Drug & supplement interaction

Tea Tree Oil + Valacyclovir

Valacyclovir brand name: Valtrex.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Tea Tree Oil and Valacyclovir 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 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

Tea Tree Oil and Valacyclovir

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 Valacyclovir and Tea Tree Oil 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 Tea Tree Oil at all — not against Valacyclovir, 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.

Tea Tree Oil safety at a glance

Tea Tree Oil overall Use caution Generally safe when used diluted on the skin, but it is toxic if swallowed.
Pregnancy Possibly Safe When used topically and appropriately. Read the full pregnancy detail
Breastfeeding Possibly Safe When used topically and appropriately. 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 Valacyclovir and Tea Tree Oil? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
What to actually watch for

No Interaction Found — But Data Suggests Tea Tree Oil and Valacyclovir 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. 4 of them are worth acting on rather than waiting out — marked below.

  • Unsteadiness Worth acting on Additional detail

    Tea Tree Oil

    “Orally, tea tree oil can cause ataxia and CNS depression.”

    Tea Tree Oil · Natural Medicines adverse-effect record, reported in depression.

    1 source cited
    1. 109947. Bekhof AMW, van Hunsel FPAM, van de Koppel S, Woerdenbag HJ. Safety assessment and adverse drug reaction reporting of tea tree oil (Melaleuca aetheroleum). Phytother Res 2022.

    “Orally, tea tree oil can cause or worsen systemic contact dermatitis. Topically, tea tree oil is usually well tolerated. However, it can cause allergic contact eczema and allergic contact dermatitis in some children and adults. Corticosteroids may be needed in some cases.

    In young children, ingestion of 10 mL or less of tea tree oil can cause significant ataxia, drowsiness, disorientation, and coma.”

    Tea Tree Oil · Natural Medicines adverse-effect record, reported in dermatitis.

    6 sources cited
    1. 4028. Carson CF, Riley TV, Cookson BD. Efficacy and safety of tea tree oil as a topical antimicrobial agent. J Hosp Infect 1998;40:175-8. PubMed
    2. 19168. De Groot A. C. and Weyland J. W. Systemic contact dermatitis from tea tree oil. Contact Dermatitis 1992;27(4):279-280. PubMed
    3. 658. De Groot AC. Airborn allergic contact dermatitis from tea tree oil. Contact Dermatitis 1996;35:304-5.
    4. 4027. Rubel DM, Freeman S, Southwell IA. Tea tree oil allergy: what is the offending agent? Report of three cases of tea tree oil allergy and review of the literature. Australas J Dermatol 1998;39:244-7. PubMed
    5. 4029. Bhushan M, Beck MH. Allergic contact dermatitis from tea tree oil in a wart paint. Contact Dermatitis 1997;36:117-8. PubMed
    6. 10015. Knight TE, Hausen BM. Melaleuca oil (tea tree oil) dermatitis. J Am Acad Dermatol 1994;30:423-7.. PubMed

    Valacyclovir

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

  • Confusion Worth acting on Additional detail

    Tea Tree Oil

    Recorded for Tea Tree Oil in the same Natural Medicines adverse-effect record shown under Unsteadiness above.

    Valacyclovir

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

  • A higher chance of infection Worth acting on Additional detail

    Tea Tree Oil

    “There is some concern that topical use of tea tree oil in the middle ear for treatment of ear infections might cause ototoxicity. There is preliminary evidence from animal research that preparations of pure tea tree oil can cause ototoxicity and impaired hearing. However, so far there are no reports of ototoxicity in humans.”

    Tea Tree Oil · Natural Medicines adverse-effect record, reported in drug-induced hearing loss.

    1 source cited
    1. 7025. Zhang SY, Robertson D. A study of tea tree oil ototoxicity. Audiol Neurootol 2000;5:64-8. PubMed

    Valacyclovir

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

  • An allergic reaction Worth acting on Additional detail

    Tea Tree Oil

    “Orally, tea tree oil can cause significant toxicity and should not be used. Topically, tea tree oil is generally well tolerated.

    Most Common Adverse Effects:

    Topically: Allergic reactions, burning, dryness, irritation, pruritus, redness, and stinging.”

    Tea Tree Oil · Natural Medicines adverse-effect record, reported in pruritus.

    Valacyclovir

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

  • Itching Additional detail

    Tea Tree Oil

    “Ingestion of as little as 2.5 mL of tea tree oil can cause petechial body rash. It can take up to a week for symptoms to resolve.

    Topically, tea tree oil is usually well tolerated. However, it can cause local irritation and inflammation in some patients. Treatment with topical corticosteroids may be needed in some cases. Severe allergic contact dermatitis has also been reported.”

    Tea Tree Oil · Natural Medicines adverse-effect record, reported in acne.

    6 sources cited
    1. 10011. Elliott C. Tea tree oil poisoning. Med J Aust 1993;159:830-1. PubMed
    2. 10033. Satchell AC, Saurajen A, Bell C, Barnetson RS. Treatment of interdigital tinea pedis with 25% and 50% tea tree oil solution: a randomized, placebo-controlled, blinded study. Australas J Dermatol 2002;43:175-8.. PubMed
    3. 13713. Martin KW, Ernst E. Herbal medicines for treatment of fungal infections: a systematic review of controlled clinical trials. Mycoses 2004;47:87-92. PubMed
    4. 19176. Enshaieh S, Jooya A, Siadat AH, and Iraji F. The efficacy of 5% topical tea tree oil gel in mild to moderate acne vulgaris: a randomized, double-blind placebo-controlled study. Indian J Dermatol Venereol Leprol 2007;73(1):22-25. PubMed
    5. 91442. Christoffers WA, Blömeke B, Coenraads PJ, Schuttelaar ML. Co-sensitization to ascaridole and tea tree oil. Contact Dermatitis. 2013 Sep;69(3):187-9. PubMed
    6. 91443. Corazza M, Borghi A, Gallo R, Schena D, Pigatto P, Lauriola MM, Guarneri F, Stingeni L, Vincenzi C, Foti C, Virgili A. Topical botanically derived products: use, skin reactions, and usefulness of patch tests. A multicentre Italian study. Contact Dermatiti

    Valacyclovir

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

  • A skin rash Additional detail

    Tea Tree Oil

    Recorded for Tea Tree Oil in the same Natural Medicines adverse-effect record shown under Itching above.

    Valacyclovir

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

Reported for Tea Tree Oil but not commonly for Valacyclovir: hearing loss, dry skin, drowsiness and acne.

Effects for Valacyclovir come from the ADVERSE REACTIONS section of its FDA label; effects for Tea Tree Oil 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

Tea Tree Oil in Pregnancy & Breastfeeding

Pregnancy And Lactation Possibly Safe

When used topically and appropriately.

Pregnancy And Lactation Likely Unsafe

When used orally. Ingestion of tea tree oil can be toxic.

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

From our Q&A

Questions About Tea Tree Oil or Valacyclovir

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Tea Tree Oil or Valacyclovir, 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 Valacyclovir

This page covers Tea Tree Oil only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Valacyclovir page lists 27 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), African Wild Potato (moderate), Banderol (moderate), Biofeedback (moderate) and Caffeic Acid (moderate).

By severity: 1 major · 17 moderate · 9 minor.

From our pharmacist’s overview on the Valacyclovir page

“Valacyclovir (Valtrex) works against herpes outbreaks only if enough of it gets absorbed into your blood, and most of this list threatens exactly that. Of the 27 supplements on file, 17 can change how well oral medicines like this one are absorbed, and the single major-rated entry, activated charcoal, binds drugs in the gut outright.”

Reviewed by 2 · Jul 18, 2026

Open the Valacyclovir interaction page

How much people look this up

Where Tea Tree Oil and Valacyclovir 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 Tea Tree Oil
Steady interest

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

29 days ago today
Medication Valacyclovir
Top 5%

#31 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 Tea Tree Oil reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 13, 2026. The Tea Tree Oil and Valacyclovir 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 Tea Tree Oil

What is Tea Tree Oil?

Tea Tree Oil
  • Acne
  • Fungal skin infections (athlete's foot, nail fungus)
  • Dandruff
  • Minor wounds and insect bites
  • Lice

Tea tree oil is an essential oil used on the skin for acne, fungal infections, and other skin problems, with some supportive but limited evidence. It is for topical use only and should never be swallowed, as it can be toxic. Always dilute it, do a patch test first, and check with your pharmacist or doctor before using.

Melaleuca alternifolia · Myrtaceae · Leaves and twigs (steam-distilled into essential oil) · Essential oil, creams, gels, ointments, soaps, shampoos, mouthwash

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

Tea Tree Oil: dosing

There is no official standardized dose for tea tree oil. Many skin products contain it at low concentrations, often diluted to a small percentage of the total product.The safest approach is to follow the directions on the product label and not apply more or more often than directed. If you are using pure essential oil, dilute it with a carrier oil before use. Never take it by mouth.

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

Read the full Tea Tree Oil monograph & all interactions
Medication

About Valacyclovir

What Is Valacyclovir Used For?

Brand name: Valtrex

Valacyclovir tablets are used in adults to treat cold sores (herpes labialis), genital herpes (initial and recurrent episodes), and shingles (herpes zoster). They can also be taken daily as suppressive therapy to reduce how often genital herpes outbreaks occur, and to lower the risk of passing genital herpes to a partner.

In children and adolescents, valacyclovir tablets are used to treat cold sores in those aged 12 and older, and chickenpox in those aged 2 to under 18. Valacyclovir has not been established as safe and effective for most uses in immunocompromised patients, with the exception of suppressive therapy for genital herpes in HIV-infected adults.

Most-Reported Side Effects for Valacyclovir

From FAERS, the FDA’s public side-effect reporting system (70,056 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Fatigue 4,317 reports
Nausea 3,985 reports
Diarrhea 3,648 reports
Headache 2,964 reports
Fever 2,753 reports
See full Valacyclovir drug information
Keep checking

Other Drugs & Tea Tree Oil

Browse every other medication we’ve checked against Tea Tree Oil — 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

Tea Tree Oil References

The 31 references that drive our Tea Tree Oil 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. Robbers JE, Tyler VE. Tyler's Herbs of Choice: The Therapeutic Use of Phytomedicinals. New York, NY: The Haworth Herbal Press, 1999.
  2. Foster S, Tyler VE. Tyler's Honest Herbal, 4th ed., Binghamton, NY: Haworth Herbal Press, 1999. DOI
  3. De Groot AC. Airborn allergic contact dermatitis from tea tree oil. Contact Dermatitis 1996;35:304-5.
  4. Rubel DM, Freeman S, Southwell IA. Tea tree oil allergy: what is the offending agent? Report of three cases of tea tree oil allergy and review of the literature. Australas J Dermatol 1998;39:244-7. PubMed
  5. Carson CF, Riley TV, Cookson BD. Efficacy and safety of tea tree oil as a topical antimicrobial agent. J Hosp Infect 1998;40:175-8. PubMed
  6. Bhushan M, Beck MH. Allergic contact dermatitis from tea tree oil in a wart paint. Contact Dermatitis 1997;36:117-8. PubMed
  7. Del Beccaro MA. Melaleuca oil poisoning in a 17-month-old. Vet Hum Toxicol 1995;37:557-8.
  8. Jandourek A, Vaishampayan JK, Vazquez JA. Efficacy of melaleuca oral solution for the treatment of fluconazole refractory oral candidiasis in AIDS patients. AIDS 1998;12:1033-7. DOI
  9. Zhang SY, Robertson D. A study of tea tree oil ototoxicity. Audiol Neurootol 2000;5:64-8. PubMed
  10. Bassett IB, Pannowitz DL, Barnetson RS. A comparative study of tea-tree oil versus benzoylperoxide in the treatment of acne. Med J Aust 1990;153:455-8. PubMed
  11. Jacobs MR, Hornfeldt CS. Melaleuca oil poisoning. J Toxicol Clin Toxicol 1994;32:461-4.. PubMed
  12. Elliott C. Tea tree oil poisoning. Med J Aust 1993;159:830-1. PubMed
  13. Knight TE, Hausen BM. Melaleuca oil (tea tree oil) dermatitis. J Am Acad Dermatol 1994;30:423-7.. PubMed
  14. Bruynzeel DP. Contact dermatitis due to tea tree oil. Trop Med Int Health 1999;4:630.
  15. Greig JE, Thoo SL, Carson CF, Riley TV. Allergic contact dermatitis following use of a tea tree oil hand-wash not due to tea tree oil. Contact Dermatitis 1999;41:354-5. 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 Tea Tree Oil and Valacyclovir Together: Common Questions

Is it safe to take Tea Tree Oil with Valacyclovir?
We do not list a known interaction between Tea Tree Oil and Valacyclovir. 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 Tea Tree Oil and Valacyclovir 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.
Does Valacyclovir interact with any supplements?
Yes. Valacyclovir has documented interactions with 27 supplements in our database — Tea Tree Oil is not one of them. The Valacyclovir 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 Valacyclovir and Tea Tree Oil?

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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.