Phenibut HCL is VERY acidic, and can cause gastric issues for some. It's never been a problem for me.
As for waiting to redose for the last dose to not affect you... I would not take it any more than every 3 days. A full dose will last over 24 hours. I usually take it around noon or maybe up to as ;late as 3pm, and still feel it quite nicely when I wake up in the morning... it lasts through most of the next day.
It's tricky to dose right... not quite enough, and it's subtle or even doesn't seem to do anything. A little too much, and it can be pretty unpleasant. You have to find your sweet spot, but since it takes so long to reach full effect, it takes some trial and error over a number of tries, usually, unless you get lucky.
A lot of people either think it does nothing to them, or hate it because they took too much their first time. There is an art to dosing phenibut.
I actually wrote a user guide/trip report for it years ago, it explains how to find your ideal dose:
Phenibut: A Comprehensive Long-Term Synopsis and Usage Guide by Xorkoth I first encountered phenibut in 2006. I was a member of a bodybuilding forum, not that I did any bodybuilding whatsoever (indeed, at the time I had virtually no upper body strength and had never been to a gym). I...
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