Phenibut is a central nervous system (CNS) depressant developed in the 1960s in the Soviet Union. It has been used as an anxiolytic and sedative in Russia and Eastern European countries for decades. 

This article reviews the clinical literature to identify the optimal dosage of phenibut for anxiety, taking into consideration both efficacy and safety.

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Pharmacology of Phenibut

Phenibut, chemically known as β-phenyl-γ-aminobutyric acid, is a derivative of the inhibitory neurotransmitter gamma-aminobutyric acid (GABA). It easily crosses the blood-brain barrier and binds to GABA-B receptors, promoting relaxation, reducing anxiety, and improving sleep quality. Phenibut also has some affinity for GABA-A receptors, although its action on these receptors is less well understood.

Phenibut dosage for anxiety

Clinical Literature on Phenibut Dosage for Anxiety

The clinical literature on phenibut dosage for anxiety is relatively scarce, as the drug has not been extensively studied outside of Russia and Eastern Europe. However, there are several clinical trials and case reports that provide valuable insights into the optimal dosage of phenibut for anxiety.

  1. Lapin (2001) conducted a review of Russian literature on phenibut, highlighting its effectiveness in treating anxiety and sleep disorders. According to the review, the typical daily dosage of phenibut for anxiety ranges from 500 to 1500 mg, divided into two or three doses throughout the day. Source: Lapin I. (2001). Phenibut (beta-phenyl-GABA): a tranquilizer and nootropic drug. CNS Drug Reviews, 7(4):471-81.

  2. Shul'gina and Ziablintseva (2008) conducted a study on the anxiolytic effects of phenibut in rats. The authors concluded that a dose of 10 mg/kg of phenibut was effective in reducing anxiety-related behavior. Although this study was conducted on animals, it may provide some guidance for establishing an effective human dosage. Source: Shul'gina GI, Ziablintseva EA. (2008). Effect of the GABA derivative phenibut on learning. Neuroscience and Behavioral Physiology, 38(3): 267-272.

Safety Considerations

While phenibut may be effective in treating anxiety, there are important safety concerns to consider. The drug has a relatively narrow therapeutic window, meaning that the difference between an effective dose and a potentially harmful dose is small.

Phenibut is known to cause tolerance and dependence with prolonged or excessive use. Withdrawal symptoms, including severe rebound anxiety and insomnia, can occur if the drug is discontinued abruptly after regular use. It is crucial to follow recommended dosages and taper off gradually when discontinuing phenibut.

Additionally, phenibut can cause side effects such as dizziness, nausea, headaches, and drowsiness. It is essential to monitor for these side effects and adjust dosage accordingly to ensure safety.

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Conclusion: How much Phenibut for anxiety?

Based on the limited clinical literature, the optimal dosage of phenibut for anxiety appears to range from 500 to 1500 mg per day, divided into two or three doses. However, due to the lack of extensive research and the potential for tolerance, dependence, and adverse effects, phenibut should be used with caution and under the supervision of a healthcare professional.

As more research is needed to establish optimal dosing guidelines and long-term safety, individuals considering phenibut for anxiety should consult with their healthcare provider before beginning treatment. In cases where phenibut is deemed appropriate, it is important to start at the lowest effective dose and closely monitor for side effects or signs of tolerance. If needed, the dosage can be adjusted based on the individual's response and in accordance with healthcare provider recommendations.

It is essential to note that phenibut is not approved for medical use in many countries, including the United States, where it is sold as a dietary supplement. As a result, the quality and purity of phenibut products can vary significantly, further emphasizing the importance of caution and consultation with a healthcare professional before use.

In summary, while phenibut has shown promise in treating anxiety, more research is needed to determine the optimal dosage and establish its long-term safety. Individuals considering phenibut for anxiety should exercise caution, consult with a healthcare provider, and closely monitor for side effects and tolerance.

In the realm of supplements designed to alleviate the symptoms of stress,

Phenibut, a popular anxiolytic and nootropic supplement, has gained attention for its

Phenibut, a potent central nervous system depressant, has garnered considerable attention in

About the Author Chris Fraighten

Chris Fraighten is a leading biomedical researcher and currently the lead author of the Epimodels blog. He holds qualifications in chemistry, biology and is highly experienced in the fields of quantitative modelling and epidemiology. He brings this wealth of knowledge and experience to the Epimodels blog to bring you insightful, informative and interesting content on the latest advances in the space.