I have a feeling this particular substance will end up controlled and scheduled, or possibly banned.
I've used it, and I can assure anyone that the hangover from taking 4 grams of this stuff (2 grams in the morning and 2 grams about 2 hours before bed) is almost unbearable.
Woke up the following morning, and for the next few hours or so I felt like I had the flu, puking, nausea, dizziness, feeling like the room was spinning around me, and then after that the anxiety was disgusting. I thought I was in trouble at work or something.
Won't be touching this shit again. Alcohol is much more forgiving, even GHB is more forgiving than Phenibut.
Can you O/D on Phenibut? I can't say for certain but I wouldn't be betting on it. If you took a whole heap of this stuff thinking it's safe, and then decided to drop a long-acting benzo (ie, clonazepam) or a long-acting opiate (ie, methadone) there's a good chance you'd end up wearing a toe tag. I got 125 grams of this and figured it would be a good anxiolytic, which indeed it is, but it's no different to barbs or alcohol, it works for a day or so then suddenly stops. I won't throw away the rest, because there are times when using it for anxiety is imperative and I know people who are alcoholics and I could offer this to them with some very detailed advice on dosing etc, but for every day anxiety? Not a chance!
VERY good for alcohol withdrawal, a friend used it to ditch the booze and it worked for him. He said the same thing about it as I've said, the stuff is a big NO NO for recreational use. Only useful really for alcohol withdrawal and little else. Baclofen is also good for that too. As an anxiolytic there are better drugs - even barbiturates are better than this stuff and I don't recommend them for anxiety either. A short acting benzo does wonders for transient anxiety, but of course, don't use them everyday either or you'll end up with similar problems.