Phenibut: The Nighttime Nootropic


Phenibut is a derivative of GABA that exerts extremely powerful relaxation, sleep, and nootropic benefits.

Phenibut has become increasingly popular in recent years for its ability to combat stress, enhance mood, and even boost brain function. You can find it in all manner of sleep aids and nootropic formulas, but what exactly is this ingredient, and is it something you should make a staple in your daily supplement regimen?

We answer all that and more as we dive down the phenibut rabbit hole.

But as a word of warning up front, this compound is not for anyone who has an addictive potential. It must be taken seriously and dosed responsibly, or not dosed at all.

Phenibut was invented in Soviet Russia, and has been used to treat anxiety, sleeplessness, alcoholism, and other issues.

  • The primary benefit is its anxiolytic effect (anti-anxiety), which has allowed some to sleep better. (See the phenibut benefits section)
  • Doses begin at 250-500mg per day, and it should never be used more than two days in a row to prevent addiction and tolerance build-up. (See the phenibut dosage section)
  • The main unwanted side effects are addiction and withdrawal (hence the dosing guidelines above). Too high of a dose may cause fatigue, anxiety, vomiting, and hallucinations. (see the phenibut side effects section)

  • Featured phenibut products:

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What is Phenibut?

Phenibut is the brainchild of 1960s Soviet scientists who were trying to develop superior soldiers and cosmonauts in their quest to defeat their Cold War nemesis, the United States. Despite their calamitous defeat in that particular endeavor, the years of research led to the creation of several synthetic nootropic compounds, including phenibut.[1]

Phenibut GABA Comparison

Notice the similarities in structure between Phenibut and GABA?

Phenibut is a synthetic analog of the neurotransmitter GABA, one of the primary inhibitory neurotransmitters in the brain. It’s structurally similar to GABA and possesses the ability to cross the blood-brain barrier (due to the addition of the phenyl ring by the Russian scientists), something GABA cannot do easily.[2] GABA is naturally synthesized in the brain itself, which means it normally doesn’t need to cross the blood-brain barrier to take effect.[3]

Phenibut has been used to treat a number of various ailments include post-traumatic stress disorder (PTSD), anxiety, insomnia, depression, asthenia, alcoholism, stuttering, and vestibular disorders, among others.[2] You can also find Phenibut listed under several other names including:


Easy there, kids… phenibut is a prescription-strength pharmaceutical tranquilizer… it works, but it’s addictive!

  • β-Phenyl-γ-aminobutyric acid
  • Noofen
  • Fenibut
  • Phenybut
  • Citrocard

How Does It Work?

Since phenibut is a synthetic derivative of GABA, and has a slightly different chemical structure than GABA, it interacts with other neurochemicals a big differently than pure GABA does. Basically, phenibut operates as an agonist of GABA receptors within the brain.[4] It acts as a GABA-mimetic primarily on the GABA-B receptors[24] (with minimal action on the GABA-A receptors), but also has been shown to stimulate the dopamine receptors as well as antagonize beta-phenylethylamine (PEA), “a putative endogenous anxiogenic” (substance that causes anxiety).[1] In other words, phenibut modulates neuronal excitability, which prevents the brain from becoming hyperactive.

Phenibut’s effects in the body are incredibly long-lasting, even though its plasma half-life is only 5.3 hours.[1] This is due to Phenibut’s actions on your GABA receptors, which will last long after your kidneys have removed all of the phenibut from your system.[5,6]

Benefits of Phenibut

Phenibut is best known as an anxiolytic, but that just begins to scratch the surface of this potent and unique compound’s benefits:

  • Anti-Anxiety

    Phenibut Lavin Table 1

    Here’s a full list of the effects Phenibut has to offer as found in the research.

    Phenibut is most frequently used for its strong anxiolytic effects.[1] Research has shown that the smart drug has a pronounced effect on reducing stress and feelings of anxiety. This has also led to many using it to improve their sleep quality, as stress is oftentimes one of the biggest reasons for poor sleep.[7,8]

  • Enhanced Mood

    In line with phenibut’s stress-relieving qualities, a number of folks actually use it for enhancing mood. Much of the mood-improving effects of phenibut can be attributed to its ability to increase dopamine in various regions of the brain, including the striatum.[1] This also means phenibut can help reduce irritability, tension, and fatigue accumulated throughout a stressful workday.

    Phenibut may also help mellow you out if you’re one of those guys who flies off the handle easily, as a study conducted in rats showed the compound decreased aggression when provoked.[10]

  • Enhanced Cognitive Function

    Phenibut Aggression

    Phenibut is also an effective analgesic and anti-aggression supplement as well.[10]

    Phenibut may promote higher cognitive function by improving attention, motivation, concentration, and learning. In a study conducted in rabbits, phenibut was shown to enhance the subjects’ brain responses to a conditioned stimulus [11,12,13]

  • Neuroprotective

    Brain ischemia occurs when blood supply to the brain is compromised, which leads to poor oxygen supply (cerebral hypoxia), potentially resulting in stroke or death of cerebral tissue. Ischemia can lead to changes in brain metabolism and reductions in metabolic rates, which can significantly impact body movement, vision, and speech.[14] Moreover, cerebral ischemia has also been implicated in degenerative neurological disorders including Alzheimer’s.[15]  

    Phenibut has been shown in animal trials to exert neuroprotective effects by protecting neuronal cells against ischemia, edema, stress, and trauma.[1,16,17]

  • Cardioprotective

    Phenibut has also been found to exert cardioprotective effects, specifically in regards to the muscular tissue of the heart, a.k.a. the myocardium. Studies conducted in vitro and in vivo in rats with chronic renal insufficiency found that phenibut decreased the myocardial hyperfunction and reduced contractility to control levels, as well as accelerated relaxation in all finite systolic lengths.[18,19]

  • Anti-hypoxic

    It also acts as an anti-hypoxic.[1] During periods of extreme training, working muscles can’t get sufficient oxygen at a certain point become hypoxic, which inhibits the muscle’s ability to contract. Preventing hypoxia, allows the muscle to withstand more stress for greater amounts of time, and this increased metabolic stress helps bring about hypertrophy. Additionally, phenibut can also increase one’s tolerance to metabolic stress, which allows for more intense training sessions, yielding better gains.[20]

  • Increases Growth Hormone

    Phenibut Learning

    Phenibut exerts anti-amnesiac properties as well as nootropic benefits in rats.[13]

    GABA has been shown to increase growth hormone levels between 175-375% in athletes. [21,22] Due to structural similarity between GABA and phenibut (as well as their similar effects), it’s often extrapolated that gym goers can stand to benefit from supplementing with phenibut to help them increase growth hormone secretion. However, no actual studies have been performed with athletes supplementing with phenibut prior to training, so we feel this perceived benefit might be a bit of a stretch.

  • Stimulatory behavior?

    What? If phenibut is known to reduce anxiety and promote sedation, how can it be stimulating as well?

    It all has to do with the dosing. In low amounts, PEA actually functions as a sedative rather than an anxiogenic. Phenibut has been shown to be an effective antagonist of PEA, which means that phenibut can counteract those sedative qualities of PEA (when it’s taken in low doses), indirectly making it a stimulant.[1]

    Again, the key here is a low dose of phenibut – animal studies found that PEA acted as a sedative when dosed at 5 to 10 mg/kg in mice. Those researchers used a dose of 100mg/kg phenibut to counteract the effects of PEA.[9]

    Note that these doses are astronomical in terms of humans and should never be tested – we urge you not to use this combination of ingredients.

Phenibut Dosage

Dosages for phenibut are all over the place depending on what you’re using it for. But given the risk associated with phenibut for rapid tolerance build up and withdrawal symptoms, we suggest starting at 250 – 500mg per day, used no more than two days in a row, and you can assess how you react.

Some research studies have dosed phenibut as high as 1,500mg 2x / day, but that’s far too massive of a dose to start with, and we highly suggest beginning at the bottom range of phenibut dosing. You’re less likely to build a tolerance rapidly and develop withdrawal symptoms.

Consuming 3 grams / day has been consistently shown to result in tolerance build up to Phenibut and inevitable withdrawal when abstaining from the drug (consistently results in a strong tolerance to Phenibut’s effects and withdrawal when no longer taking the drug.[1,23]

Additionally, phenibut addiction can develop in under 10 days,[5,23] which is why we strongly recommend NOT consuming it every day of the week.

Side Effects of Phenibut?

Anxious Girl

While phenibut is an anti-anxiety drug, too much of it actually can make you anxious.

Compared to some of the other nootropics we’ve covered on the PricePlow blog, phenibut’s are definitely more pronounced, particularly when it comes to phenibut withdrawal. Symptoms commonly associated with phenibut (especially during withdrawal) include:

  • Addiction
  • Fatigue
  • Anxiety
  • Loss of appetite
  • Nervousness
  • Vomiting
  • Possible hallucinations.

Side effects experienced while supplementing with phenibut include headaches, dizziness, lethargy, “hangover effects.”

Don’t get hooked! Use strategically and responsibly

Phenibut Addiction

This dude got so f’d up on phenibut that he had to go to an addiction clinic where they had to substitute baclofen while weening him off of the phenibut, and then ween him off of the baclofen.[24] This stuff is no joke, so be cautious and stay aware1!

It’s extremely important to respect this compound with regards to its addictive potential – especially if you are prone to addictive tendencies.

In one case study, a former alcoholic became so hooked on phenibut and kratom that he required 12 weeks of medical support and anti-addiction pharmaceuticals to ween off of the addiction, and withdrawal symptoms were bad.[24] Other similar cases have been reported,[25] so this is not an uncommon occurrence.

This is why we’re staunch on lower doses, and repeatedly suggest that you never use phenibut more than two nights in a row. That third night must be an off-night.

Best Supplements Containing Phenibut

  • Single-Ingredient Supplements:

    • SNS Phenibut XT (both pills and powder)

      SNS is our go-to for single-ingredient products such as this. They provide both pills and powder below:

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      SNS Phenibut XT Ingredients

      Phenibut XT’s capsule version contains 500mg per cap, but a powder is also available.

  • Sleep Aid Powders:

    • Hi-Tech Pharmaceuticals Somatomax

      The most popular, and possibly the most powerful one, with a serious dose of phenibut (somewhere between 2-3g).

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      Hi-Tech Somatomax Ingredients

      Somatomax contains a whopping 2-3g of Phenibut per serving, so start off on the lower side with 1/ 2 scoop!

    • RedCon1 Fade Out

      A non-proprietary blend that has 1g phenibut, but also mixes in some herbal ingredients such as mucuna pruriens and valerian for a two-hit combo.

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      RedCon1 Fade Out Ingredients

      RedCon1’s Fade Out goes both herbal and synthetic for a best-of-both-worlds – and it’s an open formula!

Stacking Phenibut

Phenibut is an incredibly powerful nootropic / sleep aid in its own right, so we strongly recommend getting a hold on how you react to it on its own before going off and trying one of these stacks:

  • Noopept + Phenibut


    Noopept is one of the most potent nootropics you can use, just make sure to pair it with a source of choline to avoid brain fog if you’re stacking it with Phenibut/

    This stack extremely potent, and great for enhancing sociability and focus. On its own noopept is pretty strong stuff, but when combined with phenibut, the two combine to create a highly effective stack that boosts mood, alertness, and create a sense of euphoria.

  • Phosphatidylserine (PS) + Bacopa Monnieri + Phenibut

    Phenibut on its own not doing enough to relieve your stress and anxiety? Then give this mega stack a try!

    The trifecta of mood elevators dramatically reduces anxiety and apprehension. It can also be useful for improving mood or combating sleeplessness.

  • L-Theanine + Phenibut

    Here’s another option for alleviating anxiety and stress. These two ingredients significantly increase your ability to “chill out”, just be careful of going to heavy on the dosing for either one, as you’ll feel half-baked.


Phenibut is certainly an effective ingredient for eliminating stress, improving mood, and getting one amazing night’s sleep, but it’s definitely not for everyone (especially if you have an addictive personality). It’s incredibly easy to build a tolerance, and should be used very infrequently.

All that being said, it does offer some promise as a worthwhile nootropic, but like most other smart drugs, it’s going to take a bit of personal experimentation to find out if it’s for you or not.

Just be careful with this stuff, keep the doses low, and stop use if you find yourself getting hooked or wanting it more than two nights in a row, especially if you have an addictive personality.

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All blog posts mentioning Phenibut:

About the Author: Mike Roberto

Mike Roberto

Mike Roberto is a research scientist and water sports athlete who founded PricePlow. He is an n=1 diet experimenter with extensive experience in supplementation and dietary modification, whose personal expertise stems from several experiments done on himself while sharing lab tests.

Mike's goal is to bridge the gap between nutritional research scientists and non-academics who seek to better their health in a system that has catastrophically failed the public.

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