Drug & supplement interaction

1,4-butanediol + Ethanol

Ethanol brand name: Ethanol.

Major Interaction
The bottom line Major

1,4-butanediol has a major interaction with Ethanol. Theoretically, alcohol may increase or decrease the therapeutic and adverse effects of 1,4-butanediol.

Read the full interaction report
SeverityMajor
LikelihoodProbable
EvidenceC
What do Severity, Likelihood & Evidence mean?
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Interaction report

1,4-butanediol and Ethanol

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

Major

ALCOHOL (Ethanol)

Theoretically, alcohol may increase or decrease the therapeutic and adverse effects of 1,4-butanediol.
1,4-Butanediol is metabolized to gamma-hydroxybutyrate (GHB) by hepatic alcohol dehydrogenase enzymes. Alcohol competitively inhibits alcohol dehydrogenase, which leads to higher blood levels of 1,4-butanediol and lower blood levels of GHB. The clinical effects of this change are not well understood. Most researchers believe that the pharmacologic activity of 1,4-butanediol is dependent on conversion to GHB; however, animal research shows that 1,4-butanediol may also act independently. Also, in humans, concomitant use of GHB and alcohol increases the adverse effects of GHB, possibly by reducing the elimination of GHB. Concomitant use of GHB and alcohol may also cause additive respiratory and central nervous system depression. Therefore, concomitant use of 1,4-butanediol and alcohol may either increase or decrease the risk of adverse effects.
Severity Major Likelihood Probable Evidence C

Interaction 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..

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

Let me be blunt here, because this one really matters. 1,4-butanediol is not a real supplement, it is a toxic industrial chemical your body turns into GHB, a heavy central nervous system depressant. Drinking alcohol on top of it is a genuinely dangerous combination.

Alcohol blocks the same enzyme (alcohol dehydrogenase) that converts 1,4-butanediol into GHB, so the timing and levels get unpredictable. What is not unpredictable is the overlap: both alcohol and GHB slow your brain and your breathing. Together they can cause deep sedation, blackout, vomiting, dangerously slow breathing, and coma. Mixing them has been fatal. Please do not combine these. If someone has taken both and seems very drowsy or hard to wake, call 911 right away.

References
  1. Anon. Adverse events associated with ingestion of gamma-butyrolactone--Minnesota, New Mexico, and Texas, 1998-1999. MMWR Morb Mortal Wkly Rep 1999;48:137-40.
  2. Anon. FDA alert on misuse of consumer products containing GHB, GBL and BD. Food and Drug Administration, Rockville, MD. June 15, 1999.
  3. Poldrugo, F., Barker, S., Basa, M., Mallardi, F., and Snead, O. C. Ethanol potentiates the toxic effects of 1,4-butanediol. Alcohol Clin.Exp.Res 1985;9(6):493-497. PubMed
  4. 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
  5. Product information for Xyrem. Jazz Pharmaceuticals, Inc. Palo Alto, CA. March 2022.
  6. Liakoni E, Gugelmann H, Dempsey DA, et al. Butanediol conversion to gamma-hydroxybutyrate markedly reduced by the alcohol dehydrogenase blocker fomepizole. Clin Pharmacol Ther 2019;105(5):1196-203. doi: 10.1002/cpt.1306. PubMed

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

1,4-butanediol Also Interacts With Other Medications

1,4-butanediol has 249 major, 21 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.

Taking anything else?

Check Another of Your Medications Against 1,4-butanediol

Covers the 2,830 medications we’ve checked against 1,4-butanediol. Pick one to open its full report.

Everything else you take

See Every Supplement That Interacts With Ethanol

This page covers 1,4-butanediol 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: Activated Charcoal (major), Coca (major), Gamma-hydroxybutyrate (ghb) (major), Tansy (major) and Bilberry (moderate).

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 1,4-butanediol 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 1,4-butanediol
Top half

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

29 days ago today
Medication Ethanol
Top 5%

#137 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 1,4-butanediol

What is 1,4-butanediol?

  • Marketed illegally as a 'recreational' or party substance
  • Falsely sold as a sleep aid
  • Falsely promoted for bodybuilding or muscle growth
  • Industrial solvent and chemical manufacturing

1,4-butanediol is a toxic industrial chemical, not a safe dietary supplement. Once swallowed, the body converts it into GHB, a powerful central nervous system depressant that can cause coma, dangerous breathing problems, addiction, and death. It should never be taken as a supplement or recreational substance.

Read the full 1,4-butanediol monograph & all interactions
Keep checking

Other Drugs & 1,4-butanediol

Browse every other medication we’ve checked against 1,4-butanediol — both the ones with a known interaction and the ones without. Select any drug for the full detail.

249Major
21Moderate
0Minor
2,559No known interaction
Major

249 interactions

Showing 60 of 249 major interactions — see all 249 on the 1,4-butanediol page.

Moderate

21 interactions

No interaction 2,559 drugs checked — show the list
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

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Pharmacist Counseling Corner

Taking 1,4-butanediol and Ethanol Together: Common Questions

Can you take 1,4-butanediol with Ethanol?
This is rated a major interaction, so the combination is best avoided unless your doctor or pharmacist has specifically told you otherwise. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the 1,4-butanediol and Ethanol interaction?
We rate it Major. This is a clinically significant combination that is generally best avoided, or used only under the direct supervision of your physician or pharmacist.

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

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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.