important ammendment
one more thing, I strongly recommend you wait until the zoloft is completely out of your system before taking l-tryptophan. I'm not sure how 5htp works in regards to such things, but I can tell you that I actually tried to take l-tryptophan while I was on zoloft and it caused some gnarly side effects.. it made me jittery as well as other nastiness. the brain doesn't seem to like both an ssri and tryptophan supplement in your system at the same time. I have also read the exact same stories from others and heard such things from a close friend who also tried to take it while on an ssri.
I'm not completely sure if/to what extent "half life" is prolonged when you have been on it for years..
I'd say, to be safe, don't take tryptophan until about a week after you stop zoloft completely. :)
granted, this is just a super anal precaution as the badness I experienced was while on my full does of zoloft and taking a
sizable dose of tryptophan..
but better safe than sorry and it would be unfortunate if you decided you didn't like the l-tryptophan under false pretenses..
:)