It sounds like you are talking about something that is in fact available in the U.S. called 5HTP, also known as Tryptophan, which is found in turkeys, post baking. From what I understand, it was sold for many years in the U.S. then was pulled, probably by the FDA (Food and Drug Association) since they are not too keen on herbs or vitamins in this country. Anways, I believe it was pulled because some studies showed that taking the 5HTP affected one's serotonin levels in an unhealthy way. My naturopath, who originally proscribed it for me, said it is perfectly safe: it does not harm the body.I am not a doctor either, so I would encourage you to check with a health care provider before going out and buying it. I find 5HTP in an alternative pharmacy here in Seattle, Washington (Rainbow Natural Remedies) and have been taking it for a couple of years. Unfortunately, I don't find that it helps my IBS all that much, but it definitely helps me sleep better at night. Hope it helps.