Drug & supplement interaction

Gamma Butyrolactone (gbl) + Ethanol

Ethanol brand name: Ethanol.

Moderate Interaction
Medically reviewed by · Updated September 2026
The bottom line Moderate

Gamma Butyrolactone (gbl) has a moderate interaction with Ethanol. Concomitant use of alcohol may increase the adverse effects of GBL.

Read the full interaction report
SeverityModerate
LikelihoodPossible
EvidenceD
What do Severity, Likelihood & Evidence mean?
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Interaction report

Gamma Butyrolactone (gbl) and Ethanol

Here is the interaction we found between these two, with the evidence behind it.

Moderate

ALCOHOL (Ethanol)

Concomitant use of alcohol may increase the adverse effects of GBL.
GBL is metabolized to gamma-hydroxybutyrate (GHB). In humans, concomitant use of GBL or GHB and alcohol increases the risk of adverse effects, possibly by reducing the elimination of GHB. Concomitant use of GHB and alcohol may also cause additive respiratory and central nervous system depression.
Severity Moderate Likelihood Possible Evidence D

Interaction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists.

Dr. Brian Staiger, PharmD, BCPS
Dr. Brian Staiger explains PharmD, Clinical Pharmacist

Let me be straight with you: this is one of the most dangerous combinations I can think of. GBL is not a supplement at all, it's a toxic solvent that your body rapidly turns into GHB, a heavy sedative. Drinking alcohol on top of it stacks two nervous-system depressants together, and alcohol may also slow how fast your body clears the GHB out.

The result is dangerously additive sedation: deep drowsiness, slowed or stopped breathing, vomiting, blacking out, seizures, coma, and death. Even though the formal evidence here is anecdotal, the real-world danger is very well known and very real. Please do not combine these. If you're struggling with sleep, anxiety, or substance use, talk to a doctor or pharmacist, there are far safer paths.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Soderling E, Le Bell A, Kirstila V, Tenovuo J. Betaine-containing toothpaste relieves subjective symptoms of dry mouth. Acta Odontol Scand 1998;56:65-9.
  2. Anon. FDA alert on misuse of consumer products containing GHB, GBL and BD. Food and Drug Administration, Rockville, MD. June 15, 1999.
  3. Thai D, Dyer JE, Benowitz NL, Haller CA. Gamma-hydroxybutyrate and ethanol effects and interactions in humans. J Clin Psychopharmacol. 2006 Oct;26(5):524-9. PubMed
  4. Heytens L, Neels H, Van Regenmortel N, et al. Near-fatal persistent anion- and osmolal-gap acidosis due to massive gamma-butyrolactone/ethanol intoxication. Ann Clin Biochem 2015;52(Pt 2):283-7. PubMed
  5. Product information for Xyrem. Jazz Pharmaceuticals, Inc. Palo Alto, CA. March 2022.

What These Ratings Mean

Every interaction above is graded three ways — here’s the key to each label.

Severity how clinically significant the interaction is
Major

Clinically significant. Avoid the combination, or use only under close professional supervision.

Moderate

Usually worth avoiding or managing — may need monitoring, a dose change, or timing apart.

Minor

Generally not serious. Be aware of it and mention it to your pharmacist.

Likelihood how strong the evidence is that the interaction actually happens in people
  • LikelyWell-controlled human studies have demonstrated the likely existence of this interaction.
  • ProbableInteraction has not been documented in well-controlled studies, however, the interaction has been demonstrated in some small human studies or in controlled animal studies in conjunction with multiple case reports.
  • PossibleInteraction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists.
  • UnlikelyInteraction has been demonstrated in animal or in lab research but has been shown not to occur in humans.
Evidence the quality of the studies behind the rating (graded A–D)
  • AHigh-quality meta-analysis (quantitative systematic review).
  • BCase-control study.
  • CConsensus.
  • DAnecdotal evidence.

These ratings are for information only. Never start, stop, or otherwise change your therapy before speaking with your provider.

Keep it in perspective

Gamma Butyrolactone (gbl) Also Interacts With Other Medications

Gamma Butyrolactone (gbl) has 270 moderate known drug interactions in our database — the Ethanol one above is one of them. If you take anything else, check it against the full list below.

Moderate 270 No known interaction 2,560 (incl. Ethanol)
Taking anything else?

Check Another of Your Medications Against Gamma Butyrolactone (gbl)

Covers the 2,830 medications we’ve checked against Gamma Butyrolactone (gbl). Pick one to open its full report.

Everything else you take

See Every Supplement That Interacts With Ethanol

This page covers Gamma Butyrolactone (gbl) only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Ethanol page lists 65 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: 1,4-butanediol (major), Activated Charcoal (major), Coca (major), Gamma-hydroxybutyrate (ghb) (major) and Tansy (major).

By severity: 5 major · 38 moderate · 22 minor.

From our pharmacist’s overview on the Ethanol page

“Ethanol used as a medication is still alcohol, and its supplement list calls for real vigilance, starting with the five entries rated major. GHB is the starkest of these, since combining it with alcohol can cause serious sedation, suppressed breathing, and low blood pressure, a risk confirmed in human studies.”

Reviewed by 2 · Jul 18, 2026

Open the Ethanol interaction page

How much people look this up

Where Gamma Butyrolactone (gbl) and Ethanol Sit Against Everything Else

Out of every supplement and medication people look up on HelloPharmacist, here is where these two land this week — and which way each has been moving.

Supplement Gamma Butyrolactone (gbl)
Steady interest

#1,208 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Ethanol
Top 5%

#136 of 2,830 medications looked up here in the last 7 days

29 days ago today

Position among everything looked up on this site, not a measure of how commonly either one is used or how important it is. A supplement can climb this list because of a news story. It counts every request to the page, automated ones included, and nothing here identifies anyone.

Supplement

About Gamma Butyrolactone (gbl)

What is Gamma Butyrolactone (gbl)?

Gamma Butyrolactone (gbl)
  • Recreational intoxication and euphoria
  • Relaxation and sedation
  • Sleep aid (misused)
  • Bodybuilding/muscle building claims (unproven)
  • Industrial solvent and cleaner

Gamma butyrolactone (GBL) is a toxic industrial solvent, not a dietary supplement, and the body converts it into GHB, a powerful and dangerous sedative. It is illegal to sell or possess for human use in the United States, has no proven medical or supplemental benefit, and can cause coma, seizures, and death. Do not take GBL — if you are seeking help for sleep, anxiety, or substance use, talk to a doctor or pharmacist.

Read the full Gamma Butyrolactone (gbl) monograph & all interactions
Keep checking

Other Drugs & Gamma Butyrolactone (gbl)

Browse every other medication we’ve checked against Gamma Butyrolactone (gbl) — both the ones with a known interaction and the ones without. Select any drug for the full detail.

0Major
270Moderate
0Minor
2,559No known interaction
270 Moderate 2,559 No interaction
Moderate

270 interactions

Showing 60 of 270 moderate interactions — see all 270 on the Gamma Butyrolactone (gbl) page.

No interaction 2,559 drugs checked — show the list

We also checked Gamma Butyrolactone (gbl) against these medications and found no known interaction in our sources. Open any page to confirm.

Showing the 60 most looked-up of 2,559 medications checked with no known interaction — see the full Gamma Butyrolactone (gbl) list.

See the full Gamma Butyrolactone (gbl) interactions page
See every supplement checked against Ethanol, ranked by severity
Sources

Sources & How We Checked

Interaction details are evidence-graded and sourced from the Natural Medicines database. The medication overview comes from MedlinePlus.

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

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

Keep exploring
Gamma Butyrolactone (gbl) monograph › Uses, safety, and every drug interaction in one place Ethanol supplement interactions › Every supplement checked against Ethanol, ranked by severity Supplement interaction checker › Check any supplement or product against your medications Browse medications A–Z › Every drug we've checked against herbs & supplements Ask a pharmacist › Free, personal answer from our licensed team
Pharmacist Counseling Corner

Taking Gamma Butyrolactone (gbl) and Ethanol Together: Common Questions

Can you take Gamma Butyrolactone (gbl) with Ethanol?
There is a moderate interaction, so it may be acceptable with monitoring or timing changes — but check with your pharmacist first. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the Gamma Butyrolactone (gbl) and Ethanol interaction?
We rate it Moderate. This combination may require monitoring, a dose adjustment, or separating the times you take each one. Consult your pharmacist before using them together.

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

Still Have a Question About Ethanol and Gamma Butyrolactone (gbl)?

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This information is for education only and is not a substitute for professional medical advice. Always check with your pharmacist or doctor before starting, stopping, or combining supplements and medications.