Drug & supplement interaction

Aromatherapy + Levothyroxine

Levothyroxine brand names: Euthyrox, Levothroid, Unithroid, Synthroid, Levoxyl, and others.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Aromatherapy and Levothyroxine 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 Levothyroxine 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.

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Interaction report

Aromatherapy and Levothyroxine

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 Levothyroxine and Aromatherapy 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.

Worth understanding: our licensed dataset holds no drug-interaction record for Aromatherapy at all — not against Levothyroxine, and not against any other medication we track. This verdict therefore rests on the absence of any recorded data, not on research that looked at this combination and found nothing. We cannot rule an interaction out.

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.

Aromatherapy safety at a glance

Aromatherapy overall Use caution Generally low-risk when inhaled, but essential oils are concentrated and can irritate skin or be toxic if swallowed.
Pregnancy Possibly Unsafe When used orally. Some essential oils can cause severe side effects, including convulsions and kidney failure, when ingested in large amounts. Read the full pregnancy detail
Breastfeeding Use caution Safety is not well studied, so use cautiously and avoid applying oils near the breast or baby.

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 Levothyroxine and Aromatherapy? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
What to actually watch for

No Interaction Found — But Data Suggests Aromatherapy and Levothyroxine 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. 2 of them are worth acting on rather than waiting out — marked below.

  • Seizures Worth acting on Additional detail

    Aromatherapy

    “Ingestion of undiluted oils can sometimes result in significant adverse events including convulsions, particularly in children (8,12,19). Essential oils with proconvulsant effects include rosemary oil, eucalyptus, camphor, fennel oil, hyssop oil, pennyroyal, sage oil, cedar, and thuja. Ingestion of camphorated oil 5-30 mL by children 5 years and younger has resulted in twitch, seizure, ataxia, and coma.”

    Aromatherapy · Natural Medicines adverse-effect record, reported in epilepsy.

    6 sources cited
    1. 8. Wichtl MW. Herbal Drugs and Phytopharmaceuticals. Ed. N.M. Bisset. Stuttgart: Medpharm GmbH Scientific Publishers, 1994.
    2. 12. McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.
    3. 19. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
    4. 105042. Bahr TA, Rodriguez D, Beaumont C, Allred K. The Effects of Various Essential Oils on Epilepsy and Acute Seizure: A Systematic Review. Evid Based Complement Alternat Med. 2019;2019:6216745. PubMed
    5. 13444. Gouin S, Patel H. Unusual cause of seizure. Pediatr Emerg Care 1996;12:298-300. DOI
    6. 39583. Phelan, W. J., III. Camphor poisoning: over-the-counter dangers. Pediatrics 1976;57(3):428-431. DOI

    Levothyroxine

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

  • Shortness of breath Worth acting on Additional detail

    Aromatherapy

    “In one case report, a 34-year-old Japanese female presented with complaints of dyspnea, cough, and fever 2 weeks after initiating lavender essential oil therapy delivered via humidifier. The patient had an oxygen saturation of 88% and was diagnosed with acute eosinophilic pneumonia. Symptoms improved after a course of corticosteroids and discontinuation of aromatherapy.”

    Aromatherapy · Natural Medicines adverse-effect record, reported in cough.

    1 source cited
    1. 109979. Kodama T, Watanabe T, Mataki N, Kanoh S, Kichikawa Y. Acute eosinophilic pneumonia following aromatherapy with essential oil. Respir Med Case Rep 2022;37:101657. PubMed

    Levothyroxine

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

  • Anxiety or restlessness / Tiredness Additional detail

    Aromatherapy

    Recorded for Aromatherapy in the same Natural Medicines adverse-effect record shown under Seizures above.

    Levothyroxine

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

  • Fever Additional detail

    Aromatherapy

    Recorded for Aromatherapy in the same Natural Medicines adverse-effect record shown under Shortness of breath above.

    Levothyroxine

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

  • A skin rash Additional detail

    Aromatherapy

    “Angelica root, bergamot, cumin, distilled or expressed grapefruit, expressed lemon, expressed lime, orange, expressed bitter, and rue essential oils may have photosensitizing effects (6, 18, 11019, 90515, 90521). Bay, caraway, cinnamon, citronella, clove, cumin, lemongrass, lemon verbena, oregano, peppermint, tagetes, and thyme essential oils may have irritant effects when in contact with skin or mucus membranes.”

    Aromatherapy · Natural Medicines adverse-effect record, reported in dermatitis.

    1 source cited
    1. 57032. Schaller M and Korting HC. Allergic airborne contact dermatitis from essential oils used in aromatherapy. Clin Exp Dermatol 1995;20(2):143-145.

    Levothyroxine

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

Reported for Aromatherapy but not commonly for Levothyroxine: sun sensitivity, liver problems, kidney problems and drowsiness.

Effects for Levothyroxine come from the ADVERSE REACTIONS section of its FDA label; effects for Aromatherapy 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

Aromatherapy in Pregnancy & Breastfeeding

Pregnancy Possibly Unsafe

When used orally. Some essential oils can cause severe side effects, including convulsions and kidney failure, when ingested in large amounts.

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 Levothyroxine Products Have a Food Rule — Aromatherapy Should Not Break It

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

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.

From our Q&A

Questions About Aromatherapy or Levothyroxine

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Aromatherapy or Levothyroxine, not necessarily both, but if one is close to what you were about to ask it will usually go further than a database entry can:

Not quite your question? Ask our pharmacists directly — it is free, there is no account required, and answers usually come back within 24 hours.

Everything else you take

See Every Supplement That Interacts With Levothyroxine

This page covers Aromatherapy only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Levothyroxine page lists 50 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Tiratricol (major), Acetyl-l-carnitine (moderate), Alpha-lipoic Acid (moderate) and Ascophyllum Nodosum (moderate).

By severity: 2 major · 39 moderate · 9 minor.

From our pharmacist’s overview on the Levothyroxine page

“Levothyroxine replaces a hormone your body measures in tiny amounts, so small shifts in its blood level show up in how you feel, and I treat this list with genuine care. Nearly everything on it does one of two things: blocks the pill from being absorbed in the gut, the way everyday minerals like calcium do by binding it into complexes,…”

Reviewed by 2 · Jul 18, 2026

Open the Levothyroxine interaction page

How much people look this up

Where Aromatherapy and Levothyroxine 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 Aromatherapy
Top half

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

29 days ago today
Medication Levothyroxine
Top 10

#2 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 Aromatherapy reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 13, 2026. The Aromatherapy and Levothyroxine records this page draws on were last updated July 11, 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 Aromatherapy

What is Aromatherapy?

Aromatherapy
  • Stress and relaxation
  • Anxiety
  • Sleep problems
  • Nausea
  • Headaches
  • Mood support

Aromatherapy uses scented essential oils, usually inhaled or applied to the skin, to support relaxation and well-being. Some studies suggest it may modestly help with stress, anxiety, and nausea, but evidence is limited and it should not replace medical treatment. When used carefully, it is generally low-risk, but essential oils are concentrated and can irritate skin or cause harm if swallowed.

Essential oils distilled or pressed from various plants (flowers, leaves, bark, peel, roots) · Essential oils for diffusers, inhalers, topical blends, massage oils, bath products

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

Aromatherapy: dosing

There is no standardized dose for aromatherapy. The amount used depends on the type of oil, the product, and how it is being used (diffuser, inhaler, skin, or bath).A good general rule is to use the smallest amount that gives the effect you want, and to follow the directions on the product label. When applying oils to the skin, always dilute them in a carrier oil first.

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

Read the full Aromatherapy monograph & all interactions
Medication

About Levothyroxine

What Is Levothyroxine Used For?

Brand names: Euthyrox, Levothroid, Unithroid, Synthroid, Levoxyl, Levo-T, Eltroxin, Estre, Levothyroxine, Novothyrox, Levolet

Levothyroxine replaces or supplements the thyroid hormone your body isn't making enough of. It's used for hypothyroidism — an underactive thyroid — in adults, children, and even newborns, whether the cause is the thyroid gland itself, the pituitary gland, or the hypothalamus in the brain.

It's also used alongside surgery and radioiodine treatment in people with certain types of thyroid cancer, to help suppress the hormone that can stimulate cancer growth. It is not meant for weight loss, treating benign thyroid nodules in people who have enough iodine, or for hypothyroidism during recovery from a temporary condition called subacute thyroiditis.

See full Levothyroxine drug information
Keep checking

Other Drugs & Aromatherapy

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

0Major
0Moderate
0Minor
2,829No known interaction
No interaction 2,829 drugs checked — show the list
Evidence & sources

Aromatherapy References

The 23 references that drive our Aromatherapy 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. Wichtl MW. Herbal Drugs and Phytopharmaceuticals. Ed. N.M. Bisset. Stuttgart: Medpharm GmbH Scientific Publishers, 1994.
  2. McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.
  3. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
  4. Foster S, Tyler VE. Tyler's Honest Herbal, 4th ed., Binghamton, NY: Haworth Herbal Press, 1999. DOI
  5. Burkhard PR, Burkhardt K, Haenggeli CA, Landis T. Plant-induced seizures: reappearance of an old problem. J Neurol 1999;246:667-70. PubMed
  6. Darben T, Cominos B, Lee CT. Topical eucalyptus oil poisoning. Australas J Dermatol 1998;39:265-7. PubMed
  7. Gouin S, Patel H. Unusual cause of seizure. Pediatr Emerg Care 1996;12:298-300. DOI
  8. Phelan, W. J., III. Camphor poisoning: over-the-counter dangers. Pediatrics 1976;57(3):428-431. DOI
  9. Gibson, D. E., Moore, G. P., and Pfaff, J. A. Camphor ingestion. Am.J.Emerg.Med. 1989;7(1):41-43.
  10. Theis, J. G. and Koren, G. Camphorated oil: still endangering the lives of Canadian children. CMAJ. 6-1-1995;152(11):1821-1824.
  11. Skoglund, R. R., Ware, L. L., Jr., and Schanberger, J. E. Prolonged seizures due to contact and inhalation exposure to camphor. A case report. Clin.Pediatr.(Phila) 1977;16(10):901-902. PubMed
  12. Janes, S. E., Price, C. S., and Thomas, D. Essential oil poisoning: N-acetylcysteine for eugenol-induced hepatic failure and analysis of a national database. Eur.J Pediatr 2005;164(8):520-522. PubMed
  13. 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.
  14. Hindle, R. C. Eucalyptus oil ingestion. N.Z.Med J 5-11-1994;107(977):185-186.
  15. 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

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 Aromatherapy and Levothyroxine Together: Common Questions

Is it safe to take Aromatherapy with Levothyroxine?
We do not list a known interaction between Aromatherapy and Levothyroxine. 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 Aromatherapy and Levothyroxine have any of the same side effects?
Yes — our sources link each of them separately to 6 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 Aromatherapy and Levothyroxine at the same time of day?
At least one FDA label for a product containing Levothyroxine 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 Levothyroxine on its own and move Aromatherapy 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.
Does Levothyroxine interact with any supplements?
Yes. Levothyroxine has documented interactions with 50 supplements in our database — Aromatherapy is not one of them. The Levothyroxine interaction page linked on this page lists every one, ranked by severity.

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

Still Have a Question About Levothyroxine and Aromatherapy?

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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.