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Phenibut is mainly used as an anti-anxiety and stress reducing supplement, and is very effective at both roles. It can also be used occasionally to reduce insomnia and to improve sleep quality, although it is not recommended to be used more than twice a week for this purpose in order to prevent the formation of tolerance.
To reduce anxiety, a typcial dose of 250 - 500 mg is recommended. While doses up to 1000 mg are safe and effective, we generally recommend not exceeding a dose of 750 mg as side effects are more likely at higher doses and tolerance will form faster.
It is not recommended to use Phenibut more than twice per week as doing so will cause a tolerance to form rapidly.
When taken at doses of 250 - 500 mg, Phenibut is very well tolerated and unlikely to cause adverse side effects. Side effects become more common at higher doses and include sedation, drowsiness, nausea, dizziness, and headaches. When taken at doses exceeding 1000 mg, side effects such as motor incoordination and loss of balance can occur.
Tolerance to Phenibut develops with frequent use, so it is recommended that Phenibut not be used more than twice per week. If a tolerance does develop, withdrawal symptoms including rebound anxiety, insomnia, irritability, and agitation may occur upon discontinuation. Tolerance and withdrawal symptoms can be avoided by not using Phenibut more than twice per week and in doses not exceeding 500 mg.
Phenibut should not be combined with alcohol, benzodiazipines, or other sedatives. It should not be used by children, anyone who is pregnant or breastfeeding, or by anyone suffering from liver or gastrointestinal disease. You should not operative heavy machinery after using Phenibut.
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Phenibut (β-Phenyl-γ-aminobutyric acid) is a compound that was derived in the 1960s by Russian scientists for cosmonauts. (1,3,4) Phenibut was designed to reduce anxiety, stress, tension, and fear while promoting healthy sleep while the cosmonauts were in space. (1,3,4)
Phenibut is an un-scheduled substance in the United States meaning the sale and possession of it does not require any license and prescription. Phenibut is treated similarly in the European Union as it is in the United States, however European countries such as Russia and Ukraine market Phenibut for medicinal use. (1,3) In Australia, Phenibut is a schedule 9 substance, meaning it is illegal to possess, distribute, or manufacture.
Phenibut is most commonly used in the United States as a supplement for its anti-anxiety (anxiolytic) properties. (1,2,3,4,5,6)
The primary role of Phenibut is to act as an inhibitor for GABAʙ to reduce feelings of stress, anxiety, and to promote relaxation. (1,2,3,4,5,6) Phenibut also acts to improve sleep quality. (7,14,15) Phenibut has become popular for athletes and weight lifters due to its impact on Human Growth Hormone (HGH). (9)
Phenibut has other benefits that will be discussed in the “Research and Scientific Studies” section and include but are not limited to:
Phenibut is most commonly found as a powder or in capsule form. It is recommended to take Phenibut as a capsule vs. the powder due to the powder’s poor taste. (4) When found in capsule form, Phenibut most likely is found in the 250mg – 500mg range and is best if taken on an empty stomach as food will slow down the time for Phenibut to take effect. On average, it takes 2 – 4 hours for Phenibut to take effect. (5)
It is very important to cycle Phenibut as you can very quickly build a tolerance. It is not recommended to take Phenibut more than two times per week as your tolerance builds you will need more Phenibut to feel the effects which increases the likelihood of side effects. (4,5)
Phenibut Dosage Guidelines
Phenibut dosages should start small until you understand how it will affect your body. Start with one, 250mg dosage and build up to either two, 250mg or one, 500mg dosage per day. Since Phenibut can take up to 4 hours to kick in, ensure you wait before adding additional doses to avoid building a tolerance.
Half-Life and Duration of Effects
Phenibut takes 2 – 4 hours to take effect so you should not begin to take more if you don’t feel effects immediately. (5) If taking Phenibut at appropriate doses on an appropriate cycle, you can expect the anxiolytic feelings to last from 4 to 10 hours.
When taken at appropriate doses, there are few side effects that have been reported with Phenibut. (4,5) The most commonly reported side effects associated with appropriate doses of Phenibut include; sleepiness, headaches, or mild feelings of depression as the supplement starts to wear off.
When taken at higher doses, side effects become more severe and include; flushing, tingling, anxiety, fatigue, or dizziness.
As tolerance for Phenibut builds quickly and cycling is recommended, it is strongly recommended to not exceed a dose of 500 mg of to use Phenibut more than twice per week. You should not have issues with symptoms of withdrawal if taking less than 500mg of Phenibut nor more than twice per week.
Phenibut should not be mixed with alcohol or other sedatives. Alcohol, like Phenibut, acts to increase GABA activity and to cause sedation. If combined, it increases the risk of an overdoes which could lead to a loss of consciousness or other mental issues. Additionally, like Phenibut, alcohol can be habit forming and trying to overcome addiction to multiple substances makes it harder to overcome more severe withdrawal symptoms. (3,5,13)
There is a compound similar to Phenibut, F-Phenibut, which possesses similar effects. However, F-Phenibut has only recently become available and very little is known about the compound including its potential toxicity. (4) Our Phenibut is not F-Phenibut.
It is possible to overdose on Phenibut, especially when combined with alcohol or other sedatives. We strongly recommend not exceeding a dose of 500 mg per day, though if not combined with other products a dose as high as 2 grams will not cause an overdose.
Phenibut is a synthetic compound derived from GABA. Phenibut works by acting as an agonist (a chemical that binds to the receptor of a cell and then activates the receptor to cause a physiological response) to GABAʙ, and at high dosages, to GABAᴀ. (1,2,4,5,6)
GABAʙ is the major inhibitory neurotransmitter in the brain meaning it inhibits synapses and neuronal processes (most prevalently the signals associated with anxiety). GABAʙ is important for attention, alertness, and concentration. However, when these levels are at an excess, they cause stress, anxiety, and a lack of sleep. So, by Phenibut binding to GABAʙ, it helps to reduce these feelings. (1,5,6)
Phenibut also works by stimulating the neurotransmitter dopamine, its receptors, and antagonizing beta-phenethylamine (PEA). (5,6) PEA acts by increasing the action of dopamine, which aids in memory formation, focus, and cognition.
The effectiveness of Phenibut is drive by the addition of a phenyl group in the β-position, which is what makes it distinctive from GABA. The addition of this phenyl ring is what allows it to cross the blood-brain barrier. (1,5)
Improved Blood Flow to the Brain (8)
A study was conducted on rats that had an inadequate blood supply to the brain caused by a blockage of the carotid arteries. It was found that the introduction of Phenibut lead to numerous benefits for these rats that included; a reduction of neuralgic deficiency, reduced amnesia, improved control for the brain on cerebral blood flow, and improved spontaneous movement.
Improved Sleep Quality (7,14,15)
Several studies have been conducted on sleep quality using Phenibut and other GABA agonists. These studies have varied over individuals with normal sleep cycles and sleep disorders.
One double-blind, placebo-controlled study was conducted measuring sleep latency and during by form of a questionnaire. Sleep quality was measure on a visual analog scale while sleep latency was measured using electrocardiographic readings. Statistically significant differences were found in; time to fall asleep, duration of sleep, ease of falling asleep, awakenings, and grogginess between the control and placebo groups.
Additional studies found that sleep anxiety and sleep disturbances were decreased.
Elevation of Human Growth Hormone (9)
GABA has been found to have an effect on stimulating pituitary glands to produce more Human Growth Hormone (HGH). As HGH is associated with muscle repair and bone density restoration it has become popular in the weight lifting community. By supplementing with Phenibut, you’re able to increase GABA levels.
In one study, levels of GABA lead to a statistically significant increase in levels of HGH.
Cognitive Enhancement (10)
Noofen, a Latvian medicinal form of Phenibut was used on individuals with anxiety-phobic disorders to determine its effectiveness in assisting with cognitive and emotional development.
62 individuals were neurologically examined, given questionnaires to determine anxiety via the Hamilton anxiety rating scale, and tested on memory impairment via methods developed by A.R. Luria. In 73.3% of these cases, improvements were seen demonstrating that Phenibut has the potential to assist in cognitive enhancement.
Helps to Protect the Heart from Stress (11)
Phenibut was used on a test of animal hearts, specifically left ventricular pressure, heart rate, and maximum intensity of functioning. The tests were set-up to determine how the heart would respond to increased levels of stress.
It was determined that the animals who were give Phenibut, had their hearts perform 1.8 times better than the animals who were not.
Is GABA the same as Phenibut?
No, Phenibut is a synthetic compound that acts as an agonist of GABAʙ causing increased GABAʙ levels.
Is Phenibut legal in the United States?
Yes, Phenibut is completely legal to sell and possess in the United States and Europe.
Can I take Phenibut every day?
Due to how quickly a tolerance for Phenibut is built, it is not recommended to take it every day. You should not be taking Phenibut more than twice per week.
Is Phenibut Good for Anxiety?
Phenibut is an anxiolytic supplement meaning that when taken at appropriate doses it promotes many anti-anxiety feelings.
How Long does Phenibut Last?
The peak effects of Phenibut take 4 to 6 hours to feel but may last up to 10 hours.
Should you take Phenibut on an Empty Stomach?
It is best to take Phenibut on an empty stomach as taking it with food will extend the already considerably long time it takes to start working after ingestion.
Is Phenibut safe to take while pregnant?
It is not recommended for anyone who is pregnant to take Phenibut. Since tolerance builds so quickly, symptoms of withdrawal can have negative effects on both the expectant mother and child.
* These reviews are the experiences of the individual customers that submitted them, results may differ from person to person.
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