Drug & supplement interaction

Grapefruit + Chlordiazepoxide, Clidinium Bromide

Chlordiazepoxide, Clidinium Bromide brand name: Librax.

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

Chlordiazepoxide, Clidinium Bromide falls into 2 drug categories that Grapefruit can interact with; the most serious is rated major. Grapefruit juice might increase blood levels of some oral benzodiazepines, potentially increasing the effects and adverse effects of these drugs.

Read the full interaction report
SeverityMajor
LikelihoodLikely
Interactions2
EvidenceB
What do Severity, Likelihood & Evidence mean?
Know someone taking this? Share
Facebook Post Reddit Email
On this page
Interaction report

Grapefruit and Chlordiazepoxide, Clidinium Bromide

These two interact in 2 distinct ways. Each one is explained separately below.

Why Are There 2 Interactions?

Grapefruit interacts with whole categories of medication. Chlordiazepoxide, Clidinium Bromide falls into 2 of those categories, so it can interact with Grapefruit in 2 different ways. We’ve listed each one below — your overall risk is driven by the most serious of them (Major).

Major

BENZODIAZEPINES

1 of 2

Why this applies to Chlordiazepoxide, Clidinium Bromide

Chlordiazepoxide, Clidinium Bromide falls under BENZODIAZEPINES — the group Grapefruit interacts with.

Grapefruit juice might increase blood levels of some oral benzodiazepines, potentially increasing the effects and adverse effects of these drugs.
Clinical research shows that grapefruit juice can increase plasma triazolam concentrations. Repeated consumption of grapefruit juice greatly increases triazolam concentrations and prolongs the half-life, probably due to inhibition of cytochrome P450 3A4 (CYP3A4). Some studies show that grapefruit juice, particularly when taken in large quantities, reduces the clearance and increases the maximum blood levels, area under the plasma concentration curve (AUC), and duration of effect of midazolam. However, there is no effect on intravenous midazolam. Grapefruit juice has also been shown to increase the maximum blood levels and duration of effect of diazepam, but the clinical significance of this is not known. This interaction does not appear to occur with alprazolam.
Severity Major Likelihood Likely Evidence B

Well-controlled human studies have demonstrated the likely existence of this interaction.

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

Here's the gist: the chlordiazepoxide part of Librax is a benzodiazepine, and your liver clears it using an enzyme called CYP3A4. Grapefruit slows that enzyme down, so the drug can hang around longer and build up to higher levels than expected. In plain terms, grapefruit doesn't weaken Librax, it can amplify it.

If that happens, you may feel more of the usual effects, things like extra drowsiness, dizziness, grogginess, or feeling unsteady on your feet. The effect tends to be bigger with regular or large amounts of grapefruit or its juice rather than an occasional bite. This is a well-recognized class effect, though the exact size for chlordiazepoxide isn't pinned down. Before mixing the two regularly, please check with your pharmacist or doctor.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Ozdemir M, Aktan Y, Boydag BS. Interaction between grapefruit juice and diazepam in humans. Eur J Drug Metab Pharmacokinet 1998;23:55-9. PubMed
  2. Fuhr U. Drug Interactions with Grapefruit Juice. Drug Saf 1998;18:251-72. DOI
  3. Lilja JJ, Kivisto KT, Backman JT, Neuvonen PJ. Effect of grapefruit juice dose on grapefruit juice-triazolam interaction: repeated consumption prolongs triazolam half-life. Eur J Clin Pharmacol 2000;56:411-5. PubMed
  4. Greenblatt DJ, von Moltke LL, Harmatz JS. Time course of recovery of cytochrome P450 3A function after single doses of grapefruit juice. Clin Pharmacol Ther 2003;74:121-29 . PubMed
  5. Veronese ML, Gillen LP, Burke JP, et al. Exposure-dependent inhibition of intestinal and hepatic CYP3A4 in vivo by grapefruit juice. J Clin Pharmacol 2003;43:831-9. . PubMed
  6. Farkas D, Oleson LE, Zhao Y, et al. Pomegranate juice does not impair clearance of oral or intravenous midazolam, a probe for cytochrome P450-3A activity: comparison with grapefruit juice. J Clin Pharmacol 2007;47:286-94. PubMed
  7. Potential drug interactions with grapefruit. Pharmacist's Letter / Prescriber's Letter 2007;23(2):230204.
  8. Yasui N, Kondo T, Furukori H, et al. Effects of repeated ingestion of grapefruit juice on the single and multiple oral-dose pharmacokinetics and pharmacodynamics of alprazolam. Psychopharmacology (Berl) 2000;150:185-90. PubMed
  9. Andersen, V., Pedersen, N., Larsen, N. E., Sonne, J., and Larsen, S. Intestinal first pass metabolism of midazolam in liver cirrhosis --effect of grapefruit juice. Br J Clin Pharmacol 2002;54(2):120-124. PubMed
  10. Hukkinen, S. K., Varhe, A., Olkkola, K. T., and Neuvonen, P. J. Plasma concentrations of triazolam are increased by concomitant ingestion of grapefruit juice. Clin Pharmacol Ther 1995;58(2):127-131. PubMed
  11. Kupferschmidt, H. H., Ha, H. R., Ziegler, W. H., Meier, P. J., and Krahenbuhl, S. Interaction between grapefruit juice and midazolam in humans. Clin Pharmacol Ther 1995;58(1):20-28. PubMed
  12. Culm-Merdek, K. E., von Moltke, L. L., Gan, L., Horan, K. A., Reynolds, R., Harmatz, J. S., Court MH, and Greenblatt, D. J. Effect of extended exposure to grapefruit juice on cytochrome P450 3A activity in humans: comparison with ritonavir. Clin Pharmacol
  13. Sugimoto, K., Araki, N., Ohmori, M., Harada, K., Cui, Y., Tsuruoka, S., Kawaguchi, A., and Fujimura, A. Interaction between grapefruit juice and hypnotic drugs: comparison of triazolam and quazepam. Eur J Clin Pharmacol 2006;62(3):209-215. PubMed
  14. Tanaka S, Uchida S, Miyakawa S, Inui N, Takeuchi K, Watanabe H, Namiki N. Comparison of inhibitory duration of grapefruit juice on organic anion-transporting polypeptide and cytochrome P450 3A4. Biol Pharm Bull. 2013;36(12):1936-41. PubMed
  15. Kawaguchi-Suzuki M, Nasiri-Kenari N, Shuster J, et al. Effect of low-furanocoumarin hybrid grapefruit juice consumption on midazolam pharmacokinetics. J Clin Pharmacol. 2017 Mar;57(3):305-11. PubMed
Moderate

CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES

2 of 2

Chlordiazepoxide, Clidinium Bromide also falls under CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES.

Theoretically, grapefruit juice might increase levels of drugs metabolized by CYP1A2.
In vitro research suggests that grapefruit juice might inhibit CYP1A2 enzymes. So far, this interaction has not been reported in humans.
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

Here's the gist with Librax (chlordiazepoxide plus clidinium) and grapefruit. The chlordiazepoxide part is a benzodiazepine, and grapefruit may slow down one of the enzymes (CYP1A2) that helps clear it. In theory, that could let the medicine build up a bit, which might mean more drowsiness, dizziness, or grogginess than usual.

The reassuring part: this concern comes only from lab studies, and it has never actually been reported in people. So I wouldn't lose sleep over an occasional grapefruit. Still, if you eat a lot of it or drink the juice daily, it's worth a quick chat with your pharmacist or doctor, especially if you already feel extra sleepy on this medication.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Unger M, Frank A. Simultaneous determination of the inhibitory potency of herbal extracts on the activity of six major cytochrome P450 enzymes using liquid chromatography/mass spectrometry and automated online extraction. Rapid Commun Mass Spectrom 2004;1 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

Grapefruit Also Interacts With Other Medications

Grapefruit has 775 major, 151 moderate, 63 minor known drug interactions in our database — the Chlordiazepoxide, Clidinium Bromide one above is among them. If you take anything else, check it against the full list below.

Major 775 Moderate 151 Minor 63 No known interaction 1,841 (incl. Chlordiazepoxide, Clidinium Bromide)
Taking anything else?

Check Another of Your Medications Against Grapefruit

Covers the 2,830 medications we’ve checked against Grapefruit. Pick one to open its full report.

From our Q&A

Questions About Grapefruit or Chlordiazepoxide, Clidinium Bromide

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Grapefruit or Chlordiazepoxide, Clidinium Bromide, 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 Chlordiazepoxide, Clidinium Bromide

This page covers Grapefruit only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Chlordiazepoxide, Clidinium Bromide page lists 188 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), Gamma-hydroxybutyrate (ghb) (major) and Henbane (major).

By severity: 10 major · 142 moderate · 36 minor.

From our pharmacist’s overview on the Chlordiazepoxide, Clidinium Bromide page

“Librax combines chlordiazepoxide, a benzodiazepine, with clidinium, an anticholinergic, and both halves interact with supplements, 188 ingredients in all. This is a list to approach with real care, starting with the 10 rated major.”

Reviewed by 2 · Jul 18, 2026

Open the Chlordiazepoxide, Clidinium Bromide interaction page

One more smart check

Taking Grapefruit as Part of a Dietary Supplement Product? Check It for Interactions

We hold 1,144 real supplement products containing Grapefruit, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Grapefruit. Your product may carry other ingredients that interact with Chlordiazepoxide, Clidinium Bromide too, on top of Grapefruit — and those would not show on this page. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Grapefruit and Chlordiazepoxide, Clidinium Bromide 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 Grapefruit
Top 10%

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

29 days ago today
Medication Chlordiazepoxide, Clidinium Bromide
Steady interest

#1,614 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 Grapefruit

What is Grapefruit?

Grapefruit
  • Source of vitamin C
  • Digestive complaints
  • Antimicrobial (seed extract)
  • Weight management
  • Skin and cosmetic uses

Grapefruit is a nutritious citrus fruit rich in vitamin C and other nutrients, and it is generally safe to eat. However, grapefruit is famous for serious interactions with many prescription medicines, so anyone taking medication should check with a pharmacist or doctor before consuming it regularly.

Read the full Grapefruit monograph & all interactions
Medication

About Chlordiazepoxide and Clidinium

What Is Chlordiazepoxide and Clidinium Used For?

Brand name: Librax

Chlordiazepoxide and clidinium capsules are used to help control both the physical and emotional factors involved in gastrointestinal (digestive) disorders. This includes use as add-on therapy for peptic ulcer, irritable bowel syndrome (also called irritable colon, spastic colon, or mucous colitis), and acute enterocolitis (sudden inflammation of the intestines).

Librax is one brand available in capsule form and is approved for the same set of gastrointestinal uses.

See full Chlordiazepoxide and Clidinium drug information
Keep checking

Other Drugs & Grapefruit

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

775Major
151Moderate
63Minor
1,840No known interaction
775 Major 151 Moderate 63 Minor 1,840 No interaction
Major

775 interactions

Showing 60 of 775 major interactions — see all 775 on the Grapefruit page.

Moderate

151 interactions

Showing 60 of 151 moderate interactions — see all 151 on the Grapefruit page.

Minor

63 interactions

Showing 60 of 63 minor interactions — see all 63 on the Grapefruit page.

No interaction 1,840 drugs checked — show the list

We also checked Grapefruit against these medications and found no known interaction in our sources. Open any page to confirm.

Showing the 60 most looked-up of 1,840 medications checked with no known interaction — see the full Grapefruit list.

See the full Grapefruit interactions page
See every supplement checked against Chlordiazepoxide, Clidinium Bromide, 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
Grapefruit monograph › Uses, safety, and every drug interaction in one place Chlordiazepoxide, Clidinium Bromide supplement interactions › Every supplement checked against Chlordiazepoxide, Clidinium Bromide, ranked by severity Chlordiazepoxide and Clidinium drug information › The full plain-English guide to this medication 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 Grapefruit and Chlordiazepoxide, Clidinium Bromide Together: Common Questions

Can you take Grapefruit with Chlordiazepoxide, Clidinium Bromide?
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.
Why are there 2 interactions listed for Grapefruit and Chlordiazepoxide, Clidinium Bromide?
Chlordiazepoxide, Clidinium Bromide belongs to more than one drug category, and Grapefruit interacts with each of those categories a little differently. We list every one so nothing is missed — your overall risk is driven by the most serious of them.
How serious is the Grapefruit and Chlordiazepoxide, Clidinium Bromide 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

Still Have a Question About Chlordiazepoxide, Clidinium Bromide and Grapefruit?

Our pharmacists answer your medication & supplement questions — free.

Ask a pharmacist

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.