Phenibut (β-phenyl-γ-aminobutyric acid HCl) is structurally similar to GABA (γ-aminobutyric acid), one of the most prevalent inhibitory neurotransmitters in the human central nervous system. Phenibut was synthesized in Russia in 1964, and since then much of the research has come out of Russian research institutions. In Russia, phenibut is used clinically to treat certain psychiatric disorders, alcohol withdrawal, and sleep disturbances.1Anecdotally, phenibut is used by some biohackers to improve sleep quality, and enhance cognition. However, there is no publication demonstrating a nootropic effect of phenibut in healthy adults.

phenibut sturcture

Structure of GABA and Phenibut

Pharmacology of Phenibut

Phenibut was originally designed to be an analog of GABA that is capable of crossing the blood-brain barrier upon oral ingestion. And indeed, the addition of the phenyl ring to GABA, producing phenibut, does allow it to cross the blood-brain barrier.2The effects of phenibut effects are likely due to its effect on GABA signaling pathways - either by directly interacting with GABA receptors or by promoting endogenous GABA release.3

Nootropic Effects of Phenibut

The only studies of nootropic effects for phenibut are in animals. In one study, phenibut was found to enhance the conditioned response to a form of fear/threat learning in mice, at a dose of 5 mg/kg.4There is no evidence for an effect of phenibut on attention, working memory, or long-term memory

Editorial Opinion

The evidence for a nootropic effect of phenibut are described only in mice, and that evidence is not compelling. Furthermore, as many studies are in Russian, it is challenging to interpret the quality of the research done in the space. Additionally, there is little data on the toxic levels, tolerance, and effect of phenibut in healthy adults. For these reasons, we do not recommend the use of phenibut as a nootropic agent.

Emails worth reading.

Once a week, we'll send you the most compelling research, stories and updates from the world of human enhancement.

HVMN Co-founders Michael Brandt and Geoffrey Woo