Drug & supplement interaction

Eucalyptus + Granisetron

Granisetron brand names: Kytril, Sustol.

No Known Interaction
Medically reviewed by · Updated July 2026 · Pair last verified Sep 20, 2026
The bottom line No known interaction

We found no known interaction between Eucalyptus and Granisetron in our sources. Absence of a documented interaction is not the same as proven safety, and does not guarantee one does not exist. Do not start, stop, or change a medication or supplement based on this page; confirm with your pharmacist or doctor first. Additionally, although there is no interaction, the label for Granisetron states a food rule worth keeping to, and the two are separately associated with some of the same side effects, which would make a new symptom harder to attribute to one or the other.

Know someone taking this? Share
Facebook Post Reddit Email
On this page
Interaction report

Eucalyptus and Granisetron

We checked these two against our interaction database. Here is what we found.

No Known Interaction Found

We did not find a documented interaction between Granisetron and Eucalyptus in our sources. This does not guarantee that the combination is completely free of risk — there is often limited research on supplements and herbal products, especially around drug interactions.

If you decide to take both, the practical routine is simple: add one new thing at a time and note the date you started it. If the combination is going to disagree with you, it usually shows in the first days to a couple of weeks — and a start date turns “I’ve been feeling off” into something a pharmacist can actually work with. Do not stop a prescribed medicine on your own.

Always talk with your pharmacist or doctor before making changes to your medications or supplements, particularly if you take several medications or have an ongoing health condition.

Eucalyptus safety at a glance

Eucalyptus overall Use caution Generally safe in small amounts for inhalation or diluted topical use, but the undiluted oil can be poisonous if swallowed.
Pregnancy Likely Safe When used orally in amounts commonly found in foods. There is insufficient reliable information available about the safety of medicinal amounts of eucalyptus oi... Read the full pregnancy detail
Breastfeeding Likely Safe When used orally in amounts commonly found in foods. There is insufficient reliable information available about the safety of medicinal amounts of eucalyptus oi... Read the full breastfeeding detail

Pregnancy & breastfeeding ratings are from Natural Medicines (Therapeutic Research Center) — the full detail is in the Special populations card below. Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Granisetron and Eucalyptus? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Granisetron

Interactions in our licensed database are recorded against drug classes, not just single drug names. Granisetron is filed under 3 classifications — serotonergic drugs, serotonergic drugs, oral drugs. Eucalyptus has documented interactions with 7 drug classes — the most serious being amphetamines (moderate), antidiabetes drugs (moderate) and cytochrome p450 1a2 (cyp1a2) substrates (moderate) — and none of Granisetron’s classifications are among them.

Classification data comes from our licensed Natural Medicines dataset. A medication can belong to classes beyond those recorded there, so this describes how the check was run — it is not a safety guarantee.

Keep it in perspective

Eucalyptus Does Interact With Other Medications

Eucalyptus has 878 moderate known drug interactions in our database — Granisetron isn’t one of them. If you take anything else, check it against the full list below.

Moderate 878 No known interaction 1,952 (incl. Granisetron)
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.

What to actually watch for

No Interaction Found — But Data Suggests Eucalyptus and Granisetron May Share Several of the Same Side Effects

This is not an interaction. Neither one changes how your body handles the other, and nothing here says they react together. What our sources do show is that each has separately been linked to the effects below — so taking both can make those effects more likely to turn up, and harder to pin on one or the other if they do.

  • A fast or pounding heartbeat / Drowsiness / Anxiety or restlessness Additional detail

    Eucalyptus

    “Orally, diluted eucalyptus oil is generally well tolerated, but the undiluted oil can cause toxicity.

    Most Common Adverse Effects:

    Orally: Diarrhea, nausea, vomiting.

    Topically: Burning, itching, redness, stinging.

    Serious Adverse Effects (Rare):

    Orally: Signs of toxicity can occur with the undiluted oil at doses as low as 1 mL and include central nervous system depression, shallow respiration, rapid pulse, apnea, co…”

    Eucalyptus · Natural Medicines adverse-effect record, reported in depression.

    Granisetron

    Listed in the ADVERSE REACTIONS section of the FDA label for Granisetron. Read the label on DailyMed ›

  • Fever / Headache Additional detail

    Eucalyptus

    “Orally, eucalyptus oil can cause central nervous system depression, coma, and status epilepticus.

    Topically, orally, and by inhalation, eucalyptus oil has been associated with seizures. A systematic review describes the characteristics of 49 children and 61 adults with seizures associated with various routes of administration.”

    Eucalyptus · Natural Medicines adverse-effect record, reported in cluster headache.

    6 sources cited
    1. 12867. De Vincenzi M, Silano M, De Vincenzi A, et al. Constituents of aromatic plants: eucalyptol. Fitoterapia 2002;73:269-75. PubMed
    2. 48946. Tascini, C., Ferranti, S., Gemignani, G., Messina, F., and Menichetti, F. Clinical microbiological case: fever and headache in a heavy consumer of eucalyptus extract. Clin Microbiol.Infect. 2002;8(7):437, 445-437, 446. PubMed
    3. 48983. Spoerke, D. G., Vandenberg, S. A., Smolinske, S. C., Kulig, K., and Rumack, B. H. Eucalyptus oil: 14 cases of exposure. Vet Hum.Toxicol 1989;31(2):166-168.
    4. 107494. Panda PK, Sharawat IK, Panda P, Dawman L, Kasinathan A. Clinico-laboratory characteristics and outcome of patients with eucalyptus oil-induced/provoked seizures: A case series and systematic review of the published patients. Trop Doct 2021;51(4):518-522. PubMed
    5. 105028. Mathew T, John SK, Kamath V, et al. Essential oil related seizures (EORS): A multi-center prospective study on essential oils and seizures in adults. Epilepsy Res. 2021;173:106626. PubMed
    6. 107493. Dudipala SC, Mandapuram P, Ch LK. Eucalyptus Oil-Induced Seizures in Children: Case Reports and Review of the Literature. J Neurosci Rural Pract 2021;12(1):112-115. PubMed

    Granisetron

    Listed in the ADVERSE REACTIONS section of the FDA label for Granisetron. Read the label on DailyMed ›

  • Stomach pain Additional detail

    Eucalyptus

    “Orally, eucalyptus oil can cause nausea, vomiting, and diarrhea. Abdominal pain has been reported in a trial of the eucalyptus constituent eucalyptol for inflammatory bowel disease (IBD).”

    Eucalyptus · Natural Medicines adverse-effect record, reported in crohn disease.

    4 sources cited
    1. 48983. Spoerke, D. G., Vandenberg, S. A., Smolinske, S. C., Kulig, K., and Rumack, B. H. Eucalyptus oil: 14 cases of exposure. Vet Hum.Toxicol 1989;31(2):166-168.
    2. 48993. Tibballs, J. Clinical effects and management of eucalyptus oil ingestion in infants and young children. Med J Aust 8-21-1995;163(4):177-180. PubMed
    3. 48995. Webb, N. J. and Pitt, W. R. Eucalyptus oil poisoning in childhood: 41 cases in south-east Queensland. J Paediatr.Child Health 1993;29(5):368-371. PubMed
    4. 48936. Juergens, U. R. [Reducing the need for cortisone. Does eucalyptus oil work in asthma? (interview by Brigitte Moreano]. MMW.Fortschr Med 3-29-2001;143(13):14.

    Granisetron

    Listed in the ADVERSE REACTIONS section of the FDA label for Granisetron. Read the label on DailyMed ›

  • Diarrhea / Vomiting / Nausea Additional detail

    Eucalyptus

    Recorded for Eucalyptus in the same Natural Medicines adverse-effect record shown under A fast or pounding heartbeat / Drowsiness / Anxiety or restlessness above.

    Granisetron

    Listed in the ADVERSE REACTIONS section of the FDA label for Granisetron. Read the label on DailyMed ›

Reported for Eucalyptus but not commonly for Granisetron: seizures, muscle weakness, sore throat and a skin rash.

Effects for Granisetron come from the ADVERSE REACTIONS section of its FDA label; effects for Eucalyptus come from the Natural Medicines adverse-effect record, quoted above. Wording is matched across sources by our own clinical vocabulary, so treat this as a prompt to pay attention, not a diagnosis.

Special populations

Eucalyptus in Pregnancy & Breastfeeding

Pregnancy And Lactation Likely Safe

When used orally in amounts commonly found in foods. There is insufficient reliable information available about the safety of medicinal amounts of eucalyptus oil; avoid using.

DISCLAIMER: This tool is intended for informational purposes only, and should not be interpreted as specific medical advice. Patients should consult with a qualified healthcare provider before making decisions about therapies and/or health conditions.© 2026 Therapeutic Research Center

How to take them

Some Granisetron Products Have a Food Rule — Eucalyptus Should Not Break It

At least one FDA label for a product containing Granisetron says to take it on an empty stomach. Most supplements — Eucalyptus included — are taken with a meal, so the easy mistake is swallowing both together at breakfast. Where that rule applies, keep Granisetron on its own and move Eucalyptus to a meal later in the day.

This may not be true of your version. Food instructions belong to the product, not the ingredient: two Granisetron products can carry different directions, and extended-release forms often differ from immediate-release ones. The label we read is quoted below — check the directions on your own box or bottle, or ask your pharmacist, for how to take the exact product you were given.

Recommended Dosage ( 2.2 ): The recommended dosage in adults is 10 mg administered as a single subcutaneous injection at least 30 minutes before the start of emetogenic chemotherapy on Day 1.

From the Dosage and Administration section of the FDA label we read for Granisetron — where that label names a specific product, the instruction is that product's. Read the label on DailyMed ›

A food rule is not an interaction — it is about how much of the medicine you absorb. The directions that came with your own product, and your pharmacist, outrank anything on this page.

Overlapping uses

What Granisetron Is Prescribed For, and What Eucalyptus Has Been Studied For

These two come up together because they touch the same health topic — not because they do the same job. Granisetron is a prescription medicine with approved uses on its FDA label. Eucalyptus is a supplement: what follows is what researchers have looked at it for, and how strong that evidence is.

Granisetron is prescribed for: Granisetron is used to prevent nausea and vomiting linked to emetogenic (nausea-causing) cancer chemotherapy — including high-dose cisplatin — and radiation therapy, including total body irradiation and fractionated abdominal radiation. Granisetron hydrochloride tablets and Granisol oral solution are approved for both the chemotherapy and radiation indications. Sancuso skin patch is approved for prevention of nausea and vomiting in adults receiving moderately and/or highly emetogenic chemotherapy regimens of up to 5 consecutive days. Granisetron hydrochloride injection (intravenous) is also used to prevent and treat postoperative nausea and vomiting in adults.

Read the rest of what Granisetron is prescribed for

Sustol (subcutaneous injection) is used in combination with other anti-nausea medicines in adults specifically for the prevention of acute and delayed nausea and vomiting associated with moderately emetogenic chemotherapy or anthracycline and cyclophosphamide combination chemotherapy regimens.

Eucalyptus has been studied for:

  • Cancer studied, not established Eucalyptus has been studied for this. Natural Medicines rates the evidence: Insufficient Reliable Evidence To Rate Read what the research shows

    Eucalyptus for cancer

    Although there is interest in using oral eucalyptus for cancer, there is insufficient reliable information about the clinical effects of eucalyptus for this condition.

Effectiveness ratings and the research summaries above are the verbatim record from the Natural Medicines database, which grades evidence from “Effective” down to “Insufficient Reliable Evidence To Rate”. A rating below the top of that scale means researchers have looked at it — not that it works, and never that it can stand in for a prescribed medicine. Do not stop or replace Granisetron on your own; if you are taking Eucalyptus for the same health topic, tell your prescriber, especially if the medicine is being adjusted to a target.

Everything else you take

See Every Supplement That Interacts With Granisetron

This page covers Eucalyptus only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Granisetron page lists 38 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Lithium (major), 5-htp (moderate), Acetyl-l-carnitine (moderate) and Ayahuasca (moderate).

By severity: 2 major · 25 moderate · 11 minor.

From our pharmacist’s overview on the Granisetron page

“Granisetron (Kytril, Sustol) blocks serotonin signals to stop nausea from chemotherapy and surgery, and this is a list that warrants real caution before you add a supplement to it. Most of the entries raise serotonin themselves, and stacking them on a serotonin-acting drug can push toward serotonin syndrome, a dangerous overload of tha…”

Reviewed by 2 · Jul 18, 2026

Open the Granisetron 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. Even though Eucalyptus itself has no known interaction with Granisetron, another ingredient on your label might. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Eucalyptus and Granisetron 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

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

29 days ago today
Medication Granisetron
Steady interest

#2,261 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.

Where does our data come from?
  • Source: the Natural Medicines (TRC Healthcare) clinical database — the evidence-graded professional reference for herb & supplement interactions.
  • Citation library: 103,510 references behind our interaction content, 65,311 of them resolved to verified PubMed/DOI sources. See every Eucalyptus reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 20, 2026. The Eucalyptus and Granisetron records this page draws on were last updated July 10, 2026.
  • What “no known interaction” means: no documented interaction in the sources above — not a guarantee of safety. Supplements are studied far less than prescription drugs, so we say exactly what the evidence supports, and nothing more.
Data structure & sourcing designed and verified by .
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.

Eucalyptus globulus · Myrtaceae · Leaves and essential oil · Essential oil, inhalants/vapor rubs, lozenges, tea, capsules, topical creams

An interaction check asks whether these two react with each other — it does not ask whether Eucalyptus is a good idea for someone in your situation. Here is what our Eucalyptus record says about it on its own.

Eucalyptus: dosing

There is no official standardized dose for eucalyptus. The right amount depends on the product and how it is used, such as a vapor rub, lozenge, inhalant, or tea.The safest approach is to follow the directions on the product label and not exceed them. Never swallow the concentrated essential oil, and always dilute it before putting it on the skin.

From our Eucalyptus monograph — the full record covers uses, side effects and every documented interaction.

Read the full Eucalyptus monograph & all interactions
Medication

About Granisetron

What Is Granisetron Used For?

Brand names: Kytril, Sustol

Granisetron is used to prevent nausea and vomiting linked to emetogenic (nausea-causing) cancer chemotherapy — including high-dose cisplatin — and radiation therapy, including total body irradiation and fractionated abdominal radiation. Granisetron hydrochloride tablets and Granisol oral solution are approved for both the chemotherapy and radiation indications. Sancuso skin patch is approved for prevention of nausea and vomiting in adults receiving moderately and/or highly emetogenic chemotherapy regimens of up to 5 consecutive days.

Granisetron hydrochloride injection (intravenous) is also used to prevent and treat postoperative nausea and vomiting in adults. Sustol (subcutaneous injection) is used in combination with other anti-nausea medicines in adults specifically for the prevention of acute and delayed nausea and vomiting associated with moderately emetogenic chemotherapy or anthracycline and cyclophosphamide combination chemotherapy regimens.

See full Granisetron drug information
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
878Moderate
0Minor
1,951No known interaction
878 Moderate 1,951 No interaction
Moderate

878 interactions

Showing 60 of 878 moderate interactions — see all 878 on the Eucalyptus page.

No interaction 1,951 drugs checked — show the list

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

Showing the 60 most looked-up of 1,951 medications checked with no known interaction — see the full Eucalyptus list.

See the full Eucalyptus interactions page
See every supplement checked against Granisetron, ranked by severity
Evidence & sources

Eucalyptus References

The 23 references that drive our Eucalyptus monograph and interaction data, from the evidence-graded Natural Medicines (TRC Healthcare) database. Citations with a link open the study on PubMed or the publisher’s site.

  1. Electronic Code of Federal Regulations. Title 21. Part 182 -- Substances Generally Recognized As Safe. Available at: https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?CFRPart=182
  2. 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
  3. De Vincenzi M, Silano M, De Vincenzi A, et al. Constituents of aromatic plants: eucalyptol. Fitoterapia 2002;73:269-75. PubMed
  4. 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
  5. Whitman BW, Ghazizadeh H. Eucalyptus oil: therapeutic and toxic aspects of pharmacology in humans and animals. J Paediatr Child Health 1994;30:190-1. PubMed
  6. Barker SC and Altman PM. An ex vivo, assessor blind, randomised, parallel group, comparative efficacy trial of the ovicidal activity of three pediculicides after a single application--melaleuca oil and lavender oil, eucalyptus oil and lemon tea tree oil,
  7. Vilaplana, J. and Romaguera, C. Allergic contact dermatitis due to eucalyptol in an anti-inflammatory cream. Contact Dermatitis 2000;43(2):118.
  8. Juergens, U. R. [Reducing the need for cortisone. Does eucalyptus oil work in asthma? (interview by Brigitte Moreano]. MMW.Fortschr Med 3-29-2001;143(13):14.
  9. Tascini, C., Ferranti, S., Gemignani, G., Messina, F., and Menichetti, F. Clinical microbiological case: fever and headache in a heavy consumer of eucalyptus extract. Clin Microbiol.Infect. 2002;8(7):437, 445-437, 446. PubMed
  10. Galdi, E., Perfetti, L., Calcagno, G., Marcotulli, M. C., and Moscato, G. Exacerbation of asthma related to Eucalyptus pollens and to herb infusion containing Eucalyptus. Monaldi Arch.Chest Dis. 2003;59(3):220-221.
  11. Spoerke, D. G., Vandenberg, S. A., Smolinske, S. C., Kulig, K., and Rumack, B. H. Eucalyptus oil: 14 cases of exposure. Vet Hum.Toxicol 1989;31(2):166-168.
  12. Jori, A., Bianchetti, A., Prestini, P. E., and Gerattini, S. Effect of eucalyptol (1,8-cineole) on the metabolism of other drugs in rats and in man. Eur.J Pharmacol 1970;9(3):362-366. PubMed
  13. Tibballs, J. Clinical effects and management of eucalyptus oil ingestion in infants and young children. Med J Aust 8-21-1995;163(4):177-180. PubMed
  14. Webb, N. J. and Pitt, W. R. Eucalyptus oil poisoning in childhood: 41 cases in south-east Queensland. J Paediatr.Child Health 1993;29(5):368-371. PubMed
  15. Gyldenløve M, Menné T, Thyssen JP. Eucalyptus contact allergy. Contact Dermatitis. 2014;71(5):303-304. PubMed

Medication overviews come from MedlinePlus (NIH); supplement label data from the NIH Dietary Supplement Label Database. Content is written and reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.

Pharmacist Counseling Corner

Taking Eucalyptus and Granisetron Together: Common Questions

Is it safe to take Eucalyptus with Granisetron?
We do not list a known interaction between Eucalyptus and Granisetron. That does not guarantee the combination is risk-free, so confirm with your pharmacist or doctor — especially if you take other medications or have a health condition.
Do Eucalyptus and Granisetron have any of the same side effects?
Yes — our sources link each of them separately to 9 of the same effects. That is not an interaction: neither changes how your body handles the other. It does mean that if one of those effects turns up, it can be harder to tell which one is behind it. They are listed on this page with the source behind each.
Should I take Eucalyptus and Granisetron at the same time of day?
At least one FDA label for a product containing Granisetron says to take it on an empty stomach, and supplements are usually taken with a meal — so taking them together at breakfast is the easy mistake. Where that applies, keep Granisetron on its own and move Eucalyptus to a meal later in the day. Food instructions belong to the product rather than the ingredient, so check the directions on your own box. This is about absorption, not an interaction.
Are Eucalyptus and Granisetron used for the same thing?
They overlap in purpose, which usually means the real question is whether you need both rather than whether they are safe together. This page lists the shared uses and how strong the evidence is for Eucalyptus in each. That is a conversation for your prescriber, especially if Granisetron is being adjusted to a target.
How was the Eucalyptus and Granisetron combination checked?
Interactions in our licensed database are recorded against drug classes. Granisetron is filed under 3 classifications, and Eucalyptus has documented interactions with 7 drug classes — none of Granisetron's classifications are among them. A medication can belong to classes beyond those recorded in our dataset, so this describes how the check was run rather than guaranteeing safety.
Does Eucalyptus interact with any other medications?
Yes. Eucalyptus has 878 documented drug interactions in our database — Granisetron is simply not one of them. If you take anything else, it is worth checking each one; they are all listed on this page.
Does Granisetron interact with any supplements?
Yes. Granisetron has documented interactions with 38 supplements in our database — Eucalyptus is not one of them. The Granisetron interaction page linked on this page lists every one, ranked by severity.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

Where next

Keep Exploring

Eucalyptus monograph Uses, safety profile, and every drug interaction in one place Granisetron drug information The full plain-English guide to this medication Granisetron supplement interactions Every supplement checked against Granisetron, ranked by severity Supplement interaction checker Check any supplement or product against your medications Browse medications A–Z Every drug we’ve checked against herbs & supplements References The 23 citations behind this page Ask a pharmacist Free, personal answer from our licensed team

Still Have a Question About Granisetron and Eucalyptus?

Our pharmacists answer your medication & supplement questions — free.

Ask a pharmacist

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.