I recently ordered phenibut from liftmode.com and have used it several times. Here is my review:
Some background info: I don't drink alcohol or use caffeine and I am usually very sensitive to chemical substances of any kind. Most any drug has an effect on me. I am currently only taking an SSRI and Wellbutrin as my meds for social anxiety.
The first time I used phenibut, I took 1000 mg in the morning on an empty stomach. I waited to feel something, but I could not be certain I felt anything at all until 12 hours later, when my head became very heavy and I became sleepy. The next day, around noon, I started feeling something like a hangover. I also became very anxious. This lasted until the evening. The next day I was fine.
I decided I had taken too high a dose the first time, so a week later, I took 500 mg in the morning on an empty stomach. Again, I waited, but I did not feel any noticeable effect. Around 12 hours later, I felt a little sleepy; not as much as last time, but definitely caused by the phenibut. The next day around 10:00 in the morning I began feeling a mini-hangover. It was not bad and only lasted 4-5 hours and I was fine after that.
The last variable I tried to alter was the timing of the dose. A week after the 500 mg trial, I took another 500 mg dose, this time before going to sleep. I did not notice anything different about my sleep during the night, but in the morning I did notice I was still very sleepy and had difficulty getting up. I did not notice anything during the day. I also did not notice any hangover effect, but it may have occured during sleep the next night.
I was surprised that phenibut did so little for me, since I usually respond strongly to chemical substances. I start feeling dizzy after only 1/2 cup of wine. I don't feel the benefit of drowsiness outweighs the hangover symptoms, so I do not think I will be taking this any more.