It helps a lot with the withdrawals. And is helpful if you immedietly start tapering off the phenibut, like start with a 2g dose - then adjust it up accordingly if need be the next day or two, and then immedietly start dropping the phenibut dose by .2 to .5g every day. It itself will cause awful withdrawals if used in high doses for more than two weeks.
But make sure to wait at least 5 hours after your first dose before you adjust your dose up. My first time I took 1.5, waited two hours, then took 2g more, then waited another two hours, then took a whopping 4g more. I awoke on my couch five hours later as my roommate got home from the graveyard shift. I was very high in a bad way and wretched my guts out several times after that. Felt nauseous for two days afterwards.