In the class of nootropic substances, Phenibut occupies a unique space that separates it from many of the other supplements available like Piracetam, Noopept or Aniracetam.
Most Nootropics work by increasing mental energy in an effort to boost concentration and memory.
These are certainly desirable effects for most of the population, but sometimes this can leave you feeling jittery or like your mind is wide awake when you need to fall asleep.
Phenibut works in the exact opposite way, improving cognition but also reducing levels of stress and anxious thoughts. Phenibut reviews often include reports of increased feelings of calm, well-being, and inner peace while using this Nootropic.
The supplement itself was originally developed in Russia and it is a derivative of the powerful neurotransmitter GABA. It is this brain chemical that is primarily responsible for most of the anxiolytic and sleep promoting benefits of the supplement.



- Powerful anxiolytic for stress reduction
- Stimulates GABA receptors & supports sleep
- Neuroprotective & supports cognitive function
How Phenibut Works
Related Topics
- What is Phenibut?
- User Review
- Benefits and Uses
- Dosage Recommendations
- Effects & Mechanisms of Action
- Experience Reports
- Anti-Anxiety Effects
- Using Phenibut for Sleep
- How to Take
- Negative Side Effects
- Withdrawal Dangers
- Risks with Alcohol Combination
- Comparison to Picamilon
- Buying Phenibut Guide
- Using Bulk Powder
- Primaforce Phenibut Review
- SNS Phenibut XT Review
The chemical structure of Phenibut is essentially a modified version of the neurotransmitter GABA with a phenyl group molecule added.
By making this small change, the resulting supplement can pass through the blood-brain barrier much more easily than if you were to take GABA supplements directly.
In fact, using GABA on its own is largely ineffective because in its natural form this neurotransmitter cannot cross the blood-brain barrier to any great degree. GABA has to be synthesized in the brain in order to be used there.
Phenibut avoids this need by giving you the same effects in a compound that has very good bioavailability and excellent transportation across the blood-brain barrier. Once it reaches the central nervous system, it binds to GABA receptor sites which causes increased stimulation of your GABA responsive neurons.
The reason why GABA is so important, especially for those suffering from anxiety and too much stress, is that this is considered to be the chief inhibitory neurotransmitter within the human body. This is the chemical which is largely responsible for turning the brain “off” when it gets too excited or aroused.
From a chemical standpoint, when the brain is excited, too many neurons are firing at once. In cases of too much stress, the neurons seem almost incapable of relenting. GABA comes to the rescue and is able to calm this overactivity, resulting in less over-stimulation and reducing symptoms of anxiety and stress.

- Powerful anxiolytic for stress reduction
- Improves sleep and may reduce insomnia
- Neuroprotective and cardioprotective effects
Phenibut Reviews from Users
Phenibut has a number of devoted users who attest to this supplement’s effectiveness for depression, social anxiety, nervousness, reducing social inhibitions, and generally enabling you to relax and enjoy yourself more.
Some of the most in depth user reviews on Phenibut are found on reddit.com, specifically on the Phenibut subreddit and the Nootropics subreddit. Reading about user experiences here can be a good place to start your research on using Phenibut.
Some people use Phenibut late in the evening to help them have more restful sleep or even to promote lucid dreaming. Other individuals have been known to take Phenibut as a recreational substance in the place of alcohol since some of the effects of these compounds have some similarities.
There are also a number of Nootropic-like effects and benefits to this supplement. This includes helping to improve memory, learning, attention span, focus, concentration, and even decision-making processes. Even those with memory problems or cognition difficulties have said that Phenibut can have positive effects for them.
Beyond the uses of Phenibut as a dietary supplement, it is also administered in medical contexts as a treatment for a number of different conditions. In Russia and certain other European countries, Phenibut is often prescribed for sleep disorders or cases of anxiety.
Phenibut is considered safe when you follow the directions for how to take it properly. The technical term is that it is well-tolerated for human use and consumption. Interestingly enough, the supplement has been included in the standard health kit of Russian Cosmonauts since the early 1970’s.
Research on Phenibut is somewhat limited, and most of the research is dated from when Phenibut was first developed in the the 1960s. More current research needs to be done to fully determine the effects and safety of Phenibut. Even though Phenibut has been used as a prescription medication in Russia for many years, at this time in the USA, the FDA has not approved Phenibut as a drug to prevent or treat any conditions.
Most drugs have a background “I’m high” feeling, which reminds you that changes in your perception are your own brain. A low phenibut dose will seem to change the outside world itself, making it a friendlier and more relaxed place to exist in.
I can’t count the number of times I’ve taken phenibut on a cloudy, rainy, stressful day at work – and then I find myself walking outside on a lunch break in a beautiful sunshine that feels like the universe granted me a gift of a perfect day. Intellectually I know that this is a change in my own perception, but it feels like an external change.” – bibbletribble [5]
I highly recommend to not go above the 2x/week usage guideline. Some guys claim they can take 3-4x/week, but I think its best to play it on the safe side.
As for dependence, if you abuse phenibut by taking it too frequently or continual large doses, you will start to become dependent on it. Phenibut can be a very useful tool in your life to excel you over common obstacles like anxiety & fear. Tolerance from phenibut increases rapidly-I find it works great by taking it Saturday + Sunday, which it then gives me 5 days for my receptors to “reset”.” – dontlistentome5 [1]
I also question the claim that it has any effect on cognition. Other than that, phenibut can be very nice but like any nootropics/research chemicals, you should be very cautious.” – azertii [1]
I don’t know really. I guess I could increase the dose a little bit but I don’t want to harm my body so I’m probably not going to start dosing near 10 grams.I’m a pretty big guy. About 6 foot 4 and 215 pounds. Maybe that has something to do with it?” – [1]
I took 1.25g of phenibut at 12pm because we were leaving at 2:30 pm, I ate absolutely nothing that day to make sure it kicked in by the time I got there but did have a coffee on the car ride there since I heard that was supposed to help a lot.
The effects were super apparent to me. I’ve heard that with phenibut, unless if you have anxiety, you probably won’t even notice effects, but with me they were like light and day. I could talk to everyone easily, had confidence with what I was saying, didn’t have to think a lot about what I was going to say before saying it, it was great.
The real good effects came on the ride home, though. It was just me and my Dad in the car, and we don’t usually talk a whole lot about much of anything, but the whole ride back home I was yapping away talking about shit I would usually never talk about. I even felt a slight euphoria on the car ride home and a little bit after getting home, I was just in an overall good mood.
Also, I sleep like a baby on Phenibut, which is really nice because I had problems sleeping beforehand as well. All in all, phenibut is great. The only problem for me is the onset period because if plans come up on short notice the phenibut probably won’t kick in in time. I won’t be taking phenibut regularly to deal with day to day anxiety, but I will just use it on the days I really need it, that way I can avoid the nasty withdrawals I’ve been hearing about. I’ve never been addicted to anything in my life, and I don’t want to start now. Just thought I should share my experience. Cheers!” – Retzayy [3]
Unfortunately, I seem to have developed a permanent tolerance to most of the effects after using just 100g. I ordered another 100g tub a few years later, and all I feel is slight anxiety decrease and drowsiness, and no euphoria whatsoever. Although one time recently I felt a euphoric rush for about an hour after it kicked in, but it might have been all in my head.” – xYaldabaoth [4]
It makes me extremely lazy and tired feeling also. And every time I take it, I sleep like a rock and can barely wake up the next day. I even feel slight effects the next day. My usual dose has been 1.5g, anything less than 1g I don’t really notice. Overall I would say its OK, I’d give it like a 4/10, nothing special.
I also recently started testing out f-Phenibut. It has a lower dosage than Phenibut and lasts shorter.” – chiefcrunch [6]
However, this time I tried 500mg a bit earlier to see if I could feel it before sleep. And holy cow it was just pure stimulating “push” with a side of anti-anxiety. Like the best parts of adderall without the tweakiness. I could see this being very effective for intense social situations because it’s so motivating as well. This may be the ticket for times when I have to work a room or an institution.” – poisonousautumn [8]
How To Use Phenibut
Phenibut comes in both powder and capsule formulations. Although it is really a personal choice, the powder will be absorbed more quickly and enter into the system easier.
This can come into play if you are using the supplement before bed to help you sleep better. Typically, it can take an hour or two for the supplement to begin working so anything you can do to cut down the lag time is worth it.
It should also be remembered that in a number of cases, it might also take Phenibut a while to build up within your bloodstream and system to really begin feeling the effects. Sometimes this can be a week or two before the benefits are noticeable.
The effects of Phenibut, once felt, can potentially last up to 24 hours although this will be dependent upon a number of difficult to predict factors. There are even Phenibut user reviews that say that this supplement has allowed them to experience more intense and pleasurable orgasms in addition to a feeling of whole-body calm and relaxation.

- Most effective supplements to improve mood
- Optimize levels of dopamine, serotonin and GABA
- Protect against stress and anxiety
Potential Phenibut Side Effects
When sticking to the recommended dosage levels there are no known serious side effects of Phenibut. In fact, it is considered to be one of the safest Nootropics around. Of course, many people also use this supplement as a way to balance out other stimulants.
Doing so could possibly lead to unusual drug interactions although nothing has really been reported in the existing literature. It is generally not a good idea to mix Phenibut with other GABAergic compounds and you should speak to a doctor before you begin using it.
Phenibut Dosage
Proper dosage of Phenibut depends on many different factors including age and personal sensitivities. The below dosage recommendations are a general guideline only, and speaking with your doctor before you begin usage is recommended.
The average daily dosage is normally between 200 and 500 mg, with some users on Phenibut reviews saying they take up to 1000 mg per day. Dosages can be staggered into multiple administrations throughout the day depending on the purpose.
Many users like to use smaller amounts early in an effort to reduce any anxiety and/or jitters caused by stimulants like caffeine and then higher doses later in the day or even to combat sleeplessness. You might not want to take too much in the morning or it may lead to drowsiness or fatigue.
As always, it best to begin with lower doses and only increase once you are more keenly aware of how the supplement is affecting you.
Many people may interested in using Phenibut for anxiety. Before beginning use though it is important to do your research by reading many different Phenibut reviews as well as speaking with your doctor to determine if this supplement is right for your needs.
- Beginner's Guide to Phenibut. Reddit.
- Phenibut Serious Adverse Events List. Reddit.
- Phenibut is amazing. Reddit.
- I honestly think phenibut is my favourite overall drug.. and it's legal. Reddit.
- The beauty of a low dose. Reddit.
- Phenibut is the most amazing drug ever. Reddit.
- Phenibut first time, Holy Shit. Reddit.
- 500mg sweet spot?? Holy cow. Reddit.
- Volkov AE, Kuzam LN, Borsheva AA. [Effect of fenibut on the fetus and newborn infant after the treatment of gestoses]. Akush Ginekol (Mosk). 1989
- Zyablitseva EA, Kositsyn NS, Shul'gina GI. The effects of agonists of ionotropic GABA(A) and metabotropic GABA(B) receptors on learning. Span J Psychol. 2009
- Högberg L, Szabó I, Ruusa J. [Phenibut yielded withdrawal symptoms and psychosis. Drugs for cosmonauts--now marketed as dietary supplements online]. Lakartidningen. 2013
- Ziablitseva EA, Pavlova IV. [Effect of GABA receptor agonist phenibut on behavior and respiration of rabbits in the negative emotional situation]. Zh Vyssh Nerv Deiat Im I P Pavlova. 2007
- Ziablintseva EA. [The effect of GABA derivative phenibut on defensive conditioning and internal inhibition]. Zh Vyssh Nerv Deiat Im I P Pavlova. 2006
Article last updated on: March 13th, 2018 by Nootriment
2 Comments
Great compound when used sensibly – and taken once or twice a week max
i use phenibut for more than a year now at a dosage of 500mg every 24 hours.
It has the same powerfull effect on me all the time.
I dont have any desire to use more!
However ..a few days in a month, it feels like it doesnt work that good.
Then i keep my discpline and never use more then 500mg.
When i dont use it i go back to my old self: nervous not focussed , socialfears and so,
So…. for me its a life-enhancer,
Its a pitty it is not accepted by psychiatrists and doctors as an official medicin.