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CompoundIQ publishes research summaries for informational and educational purposes only. Nothing on this site constitutes medical advice, diagnosis, or treatment recommendations. Always consult a licensed healthcare provider. Many compounds listed are research chemicals not approved for human use.

OtherAdvancedHigh Risk

Phenibut

Also known as: Fenibut, Anvifen, Noofen, PhGABA

Phenibut is a GABA-B agonist and alpha-2-delta voltage-dependent calcium channel blocker developed in Russia in the 1960s. While it produces potent anxiolytic and social enhancement effects, it carries significant risks of rapid tolerance, physical dependence, and a dangerous withdrawal syndrome that can include seizures.

Evidence45/100 — Emerging

Risk Level

High Risk

Difficulty

Advanced
CAS Number1078-21-3
Molecular FormulaC10H13NO3
ClassOther
CategoryNootropics

Mechanism of Action

Phenibut is a phenylated analog of GABA that crosses the blood-brain barrier due to its phenyl ring. It acts as a GABA-B receptor agonist (similar to baclofen) and blocks alpha-2-delta subunit of voltage-dependent calcium channels (similar to gabapentin/pregabalin). At higher doses it also activates GABA-A receptors. This dual mechanism produces anxiolytic, muscle-relaxant, and euphoric effects.

Dosing Research

Typical dose: 250-1000 mg, used no more than 1-2 times per week to avoid dependence. Onset: 2-4 hours. Duration: 6-10 hours. Do NOT use daily — physical dependence can develop within 5-7 days of consecutive use. Tolerance escalation is rapid and dangerous. Never combine with alcohol, benzodiazepines, or other CNS depressants.

Side Effects & Risks

HIGH RISK: Rapid tolerance and physical dependence with daily use. Withdrawal can be severe and life-threatening — includes anxiety, insomnia, psychosis, tremors, and seizures. Sedation, dizziness, nausea at higher doses. Rebound anxiety worse than baseline. Has caused hospitalizations and deaths when combined with other depressants. Banned or restricted in several countries/states.

Research Studies

Disclaimer

CompoundIQ publishes research summaries for informational and educational purposes only. Nothing on this site constitutes medical advice, diagnosis, or treatment recommendations. Always consult a licensed healthcare provider. Many compounds listed are research chemicals not approved for human use.

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