Phenibut is a GABA agonist, which creates a sedative effect. You can use phenibut for sleep in a similar dosage as recommended: 250 – 500 mg per day
According to a 1986 study in the Pavlovian Journal of Biological Sciences, phenibut can significantly improve sleep quality . While these studies have not been confirmed in western literature over many studies, it is indicative of the usefulness as a sleep aid.
Why Phenibut Enhances Sleep
Phenibut primarily interacts with brain circuitry that is related to relaxation and calmness. In particular, the GABA and glutamate receptors heavily influence our ability to get restful sleep and relax in general. One of the reasons alcohol is so popular is because it interacts with the GABA receptors to help people feel more relaxed while having a glass of wine, enjoying a beer, or a stiff shot of whiskey.
Obviously different chemical substances interact with the brain in different ways. Even though both phenibut and alcohol interact with GABA receptors does not mean they're much alike. Phenibut will not create a lack of balance or reduce inhibitions in most cases, but it will help to calm your nerves and allow you to enjoy more restful sleep.
Dosing Phenibut and Risks
As with any nootropic, there are risks associated with using phenibut for sleep. Phenibut is prone to tolerance and many recommendations suggest using the drug no more than 1 – 2 times per week. Someone who uses phenibut daily for sleep will create a tolerance over a short period.
Tolerance to phenibut results in higher usage and greater doses. Anyone who is using phenibut more than 1 – 2 per week will probably find their needs increasing to maintain the mood and feeling of euphoria.
Some people find that phenibut is too sedative after a certain dosage. By taking the drug, they hope to feel less anxiety while being social and they end up falling asleep rather than going out at all .
Aside from the risk of tolerance, there are withdrawal effects that can be debilitating for some people. There are complaints of headaches, nausea, upset stomach, and a variety of others that cause symptoms similar to a hangover. Many people find this unpleasant and seek more phenibut to make the sensations go away. In the long-run, this is a poor strategy, however.
Even though there are some people who have had poor experiences with phenibut, withdrawal, and tolerance in the past, that doesn't mean everyone is prone to these results. If you utilize phenibut with care and in a short-term fashion, it will probably make a positive change in your life. For certain people, perhaps yourself among them, getting a restful night of sleep is important, but not always easy. Enter phenibut.
Benefits of Phenibut for Sleep
Despite the tolerance and withdrawal side effects, using this drug correctly can have significant benefits. One Redditor commented that phenibut “…gives me the happiest, sleep ever. I can’t recreate it with anything else in any combo I’ve tried.” 
While this may be a unique experience to him, it is worth looking at if you have poor sleep. Make sure to find a reputable vendor such as Nootropics Depot before you buy phenibut. Click here to buy from a vendor we have vetted.
Editors' Thoughts on Phenibut
Since I've been involved with nootropics, I have never had a problem sleeping. Within 5 – 10 minutes, before I know it, I'm lights out. For that reason, I've never taken phenibut for sleep myself though I know many people who have. Tolerance and withdrawal problems do occur, but I don't know anyone who has experience with it. In fact, in a recent visit to my friend Luke Storey, he reminded me how he was addicted to heroin and countless other substances, but doesn't have any issues with phenibut.
Either way, if you are skeptical about the potency of phenibut and don't want to go down that rabbit hole, I might suggest lemon balm. It's a GABA transaminase inhibitor (so GABA doesn't break down), which increases relaxation and sleep as well.
Mansal Denton, Nootropedia Editor