psychomimetic
Bluelighter
well actually:
there's been some speculation that taking too much melatonin for an extended period of time can throw off your bodies natural production of the hormone.
Kava can be toxic to your liver as well if it is not prepared properly. The stems and leaves contain trace amounts of a hepatoxic chemical not found in the root, so unless you know that only the kava root extract has been used there is some chance for hepatoxicity.
I don't know of any adverse affects from valerian however.
that said, I doubt that the concentrations of any of the above compounds in any of these over the counter relaxation drinks/foods will have adverse effects unless you ate them nonstop everyday
Kava is liver toxic regardless of how its prepared I believe. But most of these drinks don't have Kava, and I don't think they'd hurt if you weren't drinking them all the time.
I've experienced down regulation like you say from melatonin, after a few weeks of taking it nightly it gave me bad insomnia if I skipped a dose. But that went away pretty quick and I wouldn't call it harmful, more natural down regulation from using a chemical sleep aid.
Either way, like you said and I have said, these won't hurt you unless you're eating them constantly, and even then they probably won't have very serious adverse effects.
