Everything You Need To Know About Phenibut

phenibut slowing down brain waves

Stress and anxiety can have a downright paralyzing effect on our lives.

That’s why so many people turn to anti-anxiety drugs and supplements to help them get by.  One substance that sort of bridges the gap between anti-anxiety drug and anti-anxiety supplement is Phenibut.

It’s a synthetic derivative of the amino acid GABA which was originally developed to treat anxiety and insomnia several decades ago.

However, due to the development of better drugs–like Alprazolam and Temazepam–for treating those conditions, Phenibut never became an approved drug in the US.

Instead, it has made it’s way into all kinds of supplements, from stress formulas to sleep-aids.

It’s cheap.  It’s easy to obtain.  And it works.

But there are some downsides…

This begs the question: is Phenibut really worth it?

In this article, we’ll cover everything you need to know about Phenibut, including:

  • What It Is
  • How It Works
  • Dosage
  • Side Effects
  • The Phenibut High
  • Tolerance/Addiction
  • Natural Alternatives

By the end of it, you’ll know all the facts.  Once you know the facts, you can decide for yourself whether Phenibut is worth a shot.

What Is Phenibut?

Phenibut, or β-Phenyl-γ-aminobutyric acid (if you want to be scientific about it), is a central nervous system depressant which was originally developed by Russian scientists in the 1960’s.

Chemically, it is GABA, but with the addition of a phenyl ring.

phenibut chemical molecule

This alteration in chemical structure allows Phenibut to easily bypass the blood-brain-barrier and enter the brain, where it causes a variety of psychoactive changes, including:

  • less anxiety
  • freeing of inhibitions
  • relaxation/drowsiness

Phenibut is also believed to have some nootropic benefits, but not much research has been conducted in that area.

It’s much more reliable as anti-anxiety supplement.

Why Do People Supplement With Phenibut?

Phenibut is usually used for one of the following reasons.

It’s typically of interest to people who want to use something that’s more powerful than most anxiety-reducing supplements but not as hardcore as most anti-anxiety drugs.

You can think of Phenibut as the middle ground between drugs and supplements.

Not quite as effective for reducing anxiety as most anti-anxiety drugs, but more powerful than any natural supplement.

How Does Phenibut Work?

Phenibut belongs to the same class of chemicals as Gabapentin, known as gabapentinoids.  However, unlike Gabapentin, Phenibut has a direct effect on GABA receptors.

GABA is the chief inhibitory neurotransmitter in the brain.  It’s job is to down-regulate the firing of neurons which slows overall brain activity.

As a GABA-receptor agonist, Phenibut increases GABA activity in the brain, effectively slowing down brain activity.

You see, on a fundamental level, anxiety is the result of an over-active brain.  Since GABA’s job is to reduce brain activity, it is often targeted for the purposes of reducing anxiety.

Drugs like Alprazolam and Etizolam target the GABA receptors, but only at specific sites, called benzodiazepine receptors.

Phenibut, on the other hand, is a full-agonist of the GABA receptor.

It also blocks α2δ subunit-containing voltage-dependent calcium channels, the same mechanism underlying the pain-reducing effects of Gabapentin.

Whether or not Phenibut could potentially help with chronic pain like Gabapentin remains unclear, but the sedative and anti-anxiety effects are well established.

Phenibut Dosage

When we’re talking about supplements, the term ‘clinical dose’ simply refers to the amount of a given substance shown in scientific studies to exert whatever effects.

Due to the lack of human studies on Phenibut, however, there really isn’t a precise clinical dose.

Recreational use and anecdotal reports have carved out an effective range though.

Normal doses of Phenibut are usually in the 250m-1000mg range, with doses as high as 2 or 3 grams being used in some cases as well.

Obviously the higher the dose, the higher the likelihood of developing side effects, so starting low (250-500mg) is strongly recommended.

Phenibut Side Effects

Phenibut does have the potential to cause some side effects.

Some of the less severe, mildly unpleasant side effects include:

  • Nausea
  • Dry Mouth
  • Increased Appetite
  • Headache
  • Grogginess
  • Sweating

Rare, more severe side effects include:

  • Loss of motor control
  • Respiratory depression
  • Digestive Tract bleeding
  • Withdrawal (when you stop)

By itself, Phenibut is not particularly toxic.  You would have to take A LOT to over-dose.

There are no reported instances of death from Phenibut alone, but combined with alcohol, opiates, or benzos, it can potentially be lethal.

As with any drug or supplement, the user experience is highly variable.  While you may not experience any side effects, your friend who took the same dose could experience all of them!

It depends on too many factors to be predictable.

Does Phenibut Get You High?

Phenibut is definitely psychoactive, so in a sense, you could experience a high from it.

The Phenibut high is somewhere in the neighborhood of benzodiazepines and alcohol, but not as powerful.

  • Lower Inhibitions
  • Not Caring About Stuff
  • Sedative-Like Effects

It’s not the type of high that many people chase, but depending on your brain chemistry, Phenibut might feel pretty good.

Obviously the more you take, the more likely it is that you’ll experience these sorts of effects, but even at normal doses the psychoactive effects can be felt.

In my personal opinion, Phenibut sucks.

I would never use it to get high because, quite frankly, it just doesn’t provide much of what I would call a “high”.

For me, it’s more like a sluggish, depressing, cloudy-headed state that lasts several hours and leaves me feeling mildly uncomfortable and a little hungry.

I’ve experimented with doses of 500mg to 3000mg (3 grams), and I can honestly say that the “high” feels like a less effective, less precise version of Alprazolam (Xanax) or Etizolam.

And this isn’t one of those situations where the supplement is safer than the drug.  Phenibut, like any benzodiazepine (anti-anxiety drugs), carries some risk of addiction.

My Personal Experience With Phenibut

I’ve experimented with Phenibut at different dosages on and off for several years.  To be honest, I’m not a huge fan.

For me, there is no ‘Phenibut high’. At least, not one that’s enjoyable.

High doses of Phenibut just make me sleepy and sort of relaxed, but also just kind of dizzy and uncomfortable.  The effects are nothing compared to drugs like Etizolam or Clonazolam and the side effects are more apparent.

Phenibut withdrawal is no fun either…

The longest I’ve ever taken it without taking a break is 2 or 3 weeks.  For several nights after I stopped, I couldn’t sleep and felt generally anxious through the day.

I wouldn’t say it’s anywhere near as severe as benzo-withdrawal, but it’s withdrawal nonetheless.

Considering the lack of positive effects, I really just don’t see how the negatives (dependence/withdrawal) are worth it.

Obviously, everyone’s experience is going to be different.  You may very well derive some benefit from Phenibut and it’s entirely possible that I’m biased due to the fact that I’m not stranger to much stronger anti-anxiety drugs of the benzodiazepine class.

There’s certainly no harm in giving Phenibut a chance, but I think it’s a bit over-hyped.

Is Phenibut Legal?

Phenibut is one of many substances which occupies a bit of a legal gray area in the US.  Contrary to popular belief, it’s actually not legal to sell Phenibut as a dietary supplement.

Technically, it’s an unapproved drug, but since it’s also unscheduled (uncontrolled), it’s legal to buy, sell, and possess.

In other words, you can sell it.  You just can’t call it a dietary supplement.

For that reason, you won’t find it at major supplement retailers like Amazon or GNC.

It is readily available from plenty of internet retailers, though.

As always, the important thing is that, as a consumer, you’re not going to get in any trouble for buying Phenibut.  If anything, it’s the companies that sell it who need to be a little careful with their marketing and the types of claims they make.

Where To Buy Phenibut

Like I said, you can’t buy Phenibut from any major supplement retailers, but it’s not hard to find.

You can buy Phenibut from these vendors:

Obviously, there are a tons of vendors who offer Phenibut, but not all of them are trustworthy.

If you don’t see a Certificate of Analysis (COA), I wouldn’t trust it.  Unfortunately, most nootropics vendors don’t bother to test each batch and you’re rolling the dice a little by going with that sort of vendor.

Is Phenibut Addictive?

man suffering from phenibut addiction

Phenibut users can become somewhat dependent on Phenibut.  It is known to cause withdrawal symptoms in those who use it regularly and then suddenly stop.

Withdrawal symptoms are typically similar to those of benzodiazepines, but less severe.

  • Trouble sleeping
  • Restlessness
  • Anxiety
  • Loss Of Appetite
  • Inability To Concentrate

These are all things that can happen if you take too much Phenibut and then suddenly stop taking it.  There’s no evidence that Phenibut withdrawal can kill you–as is the case with benzodiazepine withdrawal–but it’s definitely unpleasant.

So, do yourself a favor…

Don’t take Phenibut every night.  That’s the single most common way people become addicted to it.

If anything, keep some on reserve for special occasions where you really can’t sleep.

It’s really not an every day thing.

Natural Alternatives To Phenibut That Aren’t Addictive

If you’d rather not risk becoming dependent on Phenibut, there are some 100% natural supplements that can potentially do things like reduce anxiety and help you sleep better.

Let’s go over a couple of the very best.


Ashwagandha is an Ayurvedic herb which has been shown clinically to reduce stress and help manage anxiety.

There is also research showing that it can improve physical performance, enhance recovery, and encourage healthy Testosterone levels, but those effects are just an added plus.

If you’re looking for an all-natural stress-reliever that has actually been proven to work in human beings, Ashwagandha is worth considering.

The clinically effective range is anywhere from 300-600mg daily, depending on the extract.

I’d recommend using KSM-66®.  It’s a patented form of Ashwagandha that is guaranteed to be standardized for a certain amount of the active components.


Phosphatidylserine is a naturally occurring phospholipid which plays a vital role in the structural health of cell membranes.

Interestingly, Phosphatidylserine has actually been shown to reduce Cortisol (stress hormone) levels as well as perceived mental stress.

How exactly it works remains unclear, but the stress-reducing impact of PS has been observed in numerous studies at this point.

It’s been remarkably well-tolerated throughout all of them too.

The clinical range is anywhere from 200-800mg.


L-Theanine is a unique, non-dietary amino acid found in Green Tea (and Matcha)

It is generally believed to be the reason why Green Tea, despite containing Caffeine, doesn’t cause many of the negative side effects associated with Caffeine (jitters, anxiety, etc.).

Studies have confirmed that Theanine is indeed synergistic with Caffeine in such a way that enhances the positive aspects of Caffeine while eliminating some of the negative side effects.

By itself, Theanine has been shown to reduce anxiety and induce a state of relaxation, mediated in part by an increase in alpha brain waves.

The clinically effective dosage for Theanine varies, but it’s been shown to exert effects between 100 and 400mg/day.

If you’re taking it with Caffeine, try matching the dose (i.e. 200mg of Caffeine and 200mg of Theanine).

The Bottom Line On Phenibut

Phenibut is capable of reducing stress and anxiety, and may have some sort of nootropic benefits associated with it as well.

While there isn’t much in the way of actual human research, it is commonly used for the treatment of anxiety and insomnia.  All the anecdotal and preliminary evidence suggests Phenibut is definitely effective, but the ideal dose may vary widely from person to person.

Unfortunately, as is the case with many drugs which act on GABA receptors, Phenibut use can result in dependence and dependence can result in withdrawal symptoms when stopping.

Withdrawal isn’t THAT severe for most people, but it happens, so using Phenibut on a daily basis is ill-advised.  This is one supplement that should only be used every now and then when you really need it.

What’s Your Take On Phenibut?  Comment Below…

I’m Matt Theis, founder of SuppWithThat, Momentum Nutrition, and Singular Sport. I created SWT to separate the science from the hype and publish accurate, research-based information on supplements. If you like what I have to say here, feel free to check out my supplements at and

Click to comment
To Top