I know this is an older thread, I haven't been around BL for many many years, but I wanted to add a few things here in case anyone is still browsing for info on these substances... I'm quite clueless when it comes to chemistry or the molecular make up of drugs, but I'm very familiar with pharmaceuticals, nootropics, RC's, and their effects, simply from dedicating 15 years of my life to being the "best" poly-sub addict I could be. When it comes to Phenibut, I haven't had experience with it for roughly 10 years, and I remember enjoying it, but replacing it quickly with 1,4 BDO, which I loved. Until, I blacked out, nearly emptied my bank account with a few tweakers I hardly knew, let them borrow my car, stay at my place etc, and on the next occasion, OD'd, and never touched the stuff again. But that stuff, IMO, was incredible. I was also on suboxone, klonopin, and IV meth at the time. Anyways, I've been experimenting with "f-phenibut" FAA off and on for the last month or 2, but haven't been stable enough on/off of everything else I take to do some solid research or even an effective trip report. But the discussion over whether this stuff is essentially, literally, or effectively f-baclofen, interests me quite a bit. And in my experience, there may be subjective similarities to regular baclofen and this f-phen/bac, but I have extensive experience with Rx baclofen, and I don't think we should be using it as way to compare dosage, tolerance, dependence, withdrawal, etc. I'll speak mainly to baclofen (Rx), but I was prescribed 80mg/day, have taken well over 200mg, as well as overdosed on it. I got good anxiety relief, social and generalized, from 80-100mg of baclofen, but even at high doses, I never felt the same type of effects as I have on f-phen, although it seems to be much more hit or miss, dose dependent, etc. Baclofen has very little dependence and tolerance issues even at daily 80mg+ doses, it also, IME, doesn't have a compulsive or redosing element to it much at all. It has been used by medical professionals, in the 100mg+ /day range to treat and "cure" alcoholism, and in my experience, I essentially forgot about drinking, had no cravings, and that wasn't even my intent, just a positive bonus effect. I will also add that I did legit OD on baclofen, but, I didn't get carried away in the traditional manner. I was withdrawaling from H, Meth, and probably alcohol as well, and have partial-complex seizure disorder, and mid WD, I began to feel like I was going to have some type of seizure, and the last thing I remember was looking for something to prevent it/help the WD, etc... turns out, I swallowed my entire bottle of baclofen, so at least 4000mg (yes 4 GRAMS or more). I have no memory of it, but I basically amplified the seizure activity and went into an overdose induced seizure and psychosis and I wound up with 7 paramedics needed to get me into an ambulance, and according to the hospital, I came in as the most extreme case they'd ever seen, and attempted to treat. I was not unconscious but apparently they assumed i was on "bathsalts", PCP, etc, and it took them several hours to even succeed at RSI (intubation), and they eventually got me down and on a fentanyl,versed, and ketamine drip, in a medically induced coma, but that only lasted a few days and I came to while intubated, with no memory or clue where I was or what was happening, basically the worst thing I've ever experienced. But, now I'm telling war stories so I digress. Point is, while the molecular structures of baclofen and f-phenibut are essentially the same, I do not believe they should be compared or considered to be essentially the same in any other definitive way. Sorry for the long rant, Hope this helps.
TLDR; I have considerable experience with Baclofen, and gaba-ergics in general, and as I am currently researching f-phenibut, I just wanted to add to this discussion by saying I do not think comparing f-phenibut to baclofen for the purposes of dosing, effect profile, side effects, tolerance/dependence, or any other objective comparison measures. And from my experience, there does not seem to be any point at which the 2 are indistinguishable from each other. I think it is only safe to treat f-phenibut (f-baclofen, whatever you want to call it) as it's own substance with it's own properties. I'd love to hear any further experiences from recent years, if anyone is still researching or using this chem in any way. It's good to be back on BL!