Drug & supplement interaction

Eucalyptus + Glipizide, Metformin

Glipizide, Metformin brand name: Metaglip.

Moderate Interaction
The bottom line Moderate

Glipizide, Metformin falls into 2 drug categories that Eucalyptus can interact with; the most serious is rated moderate. Theoretically, eucalyptus might increase the levels of CYP2C9 substrates.

Read the full interaction report
SeverityModerate
LikelihoodPossible
Interactions2
EvidenceD
What do Severity, Likelihood & Evidence mean?
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Interaction report

Eucalyptus and Glipizide, Metformin

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

Why Are There 2 Interactions?

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

Moderate

CYTOCHROME P450 2C9 (CYP2C9) SUBSTRATES

1 of 2

Why this applies to Glipizide, Metformin

Glipizide, Metformin falls under CYTOCHROME P450 2C9 (CYP2C9) SUBSTRATES — the group Eucalyptus interacts with.

Theoretically, eucalyptus might increase the levels of CYP2C9 substrates.
In vitro research suggests that eucalyptus oil might inhibit CYP2C9, although this 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

Your combo pill, Metaglip, pairs glipizide with metformin. The piece that matters here is glipizide, which your liver clears partly through an enzyme called CYP2C9. Lab studies hint that eucalyptus oil might slow that enzyme down. If that happened in a person, glipizide could build up a bit, and since glipizide already lowers blood sugar, that could mean a higher chance of low blood sugar (hypoglycemia), with signs like shakiness, sweating, dizziness, or feeling suddenly hungry or confused.

Here's my honest take: this is only seen in test-tube research, not in real people, so it's theoretical. Smelling eucalyptus in a vapor rub or lozenge is very unlikely to matter. Concentrated oil taken by mouth is a different story (and shouldn't be swallowed anyway). Check with your pharmacist before using eucalyptus products.

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
Moderate

ANTIDIABETES DRUGS

2 of 2

Glipizide, Metformin also falls under ANTIDIABETES DRUGS.

Theoretically, eucalyptus leaf might increase the risk of hypoglycemia.
Animal research suggests that eucalyptus leaf might have hypoglycemic activity, and might have additive effects when used with antidiabetes drugs.
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

Metaglip combines two diabetes medicines: glipizide, which nudges your body to release more insulin, and metformin, which lowers how much sugar your liver makes. Both work to bring your blood sugar down. The concern here is that eucalyptus leaf may also lower blood sugar a little, so stacking it on top of these medicines could push your levels too low.

Honestly, this is a theoretical worry based only on animal studies, so it isn't a strong or proven effect in people. Still, if you do use eucalyptus leaf supplements, keep an eye out for signs of low blood sugar like shakiness, sweating, dizziness, or feeling foggy. The vapor rubs and inhalants you smell aren't the concern. Check with your pharmacist before adding any eucalyptus product you'd swallow.

References
  1. Gray AM, Flatt PR. Antihyperglycemic actions of Eucalyptus globulus (Eucalyptus) are associated with pancreatic and extra-pancreatic effects in mice. J Nutr 1998;128:2319-23. 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

Eucalyptus Also Interacts With Other Medications

Eucalyptus has 877 moderate known drug interactions in our database — the Glipizide, Metformin one above is among them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Eucalyptus

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

Everything else you take

See Every Supplement That Interacts With Glipizide, Metformin

This page covers Eucalyptus only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Glipizide, Metformin page lists 307 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Siberian Cocklebur (major), Acai (moderate), Adrafinil (moderate) and African Wild Potato (moderate).

By severity: 2 major · 257 moderate · 48 minor.

From our pharmacist’s overview on the Glipizide, Metformin page

“Glipizide and metformin (Metaglip) already work hard to pull blood sugar down, which is exactly why this list of 307 ingredients deserves genuine vigilance rather than a shrug. Most of them, 239, can lower glucose on their own, and stacked on this pill the combined effect can tip into true hypoglycemia.”

Reviewed by 2 · Jul 18, 2026

Open the Glipizide, Metformin interaction page

One more smart check

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

We hold 216 real supplement products containing Eucalyptus, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Eucalyptus. Your product may carry other ingredients that interact with Glipizide, Metformin too, on top of Eucalyptus — 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 Eucalyptus and Glipizide, Metformin 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 Eucalyptus
Top half

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

29 days ago today
Medication Glipizide, Metformin
Steady interest

#1,610 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 Eucalyptus

What is Eucalyptus?

Eucalyptus
  • Cough and chest congestion
  • Colds and flu symptoms
  • Stuffy nose
  • Sore throat
  • Minor muscle and joint aches
  • Aromatherapy

Eucalyptus is best known for its strong-smelling oil used in vapor rubs, inhalants, and lozenges to ease coughs and congestion. It may provide mild, short-term relief of cold symptoms, but the oil is toxic if swallowed and must never be taken by mouth undiluted. Talk to a pharmacist or doctor before using it, especially in children, during pregnancy, or while breastfeeding.

Read the full Eucalyptus monograph & all interactions
Keep checking

Other Drugs & Eucalyptus

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

0Major
877Moderate
0Minor
1,952No known interaction
Moderate

877 interactions

Showing 60 of 877 moderate interactions — see all 877 on the Eucalyptus page.

No interaction 1,952 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 Eucalyptus and Glipizide, Metformin Together: Common Questions

Can you take Eucalyptus with Glipizide, Metformin?
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 2 interactions listed for Eucalyptus and Glipizide, Metformin?
Glipizide, Metformin belongs to more than one drug category, and Eucalyptus 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 Eucalyptus and Glipizide, Metformin 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

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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.