I read somewhere that taking some form of niacin (niacin, niacinamide, inositol hexanicotinate) with it makes it work better. Your body uses tryptophan to make niacin. If you flood your body with niacin, you spare the tryptophan. The tryptophan can then be used to make serotonin. Something like that, anyway. I now take 3 grams niacinamide daily. I find it to be better for me, long term, than the 5htp was, but that may be because of niacinamide's actions on GABA ((mega doses, over a long time, are supposed to be kinda sorta benzodiazepine-ish)).

Hope this helps.