease II: the 5-HT2 receptor and its signaling pathway in aortic valve interstitial cells". Am. J. Pathol. 161 (6): 2209–18. PMID 12466135. PMC 1850896.

Don't know much about the 5-HTP effects but I wouldn't conlucude such thing (danger when occasionally ingesting) after quickly skimming through the summary of the first study. The second one is too much fo' me.

I would be more concern about possible interaction with harmalas TBH. serotonin syndrome ... Yuck!

in my case apparently not

Taking 5HTP occasionally is not a major worry with regards to the heart.Taking lots, every day, is a different matter I suspect.There is a type of cancer called the Carcinoid Syndrome which is largely characterised by excessive serotonin production which quite often causes heart valve problems, usually affecting the right-sided valves (tricuspid, pulmonary) but on rare occasions does effect the aortic and mitral (Left-sided) valves-but only if you have a little hole in the heart called the Foramen Ovale.We all have one but in the majority of people it closes around the time of birth.

From what I can gather of the second paper, the gist of it is that 5-HTP causes activity at receptors that can stimulate the development of plaque and collagen on mostly the right-side heart valves, but the paper still does not offer any concrete conclusions besides that it is probably bad to be chronically ingesting 5-HTP for prolonged periods of time and that left-side heart valves can possibly be damaged as well if 5-HTP is used chronically with MAOI's.

not to do with the OP's question, and I won't go into too much detail, but my experience taking 5-HTP to help with depression, i had strange sleep paralysis like side effects, like a living nightmare! occasionally, when falling asleep i would still be awake and conscious to a degree, without having any control over my body (couldn't move a muscle), and not being able to open my eyes. I'd have these intense hallucinations / delusions that there was somebody in my house / room with very negative intentions, standing over me but i couldn't move. couldn't even make a noise, ie. full on paralysis! scary stuff!