Drug & supplement interaction

Gamma-hydroxybutyrate (ghb) + Suvorexant

Suvorexant brand name: Belsomra.

Major Interaction
The bottom line Major

Gamma-hydroxybutyrate (ghb) has a major interaction with Suvorexant. GHB may increase the risk of serious CNS and respiratory depression.

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

Gamma-hydroxybutyrate (ghb) and Suvorexant

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

Major

CNS DEPRESSANTS

Why this applies to Suvorexant

Suvorexant falls under CNS DEPRESSANTS — the group Gamma-hydroxybutyrate (ghb) interacts with.

GHB may increase the risk of serious CNS and respiratory depression.
Concomitant use of GHB with CNS depressants may increase the risk of serious CNS and respiratory depression.
Severity Major Likelihood Probable Evidence D

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

Here's the simple version: both suvorexant (Belsomra) and GHB push the brain in the same direction, toward heavy sedation. Suvorexant quiets the wake-promoting orexin signals in your brain, while GHB is a powerful nervous system depressant. Stacking them can pile that calming effect way too high.

Put together, you could see deep drowsiness, confusion, trouble waking up, and the big worry, slowed or stopped breathing. That combination can be dangerous, even life-threatening. I'll be honest, the evidence here is mostly anecdotal, but the risk is serious enough that I wouldn't gamble on it. Keep in mind GHB sold outside a pharmacy is illegal and unpredictable. Please talk with your doctor or pharmacist before mixing anything like this.

References
  1. 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-hydroxybutyrate (ghb) Also Interacts With Other Medications

Gamma-hydroxybutyrate (ghb) has 248 major, 21 moderate, 5 minor known drug interactions in our database — the Suvorexant 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 Gamma-hydroxybutyrate (ghb)

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

From our Q&A

Questions About Gamma-hydroxybutyrate (ghb) or Suvorexant

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Gamma-hydroxybutyrate (ghb) or Suvorexant, not necessarily both, but if one is close to what you were about to ask it will usually go further than a database entry can:

Not quite your question? Ask our pharmacists directly — it is free, there is no account required, and answers usually come back within 24 hours.

Everything else you take

See Every Supplement That Interacts With Suvorexant

This page covers Gamma-hydroxybutyrate (ghb) only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Suvorexant page lists 195 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), Beer (major), Grapefruit (major) and Kava (major).

By severity: 9 major · 147 moderate · 39 minor.

From our pharmacist’s overview on the Suvorexant page

“People take suvorexant (Belsomra) to fall asleep, and the supplements they reach for often promise the same thing, which is exactly the trouble. Of the 195 ingredients with an interaction on file, 78 add their own sedation on top of the drug's, and that theme dominates the 9 rated major, alcohol in any form among them.”

Reviewed by 2 · Jul 18, 2026

Open the Suvorexant interaction page

How much people look this up

Where Gamma-hydroxybutyrate (ghb) and Suvorexant 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-hydroxybutyrate (ghb)
Steady interest

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

29 days ago today
Medication Suvorexant
Steady interest

#2,692 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-hydroxybutyrate (ghb)

What is Gamma-hydroxybutyrate (ghb)?

  • Narcolepsy (cataplexy and excessive daytime sleepiness)
  • Sleep aid
  • Misused as a recreational 'party drug'
  • Bodybuilding/muscle building (unproven)
  • Alcohol withdrawal (in some countries)

GHB (gamma-hydroxybutyrate) is a powerful central nervous system depressant that is NOT a safe dietary supplement. In the U.S. it is a controlled substance, and only a tightly regulated prescription form (sodium oxybate) is legal for narcolepsy. Non-prescription GHB can cause coma, breathing failure, and death, and it is also a known 'date-rape' drug — it should not be taken outside of medical supervision.

Read the full Gamma-hydroxybutyrate (ghb) monograph & all interactions
Medication

About Suvorexant

What Is Suvorexant Used For?

Brand name: Belsomra

Belsomra (suvorexant) is used to treat insomnia — specifically, difficulty falling asleep and/or difficulty staying asleep through the night.

See full Suvorexant drug information
Keep checking

Other Drugs & Gamma-hydroxybutyrate (ghb)

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

248Major
21Moderate
5Minor
2,555No known interaction
Major

248 interactions

Showing 60 of 248 major interactions — see all 248 on the Gamma-hydroxybutyrate (ghb) page.

Moderate

21 interactions

Minor

5 interactions

No interaction 2,555 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

Keep exploring
Pharmacist Counseling Corner

Taking Gamma-hydroxybutyrate (ghb) and Suvorexant Together: Common Questions

Can you take Gamma-hydroxybutyrate (ghb) with Suvorexant?
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 Gamma-hydroxybutyrate (ghb) and Suvorexant 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.