Phenibut
Monograph · CPhenibut
GABA-B receptor agonist with secondary calcium-channel modulation. Soviet-developed anxiolytic + sleep aid.
How it clearsHalf cleared in ~5h. Most (~96%) gone by ~1d.
Compare these compounds
Mechanism, evidence, legal path, cost — all side-by-side.
This compound sits in research-grey territory. The caveats below carry more weight than for FDA-approved entries — read them.
β-phenyl-γ-aminobutyric acid. Crosses the blood-brain barrier where GABA itself cannot. Acts primarily on GABA-B receptors (Baclofen-class binding); at higher doses also on GABA-A. Russian-published clinical use since 1975 for anxiety, sleep onset, and ethanol withdrawal — sparse Western trial data. Tolerance develops fast (within 5-7 days of consecutive dosing) and withdrawal at therapeutic-range doses can be severe and prolonged. Not classified as a controlled substance federally in the US, but banned in Australia and several US states.
Promising cognitive signal that holds up in early trials — but cognitive effects resist self-assessment at low deltas. The brain adjusts to its own baseline quickly, meaning real improvements can feel like nothing from the inside. Task performance tracks better than sensation here.
TOLERANCE + WITHDRAWAL ARE THE PRIMARY RISK. Consecutive-day dosing builds tolerance within a week; abrupt cessation can produce severe anxiety, insomnia, dysphoria, and seizures lasting weeks. Treat phenibut like alcohol: weekend-only at most, never as a daily nootropic. Never combine with alcohol, benzodiazepines, opioids, or barbiturates — all act on GABA pathways and respiratory depression risk multiplies. Banned in Australia, Hungary, Italy, Lithuania, Russia (Rx-only), and several US states.
Upload your data to see how it relates to Phenibut.
Upload a lab file (LabCorp / Quest) or DNA file (23andMe / AncestryDNA). Stack will show your specific markers alongside the literature-reported response windows.
Upload in /historyPer-claim grading. Each claim is graded independently — same peptide, different claims can carry different grades.
- CLimited evidence
GABA-B receptor agonist with secondary calcium-channel modulation
1 supporting referencesVerified 23d ago
External links to PubMed searches, ClinicalTrials.gov, and FDA materials. We do not host papers — we point at canonical sources.
- PubMedENREVIEWFunding undisclosedVerified 48d agoPubMed — Phenibut clinical literature
- PubMedENREVIEWAcademic-fundedVerified 48d agoLapin IP — Phenibut: discovery, characterization, pharmacology (CNS Drug Reviews 2001)
- RegulatoryENREGULATORYNIH-fundedVerified 48d agoFDA Warning — Phenibut as unapproved new drug + dietary-ingredient violation
Not FDA-approved. Not a controlled substance federally. State-level bans: see /can-i-get-it.
Distilled themes from named communities — Reddit threads, forums, creator commentary. Not direct quotes; not clinical evidence. Useful for calibrating expectations against what real self-experimenters report.
Self-reports converge on phenibut working too well and withdrawal hitting too hard. Cohort consensus: weekend-only, never stack consecutive days, never combine with alcohol.
Next visit & citations
Handoff & sources
Running this compound? Log it in /history, then open Dr Passport before your visit. Methodology explains grades; the research dashboard sorts the full catalog with citations.