Drug & supplement interaction

Ginger + Diltiazem

Diltiazem brand names: Cardizem, Cardizem SR, Diltiaz SR, Cardizem CD, Tiazac, and others.

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

Diltiazem falls into 3 drug categories that Ginger can interact with; the most serious is rated moderate. Ginger might increase or decrease the levels of CYP3A4 substrates.

Read the full interaction report
SeverityModerate
LikelihoodPossible
Interactions3
EvidenceD
What do Severity, Likelihood & Evidence mean?
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Interaction report

Ginger and Diltiazem

These two interact in 3 distinct ways. Each one is explained separately below.

Why Are There 3 Interactions?

Ginger interacts with whole categories of medication. Diltiazem falls into 3 of those categories, so it can interact with Ginger in 3 different ways. We’ve listed each one below — your overall risk is driven by the most serious of them (Moderate).

Moderate

CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES

1 of 3

Why this applies to Diltiazem

Diltiazem falls under CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES — the group Ginger interacts with.

Ginger might increase or decrease the levels of CYP3A4 substrates.
In vitro research and some case reports suggest that ginger inhibits CYP3A4 activity. Three case reports from the World Health Organization (WHO) adverse drug reaction database describe increased toxicity in patients taking ginger and cancer medications that are CYP3A4 substrates (imatinib, dabrafenib, and crizotinib). However, the causality of this interaction is unclear due to the presence of multiple interacting drugs and routes of administration.
Conversely, other in vitro research suggests that ginger induces CYP3A4 activity, leading to reduced levels of CYP3A4 substrates. However, 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 short version: your body uses a liver enzyme called CYP3A4 to clear diltiazem, and ginger might nudge that enzyme one way or the other. If ginger slows the enzyme, a little more diltiazem could hang around, which might mean more dizziness, flushing, swelling in the ankles, or a slower heart rate and lower blood pressure. If ginger instead speeds the enzyme up, your diltiazem could work a bit less.

Now the reassuring part. This is based mostly on lab studies, with only a few unclear case reports involving other drugs, not diltiazem. Everyday culinary ginger is very unlikely to matter. If you're considering concentrated ginger supplements, just run it by your pharmacist or doctor first.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Haron MH, Dale O, Martin K, et al. Evaluation of the Herb-Drug Interaction Potential of Commonly Used Botanicals on the US Market with Regard to PXR- and AhR-Mediated Influences on CYP3A4 and CYP1A2. J Diet Suppl 2022. PubMed
  2. Husain I, Dale OR, Idrisi M, et al. Evaluation of the Herb-Drug Interaction (HDI) Potential of Zingiber officinale and Its Major Phytoconstituents. J Agric Food Chem. 2023;71(19):7521-7534.
  3. Pochet S, Lechon AS, Lescrainier C, et al. Herb-anticancer drug interactions in real life based on VigiBase, the WHO global database. Sci Rep 2022;12(1):14178. PubMed
Moderate

P-GLYCOPROTEIN SUBSTRATES

2 of 3

Diltiazem also falls under P-GLYCOPROTEIN SUBSTRATES.

Ginger might increase the absorption and blood levels of P-glycoprotein (P-gp) substrates.
In vitro research and case reports suggest that ginger inhibits drug efflux by P-gp, potentially increasing absorption and serum levels of P-gp substrates. Two case reports from the World Health Organization (WHO) adverse drug reaction database describe increased toxicity in patients taking ginger and cancer medications that are P-gp substrates (trametinib, crizotinib). However, the causality of this interaction is unclear due to the presence of multiple interacting drugs and routes of administration.
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 quick version: ginger may block a little pump in your gut called P-glycoprotein that normally limits how much of certain drugs gets absorbed. Diltiazem is one of those drugs, so in theory ginger could nudge its blood levels up a bit. If that happened, you might notice more of diltiazem's usual effects, like a slower heartbeat, dizziness, lightheadedness, lower blood pressure, or swelling in your ankles.

Now, take a breath. This concern comes mostly from lab studies and a couple of unclear case reports, not solid human data, so it's far from certain. Everyday cooking with ginger is very unlikely to matter. Concentrated ginger supplements are the bigger question mark. If you want to use them regularly, just run it by your pharmacist or doctor first.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Husain I, Dale OR, Idrisi M, et al. Evaluation of the Herb-Drug Interaction (HDI) Potential of Zingiber officinale and Its Major Phytoconstituents. J Agric Food Chem. 2023;71(19):7521-7534.
  2. Pochet S, Lechon AS, Lescrainier C, et al. Herb-anticancer drug interactions in real life based on VigiBase, the WHO global database. Sci Rep 2022;12(1):14178. PubMed
Minor

CALCIUM CHANNEL BLOCKERS

3 of 3

Diltiazem also falls under CALCIUM CHANNEL BLOCKERS.

Theoretically, taking ginger with calcium channel blockers might increase the risk of hypotension.
Some animal and in vitro research suggests that ginger has hypotensive and calcium channel-blocking effects. Another animal study shows that concomitant administration of ginger and the calcium channel blocker amlodipine leads to greater reductions in blood pressure when compared with amlodipine alone.
Severity Minor Likelihood Unlikely Evidence D

Interaction has been demonstrated in animal or in lab research but has been shown not to occur in humans..

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

Here's the gist: ginger may have a mild blood-pressure-lowering effect of its own, and some early animal and lab studies suggest it can act a little like a calcium channel blocker. Since diltiazem already relaxes your blood vessels to lower blood pressure and ease chest pain, pairing it with ginger could, in theory, nudge your blood pressure down a bit more than expected.

I want to be honest about how weak this is. We're talking about test-tube and animal data, not solid human studies, and it's rated minor and unlikely. The amount of ginger you'd use in cooking or tea is very unlikely to matter. With concentrated ginger supplements, just keep an eye out for dizziness, lightheadedness, or feeling faint when you stand up, and check with your pharmacist or doctor before starting them.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Ghayur MN, Gilani AH. Ginger lowers blood pressure through blockade of voltage-dependent calcium channels. J Cardiovasc Pharmacol 2005;45:74-80. PubMed
  2. Alam MA, Bin Jardan YA, Alzenaidy B, et al. Effect of Hibiscus sabdariffa and Zingiber officinale on pharmacokinetics and pharmacodynamics of amlodipine. J Pharm Pharmacol 2021;73(9):1151-60.

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

Ginger Also Interacts With Other Medications

Ginger has 874 moderate, 133 minor known drug interactions in our database — the Diltiazem one above is among them. If you take anything else, check it against the full list below.

Moderate 874 Minor 133 No known interaction 1,823 (incl. Diltiazem)
Taking anything else?

Check Another of Your Medications Against Ginger

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

From our Q&A

Questions About Ginger or Diltiazem

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

This page covers Ginger only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Diltiazem page lists 260 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), American Hellebore (major), American Mistletoe (major), Coleus (major) and Grapefruit (major).

By severity: 7 major · 214 moderate · 39 minor.

From our pharmacist’s overview on the Diltiazem page

“Someone on diltiazem (Cardizem, Tiazac) is usually managing blood pressure, angina, or a fast heart rhythm, so this list deserves genuine care. Seven of the 260 ingredients on file carry a major rating, and two of those are things people actually buy: grapefruit, which blocks the enzyme that clears diltiazem and can push its blood leve…”

Reviewed by 2 · Jul 18, 2026

Open the Diltiazem interaction page

One more smart check

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

We hold 9,640 real supplement products containing Ginger, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Ginger. Your product may carry other ingredients that interact with Diltiazem too, on top of Ginger — 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 Ginger and Diltiazem 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 Ginger
Top 5%

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

29 days ago today
Medication Diltiazem
Top 25%

#318 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 Ginger

What is Ginger?

Ginger
  • Nausea and vomiting
  • Motion sickness
  • Morning sickness in pregnancy
  • Digestive upset
  • Menstrual cramps
  • Joint pain and inflammation

Ginger is a widely used culinary spice with a long history in traditional medicine, and it has the strongest evidence for helping with nausea and vomiting, including from motion sickness, pregnancy, and chemotherapy. It is generally safe in food and supplement amounts for most people, though it may cause mild stomach upset. Talk with your pharmacist or doctor before using ginger supplements, especially if you are pregnant, have a bleeding disorder, or take other medicines.

Read the full Ginger monograph & all interactions
Medication

About Diltiazem

What Is Diltiazem Used For?

Brand names: Cardizem, Cardizem SR, Diltiaz SR, Cardizem CD, Tiazac, Diltiaz XT, Diltiaz CD, Dilacor, Diltiaz, Cardizem LA, Dilacor XR, Cartia XT, Tiamate, Adizem-SR, Adizem-XL, Angitil SR, Angitil XL, Calcicard CR, Dilcardia SR, Dilzem SR, Dilzem XL, Slozem, Tildiem LA, Tildiem Retard, Viazem XL, Zemtard 120XL, Zemtard 180XL, Zemtard 240XL, Zemtard 300XL

Oral extended-release diltiazem (capsules and tablets) treats high blood pressure (hypertension). It is also used for chronic stable angina, which is chest pain from the heart working harder than its blood supply allows. It can be used alone or with other blood pressure medicines.

Some extended-release capsule products, such as Cartia, Cartia Xt and certain generic diltiazem capsules, are also approved for angina due to coronary artery spasm. The intravenous (IV) injection is a different use: it gives temporary control of a rapid heart rate in atrial fibrillation or atrial flutter, and rapidly converts paroxysmal supraventricular tachycardia (PSVT) to normal rhythm.

See full Diltiazem drug information
Keep checking

Other Drugs & Ginger

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

0Major
874Moderate
133Minor
1,822No known interaction
874 Moderate 133 Minor 1,822 No interaction
Moderate

874 interactions

Showing 60 of 874 moderate interactions — see all 874 on the Ginger page.

Minor

133 interactions

Showing 60 of 133 minor interactions — see all 133 on the Ginger page.

No interaction 1,822 drugs checked — show the list

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

Showing the 60 most looked-up of 1,822 medications checked with no known interaction — see the full Ginger list.

See the full Ginger interactions page
See every supplement checked against Diltiazem, 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
Ginger monograph › Uses, safety, and every drug interaction in one place Diltiazem supplement interactions › Every supplement checked against Diltiazem, ranked by severity Diltiazem 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 Ginger and Diltiazem Together: Common Questions

Can you take Ginger with Diltiazem?
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.
Why are there 3 interactions listed for Ginger and Diltiazem?
Diltiazem belongs to more than one drug category, and Ginger 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 Ginger and Diltiazem 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 Diltiazem and Ginger?

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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.