Eucalyptus + Belladonna, Caffeine, Ergotamine, Pentobarbital
Belladonna, Caffeine, Ergotamine, Pentobarbital brand name: Micomp PB.
Belladonna, Caffeine, Ergotamine, Pentobarbital falls into 3 drug categories that Eucalyptus can interact with; the most serious is rated moderate. Theoretically, eucalyptus might increase the levels of CYP1A2 substrates.
Read the full interaction reportEucalyptus and Belladonna, Caffeine, Ergotamine, Pentobarbital
These two interact in 3 distinct ways. Each one is explained separately below.
Why Are There 3 Interactions?
Eucalyptus interacts with whole categories of medication. Belladonna, Caffeine, Ergotamine, Pentobarbital falls into 3 of those categories, so it can interact with Eucalyptus in 3 different ways. We’ve listed each one below — your overall risk is driven by the most serious of them (Moderate).
CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES
1 of 3Why this applies to Belladonna, Caffeine, Ergotamine, Pentobarbital
Belladonna, Caffeine, Ergotamine, Pentobarbital falls under CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES — the group Eucalyptus interacts with.
In vitro research suggests that eucalyptus oil might inhibit CYP1A2, although this has not been reported in humans.
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.
This combination product (Micomp PB) contains caffeine, and caffeine is cleared by a liver enzyme called CYP1A2. In lab dish studies, eucalyptus oil appeared to slow that enzyme down a bit. If that happened in real life, caffeine could hang around longer than usual, which might mean a touch more jitteriness, a racing heartbeat, trouble sleeping, or feeling wired.
The important part: this is only seen in test tubes and animals, not in people. Breathing in eucalyptus from a vapor rub or lozenge is very unlikely to change how your medicine works. Just don't swallow eucalyptus oil, since it's toxic by mouth. If you use concentrated eucalyptus products regularly, mention it to your pharmacist or doctor so they can keep an eye on things.
- 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
CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES
2 of 3Belladonna, Caffeine, Ergotamine, Pentobarbital also falls under CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES.
In vitro research suggests that eucalyptus oil might inhibit CYP3A4, although this has not been reported in humans.
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.
This combination pill (Micomp PB) contains ergotamine, which your liver clears using an enzyme called CYP3A4. Lab and test-tube studies hint that eucalyptus oil could slow that same enzyme down. If that happened in the body, ergotamine might build up a bit, which could bring on stronger side effects like nausea, cold or tingling fingers and toes, leg cramps, or a faster heartbeat from the caffeine.
Here's the reassuring part: this has only been seen in lab dishes, never in real people, so it's mostly theoretical. Breathing in eucalyptus vapor or using a chest rub is unlikely to cause trouble. Still, since ergotamine can be sensitive to changes, check with your pharmacist or doctor before swallowing concentrated eucalyptus products.
- 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
PENTOBARBITAL (Nembutal)
3 of 3Animal research suggests that inhaling eucalyptol reduces the level of pentobarbital that reaches the brain.
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.
Your combination product (Micomp PB) contains a small dose of pentobarbital, a barbiturate that calms the nervous system. The only signal we have here involves that ingredient. In animal studies, breathing in eucalyptol (the active compound in eucalyptus oil) seemed to lower how much pentobarbital reached the brain, which could mean a slightly weaker calming or sleep-promoting effect. This is theoretical and based only on lab work, so I wouldn't lose sleep over it.
Practically, smelling a vapor rub or inhalant is very unlikely to undo your medicine. Never swallow eucalyptus oil since it's toxic by mouth. If you notice your medication isn't working as well, please check with your pharmacist or doctor before changing anything.
- 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
What These Ratings Mean
Every interaction above is graded three ways — here’s the key to each label.
Clinically significant. Avoid the combination, or use only under close professional supervision.
Usually worth avoiding or managing — may need monitoring, a dose change, or timing apart.
Generally not serious. Be aware of it and mention it to your pharmacist.
- 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.
- 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.
Eucalyptus Also Interacts With Other Medications
Eucalyptus has 877 moderate known drug interactions in our database — the Belladonna, Caffeine, Ergotamine, Pentobarbital one above is among them. If you take anything else, check it against the full list below.
Check Another of Your Medications Against Eucalyptus
We haven’t checked that one against Eucalyptus yet — ask our pharmacists directly.
Covers the 2,830 medications we’ve checked against Eucalyptus. Pick one to open its full report.
See Every Supplement That Interacts With Belladonna, Caffeine, Ergotamine, Pentobarbital
This page covers Eucalyptus only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Belladonna, Caffeine, Ergotamine, Pentobarbital page lists 290 supplements it has a documented interaction with, worst first, each one explained.
The most serious there right now: 1,4-butanediol (major), Activated Charcoal (major), Beer (major), Ephedra (major) and Gamma-hydroxybutyrate (ghb) (major).
By severity: 15 major · 227 moderate · 48 minor.
From our pharmacist’s overview on the Belladonna, Caffeine, Ergotamine, Pentobarbital page
“People who take Micomp PB for migraines are often the same people reaching for an herbal sleep aid or a caffeinated energy product during a rough stretch, and with four drugs in one tablet (belladonna, caffeine, ergotamine, pentobarbital) nearly everything clashes with something. The 290 supplement ingredients on file here earn genuine…”
Reviewed by 2 · Jul 18, 2026
Open the Belladonna, Caffeine, Ergotamine, Pentobarbital interaction page
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 Belladonna, Caffeine, Ergotamine, Pentobarbital 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:
Where Eucalyptus and Belladonna, Caffeine, Ergotamine, Pentobarbital 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.
#416 of 1,452 supplements looked up here in the last 7 days
#105 of 2,830 medications looked up here in the last 7 days
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.
About Eucalyptus
What is 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.
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.
No drugs match “”.
877 interactions
- Diclofenac Sodium ›
- Diltiazem ›
- Theophylline ›
- Nifedipine ›
- Ibuprofen ›
- Hydrocortisone ›
- Insulin (rdna) ›
- Naproxen ›
- Erythromycin ›
- Estradiol ›
- Propranolol ›
- Lidocaine ›
- Norethindrone ›
- Testosterone ›
- Verapamil ›
- Levonorgestrel ›
- Prednisone ›
- Quinidine ›
- Cyclosporine ›
- Dexamethasone ›
- Glyburide ›
- Insulin (pork) ›
- Triazolam ›
- Zopiclone ›
- Colchicine ›
- Fentanyl ›
- Flurbiprofen ›
- Oxybutynin ›
- Phenytoin ›
- Prednisolone ›
- Tacrolimus ›
- Temazepam ›
- Budesonide ›
- Carbamazepine ›
- Clindamycin ›
- Dextromethorphan ›
- Diclofenac Potassium ›
- Doxorubicin ›
- Fluticasone ›
- Formoterol ›
- Indomethacin ›
- Insulin (human) ›
- Miconazole ›
- Trimipramine ›
- Acetaminophen ›
- Amphetamine ›
- Buprenorphine ›
- Conjugated Estrogens ›
- Diazepam ›
- Everolimus ›
- Ivabradine ›
- Lofepramine ›
- Medroxyprogesterone ›
- Medroxyprogesterone Acetate ›
- Meloxicam ›
- Nortriptyline ›
- Rifampin ›
- Testosterone Undecanoate ›
- Acarbose ›
- Aripiprazole ›
Showing 60 of 877 moderate interactions — see all 877 on the Eucalyptus page.
No interaction 1,952 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.
- Levothyroxine ›
- Methylphenidate ›
- Ivermectin ›
- Aspirin ›
- Rosuvastatin ›
- Metoprolol ›
- Escitalopram ›
- Isotretinoin ›
- Docusate ›
- Sumatriptan ›
- Valacyclovir ›
- Hydroxyurea ›
- Levothyroxine, Liothyronine ›
- Methotrexate ›
- Amoxicillin ›
- Lisinopril ›
- Bupropion ›
- Azithromycin ›
- Pregabalin ›
- Doxycycline ›
- Gabapentin ›
- Lamotrigine ›
- Acyclovir ›
- Duloxetine ›
- Methylene Blue ›
- Ciprofloxacin ›
- Candesartan Cilexetil ›
- Amoxicillin, Clavulanate Potassium ›
- Acetylsalicylic Acid ›
- Bisoprolol ›
- Calcium Oxybate, Magnesium Oxybate, Potassium Oxybate, Sodium Oxybate ›
- Ezetimibe ›
- Aluminum Hydroxide, Aspirin, Magnesium Hydroxide ›
- Cyclopentolate ›
- Cephalexin ›
- Isoniazid, Pyrazinamide, Rifampin ›
- Atenolol, Chlorthalidone ›
- Avatrombopag Maleate ›
- Thyroid Hormone ›
- Aluminum Hydroxide, Aspirin, Codeine Phosphate, Magnesium Hydroxide ›
- Carbidopa, Levodopa ›
- Levetiracetam ›
- Aspirin, Aluminum Hydroxide, Codeine Phosphate, Magnesium Hydroxide ›
- Mannitol ›
- Bendroflumethiazide, Rauwolfia Serpentina ›
- Roxithromycin ›
- Levodopa ›
- Acetaminophen, Dextromethorphan, Doxylamine ›
- Spironolactone ›
- Enalapril Maleate ›
- Aspirin, Butalbital ›
- Ceftolozane Sulfate, Tazobactam Sodium ›
- Alginic Acid, Aluminum Hydroxide ›
- Atenolol ›
- Mitomycin ›
- Ephedrine, Phenobarbital, Theophylline ›
- Amobarbital, Ephedrine Sulfate ›
- Venlafaxine ›
- Flutemetamol F-18 ›
- Hydrocortisone, Clioquinol, Pramoxine ›
Showing the 60 most looked-up of 1,952 medications checked with no known interaction — see the full Eucalyptus list.
Sources & How We Checked
Interaction details are evidence-graded and sourced from the Natural Medicines database. The medication overview comes from MedlinePlus.
- Natural Medicines (Therapeutic Research Center) — Evidence-graded clinical reference for vitamins, herbs and supplements — the basis for our interaction data.
- MedlinePlus, U.S. National Library of Medicine — NIH consumer drug information, used for the medication overviews.
- NIH Dietary Supplement Label Database (DSLD) — Official supplement product labels.
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
Belladonna, Caffeine, Ergotamine, Pentobarbital Is Linked to Lower Levels of 2 Nutrients
Natural Medicines records Belladonna, Caffeine, Ergotamine, Pentobarbital as a medicine that can lower these. This is not an interaction with Eucalyptus — it is a separate effect of the medicine, and it is a reason some people are advised to supplement rather than to avoid one:
Read the full Belladonna, Caffeine, Ergotamine, Pentobarbital nutrient depletion report ›
Depletion records come from the licensed Natural Medicines database. Do not start a supplement on the strength of this page — ask your pharmacist or doctor whether it applies to you.
Taking Eucalyptus and Belladonna, Caffeine, Ergotamine, Pentobarbital Together: Common Questions
Can you take Eucalyptus with Belladonna, Caffeine, Ergotamine, Pentobarbital?
Why are there 3 interactions listed for Eucalyptus and Belladonna, Caffeine, Ergotamine, Pentobarbital?
How serious is the Eucalyptus and Belladonna, Caffeine, Ergotamine, Pentobarbital interaction?
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.