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GABA Analog

Phenibut

A GABA-derivative compound used to reduce anxiety and promote relaxation.

Evidence gradeCross-checked · Moderate-high
B+
WeakModerateStrong
4.0/ 5 rating

KÖGN Health grades Phenibut as B+ (Moderate evidence) and rates it 4.0 out of 5.

Last reviewed · June 2026

CategorySynthetic · GABA Analog
AvailabilityResearch

Primary effects

  • Reduced anxiety
  • Improved mood
  • Relaxation

How it works

Activates GABA-B receptors, producing calming and anxiolytic effects.

Overview

Phenibut is known for its strong anxiolytic effects, making it effective for reducing social anxiety and stress. However, it carries a significant risk of tolerance, dependence, and withdrawal with frequent use. Because of this, it is best used sparingly and not as a daily supplement. It is more aligned with situational or occasional use rather than foundational cognitive enhancement.

The evidence

Phenibut is a GABA-B agonist developed in Russia as an anxiety and sleep aid. It does reduce anxiety, but it is included here mainly as a caution: it carries a serious risk of tolerance, dependence and a severe withdrawal syndrome. Any short-term calming or 'social' benefit is heavily outweighed by that liability.

Safety & side effects

Tolerance builds quickly, and abrupt discontinuation can cause severe withdrawal — anxiety, agitation, insomnia, palpitations and, in serious cases, psychosis requiring hospital care. Sedation and next-day grogginess are common.

Who should avoid it

KÖGN does not recommend phenibut. It is not an approved medicine in most countries, has a high dependence and withdrawal risk, and is dangerous combined with alcohol, sedatives or opioids. If you are already using it regularly, do not stop abruptly — seek medical help to taper.

References

Related ingredients

Graded entries that target the same cognitive goals.

Categories

Synthetic NootropicsStress & Anxiety ReductionMood & Emotional RegulationGABAergics (Calming / Inhibitory Support)Acute Performance NootropicsExperimental / Research CompoundsModerate-High Evidence

Draft — the dose, safety and evidence notes on this entry were prepared from the published literature and are pending editorial and clinical review.

Educational information, not medical advice. The evidence grade is KÖGN’s editorial assessment of published research, not a health claim. Speak to a qualified clinician before changing what you take.