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Dietary supplement

Pure Phenibut Pharma Grade Powder Ingredients & Drug Interactions

by Hard Rhino

Pure Phenibut Pharma Grade Powder label
See full label image
Powder Category: Non-nutrient/non-botanical
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Pure Phenibut Pharma Grade Powder against your medications. The heart of this page is the interaction checker and the full interaction report — how this product’s ingredients may interact with prescription and over-the-counter medicines you may be taking.

Around that, we add a pharmacist’s high-level view of the product as a whole — what’s inside, the evidence for its stated use, how transparent the label is, and what safety data exists — so you can see the full picture in one place. It’s educational information from our licensed clinical databases and the clinical staff at HelloPharmacist — not medical advice — and we don’t sell or endorse products. Our editorial policy

The interaction bottom line Most serious interaction: Moderate

Pure Phenibut Pharma Grade Powder is a dietary supplement by Hard Rhino with 1 active ingredient. Its ingredients are commonly taken for anxiety and stress, insomnia and sleep problems, stress relief.Based on those ingredients, 248 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Phenibut. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Pure Phenibut Pharma Grade Powder by Hard Rhino

Ask about any prescription or over-the-counter medication and we check it for interactions with Pure Phenibut Pharma Grade Powder by Hard Rhino — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Pure Phenibut Pharma Grade Powder by Hard Rhino

Our pharmacy team’s full take, with four database checks built into the cards below — a summary of what is known, not a grade of the product itself.

From our pharmacy team — supplement deep dive

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Jul 11, 2026

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 1 of its 1 active ingredient.
  • No proprietary blends here — you can verify the dose of every single component.

This product contains one active ingredient: phenibut, a compound that acts on GABA receptors in the brain. It's sold as a powder with no other active ingredients.

Does it work?

Couldn't assess
Evidence for Intended Use · database check
By FDA rules, dietary supplements can’t claim to treat, cure, or prevent disease — so labels speak in careful marketing language. We discern each product’s intended use from its name, label claims, and label statements, then grade the clinical evidence for that use. How these ratings are computed
Not assessable

This is a single-ingredient Phenibut product and its label doesn't state a use — see Phenibut's own graded uses on its monograph.

Why this rating?
  • We looked at the product name, claims, and label statements and couldn't find a stated purpose to grade.

The evidence we hold does not establish that phenibut is effective for any condition. It's listed as having insufficient reliable evidence for alcohol use disorder, anxiety, ADHD, cognitive function, depression, and insomnia.

Right now, we cannot tell you whether it works.

The evidence, ingredient by ingredient Phenibut

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

Adverse-effect, pregnancy, and general safety data are on file for most of these ingredients.

Why this rating?
  • We hold adverse-effect (side-effect) data for 1 of the 1 matched ingredient.
  • Pregnancy & breastfeeding safety ratings cover 1 of 1.
  • General safety write-ups exist for 1 of 1.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Phenibut carries a high risk of dependence and dangerous withdrawal — both short- and long-term use can be problematic. Most common side effects include dizziness, drowsiness, nausea, and balance problems.

Withdrawal symptoms (agitation, anxiety, seizures, rapid heartbeat, and others) can start after just 3 or more consecutive days of use. At high doses, it's been linked to respiratory depression (shallow breathing).

Serious effects in case reports include hallucinations, altered mental status, and coma. Phenibut is not approved as a supplement or drug in the U.S., and the safety data advises against it in pregnancy and breastfeeding.

Side effects, ingredient by ingredient Phenibut

Meds to double-check

Moderate interaction found
Known Interaction Concern · database check
Moderate identified

The most serious documented interaction for these ingredients is Moderate. Check your medications for a personalized result.

Why this rating?
  • 1 of the 1 matched ingredient can interact with medications — Phenibut.
  • The most serious interaction on file is rated Moderate.
  • For scale: 248 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Do not combine phenibut with CNS depressants (sedatives, sleep aids, opioids, benzodiazepines, or alcohol) — it raises the risk of dangerous sedation and respiratory depression (Moderate severity). Also avoid combining it with pregabalin (Lyrica) for nerve pain.

Check your exact medications below before considering this product.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with no assessable stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.

Phenibut is not approved in the U.S. and carries significant risks of dependence, dangerous withdrawal, and serious side effects — even with short use. If you're considering it for anxiety, sleep, or another condition, talk to your pharmacist or doctor first.

This is not a product to take lightly or without professional guidance.

Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI

Assessment coverage: 1 of 1 active ingredient matched to our full ingredient reviews (monographs). Based on the product label dated Jun 25, 2014.

This Scorecard evaluates available label information, ingredient evidence, and known medication-safety considerations. It does not independently verify product identity, purity, potency, contamination, or manufacturing quality. How these ratings are computed

At a glance

General information

Key facts about Pure Phenibut Pharma Grade Powder, straight from the product label.

Brand Hard Rhino
Net contents 125 Gram(s); 4.4 oz.
Market status On market
Date entered into DSLD Jun 25, 2014
DSLD ID 34535
Product type Non-nutrient/non-botanical
Supplement form Powder
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Gluten Free, Dairy Free
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for Pure Phenibut Pharma Grade Powder by Hard Rhino, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
250 mg
Maximum serving Sizes:
1500 mg
Servings per container
500
IngredientAmount% DV
Phenibut250 mg--

Other ingredients: Phenibut Pharma Grade Powder

Tap any ingredient to jump to its full detail below.

Label statements
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
FDA Disclaimer Statement

Disclaimer: These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.

Precautions

WARNING: A scale is required for accurate measurements.

Keep away from children.

Do not take this or any other supplement if you are pregnant or nursing.

WARNING: A micro scale is required for accurate measurements.

Do not take this or any other supplement if you are pregnant or nursing, have high blood pressure or taking other prescription drugs.

Do not take if you have high blood pressure or any medical complications.

Formulation

No added fillers No flow agents No driers No other ingredients

Allergens: This product contains NO Soy, Milk & Byproducts, Eggs, Fish, Shellfish, Wheat, Gluten, Tree Nuts, or Sesame Seeds.

Suggested/Recommended/Usage/Directions

Suggested Use: Typical dosage is between 250 to 1500 mg. twice daily. It is highly recommended that Phenibut not be consumed more than 2 days per week. As with all of our powders, a micro scale is strongly recommended for proper dosage.

Suggested Use: Typical dosages are between 250mg to 1500mg twice daily. It is recommended to not consume more than 2 days per week.

Storage

Storage: Store in a cool & dry place. Keep away from strong light & heat.

Storage: Sore in a cool & dry place. Keep away from direct sunlight and heat.

General Statements

USP-FCC

This is a NON-GMO ingredient produced with organic material.

Always consult with a physician before taking any new dietary supplement.

Quality Healthcare Worldwide

Always consult with your physician before taking any new dietary supplements. Expiration date on back of pouch.

Is this label outdated? Report a formula or label change and our pharmacy team will review it.

See for yourself

Pure Phenibut Pharma Grade Powder by Hard Rhino label

The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.

Pure Phenibut Pharma Grade Powder label

Label images are published by the NIH Dietary Supplement Label Database for the version of this product on file. Always read your actual product label.

View the full label (PDF)
What’s inside

The Ingredients in Pure Phenibut Pharma Grade Powder by Hard Rhino

This is the 1 active ingredient this product is made of. Select it to open its full monograph.

Serving size250 mg Dosage formPowder Servings per container500 Amounts shown are per serving.

Phenibut

Interacts with
248 drugs
250 mg per serving

Phenibut is a synthetic, lab-made central nervous system depressant—not a natural herb—that some people use for anxiety and sleep, but it carries a se...

Phenibut monograph & interactions

Other (inactive) ingredients: Phenibut Pharma Grade Powder. These complete the product’s ingredient list but are not active constituents.

Interaction report

Pure Phenibut Pharma Grade Powder by Hard Rhino Drug Interactions

Want to check YOUR meds against Pure Phenibut Pharma Grade Powder?

Ask about interactions with your drugs in plain English — “Can I take it with lisinopril?” — and we find you the answer in seconds, ingredient by ingredient.

 Go to the checker
248Drugs
248 Moderate

Ingredients driving the most interactions

Phenibut 248

Individual Drug Interactions

The ingredients in Pure Phenibut Pharma Grade Powder interact with 248 drugs. Click any drug to see the details.

1 of the 1 ingredient in Pure Phenibut Pharma Grade Powder interact with drugs. Each result below shows which ingredient is responsible. Phenibut

Each ingredient & the kinds of drugs it affects

For each ingredient in Pure Phenibut Pharma Grade Powder with known interactions, here are the types of medications it can affect. Open any type for the detail — or search your exact drug in the checker above.

Phenibut2 drug types · 248 drugs

Cns Depressants

Theoretically, phenibut might increase the risk of sedation and respiratory depression when taken with CNS depressants.
Phenibut has been associated with sedation and respiratory depression in several case reports, especially when taken at high doses.

Likelihood Possible Evidence D
Pregabalin (Lyrica)

Theoretically, phenibut might increase the risk for additive adverse effects, including sedation, when taken with pregabalin.
Phenibut is structurally related to pregabalin, and both chemicals act at GABA receptors in the brain. In a case report, a patient who had experienced tolerance to the effects of pregabalin for treatment of chronic neuropathic pain experienced a reduction in tolerance when phenibut was taken concurrently.

Likelihood Possible Evidence D
Phenibut full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Pure Phenibut Pharma Grade Powder, from the product label.

Hard Rhino

See all Hard Rhino products
Name
GUARDIAN Biosciences
City
Phoenix
State
Arizona
Pharmacist Counseling Corner

Pure Phenibut Pharma Grade Powder by Hard Rhino: Common Questions

Does Pure Phenibut Pharma Grade Powder by Hard Rhino interact with any medications?
Yes. Based on its ingredients, Pure Phenibut Pharma Grade Powder has a known interaction with 248 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Pure Phenibut Pharma Grade Powder contains a single active ingredient, and that one ingredient can interact with many different medications on its own. We check it against each medication and show the mechanism responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Is phenibut approved by the FDA?
No. Phenibut is not approved as a supplement or drug in the U.S. It's sold as a dietary ingredient, but it carries significant safety and dependence risks.
Can I take this if I'm pregnant or breastfeeding?
No. The safety data advises against phenibut in pregnancy because there's no safety data and it's a central nervous system depressant. For breastfeeding, it's unknown whether phenibut passes into breast milk, so it should also be avoided.
How fast can dependence develop?
Very fast. Phenibut can develop tolerance within 3 days, and withdrawal symptoms (agitation, anxiety, seizures, insomnia, and others) can begin after 3 or more consecutive days of use.
What are the most common side effects?
Dizziness, drowsiness, nausea, balance problems, and lethargy. At high doses, respiratory depression (shallow breathing) has been reported. Serious case reports describe hallucinations, altered mental status, and coma.
Does phenibut actually work for anxiety or sleep?
The evidence we hold shows insufficient reliable data to rate it for anxiety, insomnia, or other conditions. We can't tell you whether it's effective.
What happens if I stop taking phenibut after a few days?
Withdrawal symptoms can occur after 3 or more consecutive days of use, including agitation, anxiety, depression, insomnia, nausea, seizures, and rapid heartbeat. This is a serious concern with this product.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

Not sure if Pure Phenibut Pharma Grade Powder is safe with your meds?

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Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.

Pure Phenibut Pharma Grade Powder label
Go deeper

The Full Monographs Behind Pure Phenibut Pharma Grade Powder’s Ingredients

Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.

Herb & supplement monograph

Phenibut

Interacts with 248 drugs

Phenibut is a synthetic, lab-made central nervous system depressant—not a natural herb—that some people use for anxiety and sleep, but it carries a serious risk of tolerance, dependence, and...

Read the full Phenibut monograph →
Sources

Sources & How We Checked

Pure Phenibut Pharma Grade Powder's label data comes from the NIH Dietary Supplement Label Database; the ingredient interaction data is from the Natural Medicines database, reviewed by our pharmacists.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

The 23 references behind this product’s interaction data

Every citation that drives the interaction findings for this product’s ingredients, from the evidence-graded Natural Medicines (TRC Healthcare) database. Open an ingredient to browse its citations — links open the study on PubMed or the publisher’s site.

Phenibut 23 references
  1. Downes MA, Berling IL, Mostafa A, Grice J, Roberts MS, Isbister GK. Acute behavioural disturbance associated with phenibut purchased via an internet supplier. Clin Toxicol (Phila). 2015;53(7):636-8. PubMed
  2. Samokhvalov AV, Paton-Gay CL, Balchand K, Rehm J. Phenibut dependence. BMJ Case Rep. 2013 Feb 6;2013. Pii: bcr2012008381.
  3. O'Connell CW, Schneir AB, Hwang JQ, Cantrell FL. Phenibut, the appearance of another potentially dangerous product in the United States. Am J Med. 2014 Aug;127(8):e3-4. PubMed
  4. Brunner E, Levy R. Case report of physiologic phenibut dependence treated with a phenobarbital taper in a patient being treated with buprenorphine. J Addict Med. 2017 May/Jun;11(3):239-40. PubMed
  5. Sankary S, Canino P, Jackson J. Phenibut overdose. AM J Emerg Med. 2017 Mar;35(3):516.e1-516.e2.
  6. Owen DR, Wood DM, Archer JR, Dargan PI. Phenibut (4-amino-3-phenyl-butyric acid): Availability, prevalence of use, desired effects, and acute toxicity. Drug Alcohol Rev. 2016 Sep;35(5):591-6. PubMed
  7. Magsalin RM, Khan AY. Withdrawal symptoms after internet purchase of phenibut (beta-phenyl-gamma-aminobutyric acid HCl). J Clin Psychopharmacol. 2010 Oct;30(5):648-9.
  8. Rod W, Kudryk A, Brunetti L, Sun N, Nguyen M. Phenibut withdrawal management in the setting of concomitant kratom and alcohol dependence. Critical Care Med 2018;46(1):451.
  9. Li W, Madhira B. Phenibut (beta-phenyl-gamma-aminobutyric acid) psychosis. Am J Therapeut 2017;24(5):e639-640.
  10. Joshi Y, Friend S, Jimenez B, Steiger L. Dissociative intoxication and prolonged withdrawal associated with phenibut: a case report. J Clin Psychopharmacol 2017;37(4):478-80. PubMed
  11. Zheng KH, Khan A, Espiridion ED. Phenibut addiction in a patient with substance use disorder. Cureus. 2019;11(7):e5230. PubMed
  12. Hardman MI, Sprung J, Weingarten TN. Acute phenibut withdrawal: A comprehensive literature review and illustrative case report. Bosn J Basic Med Sci. 2019;19(2):125-129. PubMed
  13. Ahuja T, Mgbako O, Katzman C, Grossman A. Phenibut (β-Phenyl-γ-aminobutyric Acid) dependence and management of withdrawal: Emerging nootropics of abuse. Case Rep Psychiatry. 2018;2018:9864285.
  14. Isoardi KZ, Kulawickrama S, Isbister GK. Severe phenibut poisoning: An adolescent case cluster. J Paediatr Child Health. 2020;56(2):330-331. PubMed
  15. McCabe DJ, Bangh SA, Arens AM, Cole JB. Phenibut exposures and clinical effects reported to a regional poison center. Am J Emerg Med. 2019;37(11):2066-2071. PubMed
  16. Graves JM, Dilley J, Kubsad S, Liebelt E. Notes from the field: phenibut exposures reported to poison centers - United States, 2009-2019. MMWR Morb Mortal Wkly Rep 2020;69(35):1227-8. PubMed
  17. Tamarelli C, Hosanagar A. Phenibut use in a patient prescribed gabapentinoids (letter). Pain Med 2020; Aug 4:pnaa205. doi: 10.1093/pm/pnaa205. PubMed
  18. Esposito CM, Mandolini GM, Delvecchio G, Fiorentini A, Brambilla P. Psychomotor agitation non-responsive to treatment: a case report of phenibut withdrawal syndrome. Front Psychiatry 2021;12:688147. PubMed
  19. Acosta E, Munguti C. Acute Psychosis Associated with Phenibut Ingestion. Kans J Med 2021;14:308-309. PubMed
  20. VanDreese B, Holland A, Murray A. Chronic Phenibut Use: Symptoms, Severe Withdrawal, and Recovery. WMJ 2022;121(1):E1-E4.
  21. 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. PubMed
  22. Morris M, Espinosa J, Lucerna A, Lahr R. A case of phenibut withdrawal and treatment with baclofen. World J Emerg Med 2023;14(4):338-340. PubMed
  23. DiFiore E, Pittman J. A Case of Phenibut Withdrawal Management and Detoxification Using Baclofen in the Outpatient Setting. Case Rep Psychiatry 2024;2024:8824770. PubMed

See these in context on the Phenibut monograph →

Parts of this content are provided by the Therapeutic Research Center, LLC.

DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

© 2021 Therapeutic Research Center, LLC

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