Lol, I was just about to post up and be like "Salvia" but I honestly can't agree now that I think about it. For me, Phenibut is the worst drug I've ever taken, because it tried so hard to grab hold of me with its insanely addictive potential, and I was getting there...
But then I started taking kava, and I was like damn! This feels similar in ways but not super intense. I think that's what helped me stop taking Phenibut but I don't really know. I have really bad tinnitus and noticed that it got much worse from Pheni. Also, when I take any drug, I can always "taste it" in my head. Like, it's hard to explain.
I can taste the chemicals and all that, even in something as simple as Tylenol or Motrin. Pheni just had this citric, dirty diaper taste to it... I've never found anyone who describes this like I do. It could be due to synesthesia making my senses react differently to actually notice, because really I have no clue. I've never met another person who can relate on this, and this is precisely why I even quit drinking. I taste alcohol into the next day.
Seriously, do NOT fuck with Phenibut. Don't. Yes it has quite a wild fucking high but damn, it's so dangerous and addicting, and from what I've heard has quite possibly the worst drug withdrawals known to man, especially with the people who were taking really high doses daily.