Drug & supplement interaction

Quassia + Esomeprazole Strontium

Esomeprazole Strontium brand name: Esomeprazole Strontium.

Minor Interaction
The bottom line Minor

Quassia has a minor interaction with Esomeprazole Strontium. Theoretically, due to reports that quassia increases stomach acid, quassia might decrease the effectiveness of PPIs.

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

Quassia and Esomeprazole Strontium

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

Minor

PROTON PUMP INHIBITORS (PPIs)

Why this applies to Esomeprazole Strontium

Esomeprazole Strontium falls under PROTON PUMP INHIBITORS (PPIs) — the group Quassia interacts with.

Theoretically, due to reports that quassia increases stomach acid, quassia might decrease the effectiveness of PPIs. PPIs include omeprazole (Prilosec), lansoprazole (Prevacid), rabeprazole (Aciphex), pantoprazole (Protonix), and esomeprazole (Nexium).
Severity Minor 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 quassia and your esomeprazole (the strontium version works just like the more familiar Nexium). Esomeprazole is a proton pump inhibitor, meaning it lowers the amount of acid your stomach makes. Quassia is a bitter herb, and bitters can actually nudge your stomach to produce more digestive juices and acid. So in theory, taking the two together could work against each other and make your esomeprazole feel a little less effective, perhaps with more heartburn or reflux sneaking back.

That said, this is very weak, theory-based evidence, not something proven in real patients. It's rated minor. If you enjoy a quassia bitter and notice your reflux acting up, that's worth a quick chat with your pharmacist or doctor before changing anything.

References
  1. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.

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

Quassia Also Interacts With Other Medications

Quassia has 162 moderate, 35 minor known drug interactions in our database — the Esomeprazole Strontium 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 Quassia

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

Everything else you take

See Every Supplement That Interacts With Esomeprazole Strontium

This page covers Quassia only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Esomeprazole Strontium page lists 154 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Grapefruit (major), St. John's Wort (major), Acacia Rigidula (moderate) and Adrafinil (moderate).

By severity: 3 major · 102 moderate · 49 minor.

From our pharmacist’s overview on the Esomeprazole Strontium page

“People managing reflux or ulcers with esomeprazole strontium, a proton pump inhibitor, are often the same people reaching for herbal remedies and fiber, and this list of 154 interacting ingredients deserves a careful read, not a shrug. Three entries rate major, and all three, grapefruit, St.”

Reviewed by 2 · Jul 18, 2026

Open the Esomeprazole Strontium interaction page

One more smart check

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

We hold 172 real supplement products containing Quassia, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Quassia. Your product may carry other ingredients that interact with Esomeprazole Strontium too, on top of Quassia — 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 Quassia and Esomeprazole Strontium 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 Quassia
Top half

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

29 days ago today
Medication Esomeprazole Strontium
Top half

#1,059 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 Quassia

What is Quassia?

  • Loss of appetite
  • Digestive upset
  • Head lice (topical)
  • Intestinal worms/parasites
  • Bitter tonic

Quassia is a tropical wood known for its very bitter taste, traditionally used as a digestive bitter and as a folk remedy for parasites and head lice. Human evidence for these uses is limited, and high doses may irritate the stomach, so it should be used cautiously and avoided in pregnancy.

Read the full Quassia monograph & all interactions
Keep checking

Other Drugs & Quassia

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

0Major
162Moderate
35Minor
2,632No known interaction
Moderate

162 interactions

Showing 60 of 162 moderate interactions — see all 162 on the Quassia page.

Minor

35 interactions

No interaction 2,632 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 Quassia and Esomeprazole Strontium Together: Common Questions

Can you take Quassia with Esomeprazole Strontium?
There is only a minor interaction, which is usually not serious. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the Quassia and Esomeprazole Strontium interaction?
We rate it Minor. This interaction is generally not clinically significant, but it remains worth noting and discussing with your 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.