Phenibut: What Parents Should Know

Marketed as a “stress reliever” or “sleep aid,” Phenibut is a synthetic drug that acts like a tranquilizer — not a natural supplement.

Acts on GABA receptors. Phenibut was developed in Russia as a prescription anti-anxiety drug. It depresses brain activity similar to benzodiazepines like Valium or Xanax.1–2

Not approved by the FDA. Despite being sold online as a “nootropic,” the FDA ruled phenibut is not a lawful dietary ingredient and has issued multiple warning letters to vendors.3–4

Dependence and withdrawal are common. Regular use can lead to tolerance and severe withdrawal—agitation, hallucinations, tremor, and seizures—often requiring hospitalization.5–8

Sold online with misleading labels. Phenibut appears in powders or capsules labeled “Relax,” “Calm,” or “Focus Boost.” Many are marketed directly to teens under “wellness” branding.

FDA: Phenibut in Dietary Supplements Back to Information Center

Parent Playbook

What to look for. Unmarked white powders or capsules sold online as “Phenibut HCL,” “nootropic,” “anxiety relief,” or “pre-workout focus.”
Behavior changes: fatigue, slurred speech, irritability, or confusion.5–7

If withdrawal hits. Sudden stopping can cause tremors, panic attacks, psychosis, or seizures. Seek emergency care; treatment may include benzodiazepines or supportive detox.6–8

How to talk about it. “Phenibut isn’t a vitamin—it’s a lab-made drug that slows brain activity. People can get hooked fast. Let’s talk to a doctor or pharmacist together.”

Product Examples

Photos courtesy of the U.S. Food and Drug Administration (FDA), Public Domain.

Phenibut supplement bottles shown in FDA safety warning photo
Photo: U.S. Food and Drug Administration (FDA), Public Domain.
Phenibut powder and capsule products marketed as dietary supplements
Photo: U.S. Food and Drug Administration (FDA), Public Domain.
Gas-station supplement packaging labeled as Phenibut or nootropic products
Photo: U.S. Food and Drug Administration (FDA), Public Domain.

Myths vs. Facts

Myth: “It’s natural and safe.”
Fact: Phenibut is a synthetic chemical — not found in nature — with sedative effects similar to prescription tranquilizers.1–2

Myth: “It helps with focus and anxiety.”
Fact: Any short-term calm is offset by rapid tolerance and serious withdrawal risk.5–8

References (Verified)

  1. Lapin I. Phenibut (β-phenyl-γ-aminobutyric acid): a tranquilizer and nootropic drug. CNS Drug Rev. 2001;7(4):471–481. PubMed
  2. U.S. FDA. Phenibut in Dietary Supplements (not a lawful dietary ingredient). 2023. FDA Information Page
  3. Weleff J, Kovacevich A, Burson J, Nero N, Anand A. Clinical Presentations and Treatment of Phenibut Toxicity and Withdrawal: A Systematic Literature Review. J Addict Med. 2023 Jul–Aug 01; 17(4):407–417. doi: 10.1097/ADM.0000000000001141. Epub 2023 Feb 3. PMID: 37579098. PubMed
  4. Martin R, Buffenstein I, Cho D, Kiyokawa M. Toxidrome of an Easily Obtainable Nootropic: A Case Report of Phenibut Intoxication and Withdrawal Delirium. J Clin Psychopharmacol. 2023 Nov–Dec 01; 43(6):507–510. doi: 10.1097/JCP.0000000000001759. Epub 2023 Sep 12. PMID: 37930202. PubMed
  5. Samokhvalov AV, Paton-Gay CL, Balchand K, et al. Phenibut dependence. BMJ Case Rep. Published online 2013. doi: 10.1136/bcr-2012-008381. Full text (ResearchGate PDF)
  6. Gummin DD, et al. 2023 Annual Report of the National Poison Data System (NPDS). Clin Toxicol (Phila). 2024;62(12):e1–e1261. DOI
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