What it is
A synthetic GABA derivative with an added phenyl ring developed in the Soviet Union. Regulatory status varies by jurisdiction; not FDA-approved in the US and subject to import restrictions and state-level scheduling.
How it works
Acts as an agonist at GABA-B receptors and, at higher concentrations, GABA-A receptors. Also blocks alpha-2-delta calcium channels at higher doses.
Where it's used
Used as a prescription medication in some former Soviet states for anxiety and related indications. Not approved as a medication in the US.
Regulatory status
Not FDA-approved. Regulatory status varies; restricted or scheduled in several jurisdictions.
Tracking it
Phenibut is oral, which makes consistency the whole game — a simple daily check-off with a reminder beats memory every time. with a half-life of about 5.3 hours, a dose log also lets a tracker model the relative amount still in your system between doses.
Source
Public reference
Last reviewed 2026-06-11