Drug & supplement interaction

Grape + Bendamustine Hydrochloride

Bendamustine Hydrochloride brand name: Bendeka.

Moderate Interaction
The bottom line Moderate

Grape has a moderate interaction with Bendamustine Hydrochloride. Theoretically, grape juice might reduce the levels of CYP1A2 substrates.

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

Grape and Bendamustine Hydrochloride

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

Moderate

CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES

Why this applies to Bendamustine Hydrochloride

Bendamustine Hydrochloride falls under CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES — the group Grape interacts with.

Theoretically, grape juice might reduce the levels of CYP1A2 substrates.
A small pharmacokinetic study in healthy adults shows that ingestion of 200 mL of grape juice decreases phenacetin plasma levels. This is thought to be due to induction of CYP1A2.
Severity Moderate Likelihood Possible Evidence B

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 idea behind this pairing. Your body uses a liver enzyme called CYP1A2 to help process bendamustine (Bendeka), and grape juice may gently speed up that enzyme. If it clears the drug a bit faster, in theory you could get slightly less of bendamustine's cancer-fighting effect. I want to be honest, though: this is mostly theoretical and comes from a small study using a different drug, not bendamustine itself, so the real-world impact is uncertain.

One practical point worth knowing is that bendamustine is given as an infusion in a clinic, not a pill, so a single glass of juice is unlikely to make a big difference. Still, since this is a serious cancer medicine, please run any concentrated grape seed extract or supplement by your oncology team first.

References
  1. Xiao Dong S, Zhi Ping Z, Zhong Xiao W, et al. Possible enhancement of the first-pass metabolism of phenacetin by ingestion of grape juice in Chinese subjects. Br J Clin Pharmacol 1999;48:638-40. 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

Grape Also Interacts With Other Medications

Grape has 867 moderate, 42 minor known drug interactions in our database — the Bendamustine Hydrochloride 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 Grape

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

From our Q&A

Questions About Grape or Bendamustine Hydrochloride

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Grape or Bendamustine Hydrochloride, 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 Bendamustine Hydrochloride

This page covers Grape only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Bendamustine Hydrochloride page lists 86 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Acerola (moderate), Adrafinil (moderate), African Wild Potato (moderate), Alpha-lipoic Acid (moderate) and Ashitaba (moderate).

By severity: 62 moderate · 24 minor.

From our pharmacist’s overview on the Bendamustine Hydrochloride page

“Bendamustine (Bendeka), a chemotherapy used for certain leukemias and lymphomas, carries 86 supplement and herbal interactions on file, and none of them rates major, so this is a watch-and-adjust list rather than an alarm. Nearly all of the entries, about 80, involve the same liver enzyme, CYP1A2, which helps process bendamustine.”

Reviewed by 2 · Jul 18, 2026

Open the Bendamustine Hydrochloride interaction page

One more smart check

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

We hold 8,053 real supplement products containing Grape, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Grape. Your product may carry other ingredients that interact with Bendamustine Hydrochloride too, on top of Grape — 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 Grape and Bendamustine Hydrochloride 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 Grape
Top 5%

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

29 days ago today
Medication Bendamustine Hydrochloride
Top 25%

#380 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 Grape

What is Grape?

Grape
  • Antioxidant support
  • Heart and circulation health
  • Vein problems (such as varicose veins)
  • Eye health
  • General anti-inflammatory support

Grapes and grape products like grape seed extract contain antioxidant compounds such as resveratrol and proanthocyanidins that may support heart and blood vessel health. While the food is healthy and generally safe, the supplement evidence for treating specific conditions is mostly limited or preliminary. Talk with your pharmacist or doctor before starting a grape supplement.

Read the full Grape monograph & all interactions
Medication

About Bendamustine Injection

What Is Bendamustine Injection Used For?

Brand name: Bendeka

Bendamustine hydrochloride injection is used to treat adults with chronic lymphocytic leukemia (CLL). It is also used for adults with indolent B-cell non-Hodgkin lymphoma (NHL) — a slow-growing type of blood cancer — when the disease has continued to progress during or within six months of treatment with rituximab or a rituximab-containing regimen.

For CLL, how well bendamustine works compared to other first-line treatments (aside from chlorambucil) has not been fully established.

See full Bendamustine Injection drug information
Keep checking

Other Drugs & Grape

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

0Major
867Moderate
42Minor
1,920No known interaction
Moderate

867 interactions

Showing 60 of 867 moderate interactions — see all 867 on the Grape page.

Minor

42 interactions

No interaction 1,920 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 Grape and Bendamustine Hydrochloride Together: Common Questions

Can you take Grape with Bendamustine Hydrochloride?
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 Grape and Bendamustine Hydrochloride 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 Bendamustine Hydrochloride and Grape?

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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.