Drug & supplement interaction

Fever Bark + Metoclopramide Hydrochloride

Metoclopramide Hydrochloride brand name: Gimoti.

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

Fever Bark has a moderate interaction with Metoclopramide Hydrochloride. Theoretically, fever bark might increase the levels and clinical effects of CYP2D6 substrates.

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

Fever Bark and Metoclopramide Hydrochloride

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

Moderate

CYTOCHROME P450 2D6 (CYP2D6) SUBSTRATES

Why this applies to Metoclopramide Hydrochloride

Metoclopramide Hydrochloride falls under CYTOCHROME P450 2D6 (CYP2D6) SUBSTRATES — the group Fever Bark interacts with.

Theoretically, fever bark might increase the levels and clinical effects of CYP2D6 substrates.
In vitro research suggests that yohimbine, a constituent of fever bark, inhibits CYP2D6 enzyme activity. The effects of fever bark itself are unclear.
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: your body relies partly on an enzyme called CYP2D6 to clear metoclopramide. Fever bark contains a yohimbine-like compound that, at least in lab studies, can slow that same enzyme down. If that happens in real life, metoclopramide could linger longer and build up, meaning stronger effects.

Why that matters for this drug specifically: metoclopramide already carries a risk of restlessness, muscle stiffness, tremors, and other movement-related side effects, plus drowsiness. Higher levels could make those more likely. That said, this is only a theoretical concern from test-tube data, not proven in people, and the effect of fever bark itself is unclear. Still, I'd skip fever bark and check with your pharmacist or doctor first.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. VandenBrink, B. M., Foti, R. S., Rock, D. A., Wienkers, L. C., and Wahlstrom, J. L. Prediction of CYP2D6 drug interactions from in vitro data: evidence for substrate-dependent inhibition. Drug Metab Dispos. 2012;40(1):47-53. 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

Fever Bark Also Interacts With Other Medications

Fever Bark has 40 major, 673 moderate, 87 minor known drug interactions in our database — the Metoclopramide Hydrochloride one above is one of them. If you take anything else, check it against the full list below.

Major 40 Moderate 673 Minor 87 No known interaction 2,030 (incl. Metoclopramide Hydrochloride)
Taking anything else?

Check Another of Your Medications Against Fever Bark

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

Everything else you take

See Every Supplement That Interacts With Metoclopramide Hydrochloride

This page covers Fever Bark only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Metoclopramide Hydrochloride page lists 135 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: 1,4-butanediol (major), Beer (major), Gamma-hydroxybutyrate (ghb) (major), Kava (major) and L-tryptophan (major).

By severity: 7 major · 114 moderate · 14 minor.

From our pharmacist’s overview on the Metoclopramide Hydrochloride page

“Metoclopramide (Gimoti, also sold as Reglan) calms nausea and speeds a slow stomach by acting on the brain, and that is exactly where most of these 135 supplements and herbs collide with it. This is a list to treat with genuine care.”

Reviewed by 2 · Jul 18, 2026

Open the Metoclopramide Hydrochloride interaction page

How much people look this up

Where Fever Bark and Metoclopramide 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 Fever Bark
Steady interest

#1,204 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Metoclopramide Hydrochloride
Top half

#880 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 Fever Bark

What is Fever Bark?

Fever Bark
  • Fever
  • Diarrhea
  • Malaria (traditional)
  • Digestive complaints
  • Bitter tonic

Fever bark is the bark of the Australian tree Alstonia constricta, used in traditional medicine for fever, diarrhea, and infections. There is very little reliable human research to support these uses, and the bark contains potent alkaloids that may cause serious side effects. It is best avoided unless used under direct medical supervision.

Read the full Fever Bark monograph & all interactions
Medication

About Metoclopramide Nasal Spray

What Is Metoclopramide Nasal Spray Used For?

Brand name: Gimoti

Gimoti (metoclopramide nasal spray) is approved for adults with acute and recurrent diabetic gastroparesis — a condition where diabetes damages the nerves controlling stomach emptying, causing nausea, vomiting, and bloating. It works to relieve those symptoms by helping the stomach empty more normally.

Gimoti is not recommended for children, or for adults with moderate to severe kidney or liver disease. It is also not recommended for adults taking strong CYP2D6 inhibitor medications (certain antidepressants and other drugs that slow how the body breaks down metoclopramide).

See full Metoclopramide Nasal Spray drug information
Keep checking

Other Drugs & Fever Bark

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

40Major
673Moderate
87Minor
2,029No known interaction
40 Major 673 Moderate 87 Minor 2,029 No interaction
Major

40 interactions

Moderate

673 interactions

Showing 60 of 673 moderate interactions — see all 673 on the Fever Bark page.

Minor

87 interactions

Showing 60 of 87 minor interactions — see all 87 on the Fever Bark page.

No interaction 2,029 drugs checked — show the list

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

Showing the 60 most looked-up of 2,029 medications checked with no known interaction — see the full Fever Bark list.

See the full Fever Bark interactions page
See every supplement checked against Metoclopramide Hydrochloride, 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
Fever Bark monograph › Uses, safety, and every drug interaction in one place Metoclopramide Hydrochloride supplement interactions › Every supplement checked against Metoclopramide Hydrochloride, ranked by severity Metoclopramide Nasal Spray 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 Fever Bark and Metoclopramide Hydrochloride Together: Common Questions

Can you take Fever Bark with Metoclopramide 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 Fever Bark and Metoclopramide 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 Metoclopramide Hydrochloride and Fever Bark?

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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.