Drug & supplement interaction

Thuja + Naproxen

Naproxen brand names: Naprosyn, Naprelan, Anaprox, Anaprox DS, Naproxyn, and others.

No Known Interaction
Medically reviewed by · Updated July 2026 · Pair last verified Sep 13, 2026
The bottom line No known interaction

We found no known interaction between Thuja and Naproxen 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

Thuja and Naproxen

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 Naproxen and Thuja 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.

Thuja safety at a glance

Thuja overall Use caution The plant and especially its essential oil contain thujone, which can be toxic if taken internally in large amounts.
Pregnancy Likely Unsafe When used orally due to abortifacient activity; avoid using. Read the full pregnancy detail
Breastfeeding Likely Unsafe When used orally due to toxicity; avoid using. 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 Naproxen and Thuja? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Naproxen

Interactions in our licensed database are recorded against drug classes, not just single drug names. Naproxen is filed under 10 classifications — including nonsteroidal anti-inflammatory drugs (nsaids), cytochrome p450 2c9 (cyp2c9) substrates, anticoagulant/antiplatelet drugs. Thuja has documented interactions with 3 drug classes — the most serious being anticonvulsants (moderate), immunosuppressants (moderate) and seizure threshold lowering drugs (moderate) — and none of Naproxen’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

Thuja Does Interact With Other Medications

Thuja has 576 moderate known drug interactions in our database — Naproxen isn’t one of them. If you take anything else, check it against the full list below.

Moderate 576 No known interaction 2,254 (incl. Naproxen)
Taking anything else?

Check Another of Your Medications Against Thuja

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

What to actually watch for

No Interaction Found — But Data Suggests Thuja and Naproxen 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.

  • Kidney problems Worth acting on Additional detail

    Thuja

    “Orally, large doses of thuja have been reported to cause toxicity involving headache, nervous agitation, seizures, gastric irritation, vomiting, abdominal pain, and diarrhea. Thuja toxicity has also been reported to cause liver damage, renal toxicity, and death in some cases.”

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

    2 sources cited
    1. 6002. Fetrow CW, Avila JR. Professional's Handbook of Complementary & Alternative Medicines. 1st ed. Springhouse, PA: Springhouse Corp., 1999.
    2. 40888. Naser, B., Bodinet, C., Tegtmeier, M., and Lindequist, U. Thuja occidentalis (Arbor vitae): A Review of its Pharmaceutical, Pharmacological and Clinical Properties. Evid.Based Complement Alternat.Med 2005;2(1):69-78.

    Naproxen

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

  • Liver problems Worth acting on Additional detail

    Thuja

    “Orally, large doses of thuja have been reported to cause toxicity involving liver damage and death. In one case report, a healthy 40-year-old female taking thuja and black cohosh for 1 month presented with 3 days of severe abdominal pain and AST and ALT levels exceeding 5 times the upper limit of normal. Symptoms improved within 5 days of supplement discontinuation and levels normalized within 2 weeks.”

    Thuja · Natural Medicines adverse-effect record, reported in pain.

    3 sources cited
    1. 6002. Fetrow CW, Avila JR. Professional's Handbook of Complementary & Alternative Medicines. 1st ed. Springhouse, PA: Springhouse Corp., 1999.
    2. 40888. Naser, B., Bodinet, C., Tegtmeier, M., and Lindequist, U. Thuja occidentalis (Arbor vitae): A Review of its Pharmaceutical, Pharmacological and Clinical Properties. Evid.Based Complement Alternat.Med 2005;2(1):69-78.
    3. 106047. Patel R, Alavi F, Ortega S, Matela A. Herb-Induced Liver Injury by Cimicifuga racemosa and Thuja occidentalis Herbal Medications for Fertility. Case Rep Gastrointest Med 2021;2021:8858310. PubMed

    Naproxen

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

  • Anxiety or restlessness Additional detail

    Thuja

    “Orally, large doses of thuja have been reported to cause toxicity involving nervous agitation, seizures, and death.”

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

    2 sources cited
    1. 6002. Fetrow CW, Avila JR. Professional's Handbook of Complementary & Alternative Medicines. 1st ed. Springhouse, PA: Springhouse Corp., 1999.
    2. 40888. Naser, B., Bodinet, C., Tegtmeier, M., and Lindequist, U. Thuja occidentalis (Arbor vitae): A Review of its Pharmaceutical, Pharmacological and Clinical Properties. Evid.Based Complement Alternat.Med 2005;2(1):69-78.

    Naproxen

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

  • Stomach upset / Stomach pain / Diarrhea / Vomiting reported in 6.0% of FDA reports for Naproxen Additional detail

    Thuja

    “Orally, large doses of thuja have been reported to cause toxicity involving gastric irritation, vomiting, abdominal pain, and diarrhea.”

    Thuja · Natural Medicines adverse-effect record, reported in diarrhea.

    2 sources cited
    1. 6002. Fetrow CW, Avila JR. Professional's Handbook of Complementary & Alternative Medicines. 1st ed. Springhouse, PA: Springhouse Corp., 1999.
    2. 40888. Naser, B., Bodinet, C., Tegtmeier, M., and Lindequist, U. Thuja occidentalis (Arbor vitae): A Review of its Pharmaceutical, Pharmacological and Clinical Properties. Evid.Based Complement Alternat.Med 2005;2(1):69-78.

    Naproxen

    Listed in the ADVERSE REACTIONS section of the FDA label for Naproxen, and in voluntary FDA adverse-event reports. Read the label on DailyMed ›

  • Headache reported in 6.4% of FDA reports for Naproxen Additional detail

    Thuja

    Recorded for Thuja in the same Natural Medicines adverse-effect record shown under Kidney problems above.

    Naproxen

    Listed in the ADVERSE REACTIONS section of the FDA label for Naproxen, and in voluntary FDA adverse-event reports. Read the label on DailyMed ›

  • A skin rash Additional detail

    Thuja

    “Contact dermatitis, presenting as an itchy papular squamous eruption on the hands, developed in a 46-year-old female who handled thuja plants while gardening. It resolved when contact with thuja was avoided. The causative ingredient of thuja was identified as limonene.

    In one case report, a 5-year-old female presented with a papillary eccrine adenoma.”

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

    2 sources cited
    1. 113415. Badaoui A, Fougerousse AC. Contact dermatitis to linalool and limonene: Unusual sources of exposure. Ann Dermatol Venereol 2023;150(2):167-168. PubMed
    2. 106048. Ambooken B, Thomas M, Jisha KT. Papillary Eccrine Adenoma in a 5-year-old Girl Altered by Application of Thuja Ointment. J Cutan Aesthet Surg 2020;13(4):370-371. PubMed

    Naproxen

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

Reported for Thuja but not commonly for Naproxen: seizures.

Effects for Naproxen come from the ADVERSE REACTIONS section of its FDA label; effects for Thuja come from the Natural Medicines adverse-effect record, quoted above. Where a percentage is shown, it is the share of 165,062 voluntary FDA FAERS reports for Naproxen that mention that effect — a reporting proportion, not an incidence rate and not evidence the drug caused it. Wording is matched across sources by our own clinical vocabulary, so treat this as a prompt to pay attention, not a diagnosis.

Special populations

Thuja in Pregnancy & Breastfeeding

Pregnancy Likely Unsafe

When used orally due to abortifacient activity; avoid using.

Lactation Likely Unsafe

When used orally due to toxicity; 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

Overlapping uses

What Naproxen Is Prescribed For, and What Thuja Has Been Studied For

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

Naproxen is prescribed for: Naproxen tablets, naproxen sodium tablets, and naproxen oral suspension are used to relieve the signs and symptoms of rheumatoid arthritis, osteoarthritis, ankylosing spondylitis, and polyarticular juvenile idiopathic arthritis. They are also used for tendonitis, bursitis, and acute gout, and for managing pain and primary dysmenorrhea (menstrual cramps). Naproxen Sodium Controlled-Release Tablets are indicated for the same conditions plus the relief of mild to moderate pain. Several over-the-counter naproxen sodium products are indicated for the temporary relief of minor aches and pains from headache, backache, muscular aches, toothache, menstrual cramps, minor arthritis pain, and the common cold, and to temporarily reduce fever.

Thuja has been studied for:

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

    Thuja for common cold

    Clinical research in patients with moderate cold symptoms shows that taking three tablets of a specific combination product (Esberitox, Schaper & Brümmer GmbH & Co. KG) containing dry extracts of echinacea root, thuja leaf, and wild indigo root three times daily for 7-9 days improves the severity of cold symptoms, general well-being, and overall response rate when compared with placebo.

    1 source cited
    1. 6392. Henneicke-von Zepelin H, Hentschel C, Schnitker J, et al. Efficacy and safety of a fixed combination phytomedicine in the treatment of the common cold (acute viral respiratory tract infection): results of a randomised, double blind, placebo-controlled, m

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 Naproxen on your own; if you are taking Thuja for the same health topic, tell your prescriber, especially if the medicine is being adjusted to a target.

From our Q&A

Questions About Thuja or Naproxen

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

This page covers Thuja only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Naproxen page lists 311 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Asarabacca (major), Beer (major), Danshen (major) and Piracetam (major).

By severity: 7 major · 260 moderate · 44 minor.

Open the Naproxen interaction page

One more smart check

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

We hold 84 real supplement products containing Thuja, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Thuja. Even though Thuja itself has no known interaction with Naproxen, 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 Thuja and Naproxen 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 Thuja
Top half

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

29 days ago today
Medication Naproxen
Top 5%

#57 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 Thuja reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 13, 2026. The Thuja and Naproxen 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 Thuja

What is Thuja?

  • Warts and skin growths
  • Respiratory and immune support
  • Cold and upper respiratory symptoms
  • Topical skin conditions
  • Traditional use as a diuretic or to bring on menstruation

Thuja, also called northern white cedar or arborvitae, is a tree whose leaf and oil have a long history in folk and homeopathic medicine, especially for warts and immune support. Solid human evidence for these uses is very limited, and the undiluted oil contains thujone, which can be toxic. Talk with a pharmacist or doctor before using it, and avoid it during pregnancy and breastfeeding.

Thuja occidentalis · Cupressaceae · Leaves (young twigs/branch tips) and essential oil · Homeopathic pellets, tinctures, topical ointments, essential oil, capsules, and combination cold/immune products

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

Thuja: dosing

There is no well-established standard dose for thuja, and products vary widely in strength. Homeopathic pellets, tinctures, and topical creams all use different concentrations.Because the essential oil contains potentially toxic thujone, it should not be taken by mouth without professional guidance.

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

Read the full Thuja monograph & all interactions
Medication

About Naproxen

What Is Naproxen Used For?

Brand names: Naprosyn, Naprelan, Anaprox, Anaprox DS, Naproxyn, Navalbine, Naproxen, Naprosyn EC, Napro-Na, Aleve, Arthroxen, Synflex, EC-Naprosyn

Naproxen tablets, naproxen sodium tablets, and naproxen oral suspension are used to relieve the signs and symptoms of rheumatoid arthritis, osteoarthritis, ankylosing spondylitis, and polyarticular juvenile idiopathic arthritis. They are also used for tendonitis, bursitis, and acute gout, and for managing pain and primary dysmenorrhea (menstrual cramps).

Naproxen Sodium Controlled-Release Tablets are indicated for the same conditions plus the relief of mild to moderate pain. Several over-the-counter naproxen sodium products are indicated for the temporary relief of minor aches and pains from headache, backache, muscular aches, toothache, menstrual cramps, minor arthritis pain, and the common cold, and to temporarily reduce fever.

Most-Reported Side Effects for Naproxen

From FAERS, the FDA’s public side-effect reporting system (165,062 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Fatigue 13,047 reports
Nausea 12,185 reports
Arthralgia 11,086 reports
Headache 10,504 reports
Diarrhea 9,841 reports
See full Naproxen drug information
Keep checking

Other Drugs & Thuja

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

0Major
576Moderate
0Minor
2,253No known interaction
576 Moderate 2,253 No interaction
Moderate

576 interactions

Showing 60 of 576 moderate interactions — see all 576 on the Thuja page.

No interaction 2,253 drugs checked — show the list

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

Showing the 60 most looked-up of 2,253 medications checked with no known interaction — see the full Thuja list.

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

Thuja References

The 10 references that drive our Thuja 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. Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.
  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. Millet Y, Jouglard J, Steinmetz MD, et al. Toxicity of some essential plant oils. Clinical and experimental study. Clin Toxicol 1981;18:1485-98. PubMed
  4. Gohla SH, Haubeck HD, Neth RD. Mitogenic activity of high molecular polysaccharide fractions isolated from the Cupressaceae Thuja occidentale L. I. Macrophage-dependent induction of CD-4-positive T-helper (Th+) lymphocytes. Leukemia 1988;2:528-33.
  5. Fetrow CW, Avila JR. Professional's Handbook of Complementary & Alternative Medicines. 1st ed. Springhouse, PA: Springhouse Corp., 1999.
  6. Henneicke-von Zepelin H, Hentschel C, Schnitker J, et al. Efficacy and safety of a fixed combination phytomedicine in the treatment of the common cold (acute viral respiratory tract infection): results of a randomised, double blind, placebo-controlled, m
  7. Naser, B., Bodinet, C., Tegtmeier, M., and Lindequist, U. Thuja occidentalis (Arbor vitae): A Review of its Pharmaceutical, Pharmacological and Clinical Properties. Evid.Based Complement Alternat.Med 2005;2(1):69-78.
  8. Patel R, Alavi F, Ortega S, Matela A. Herb-Induced Liver Injury by Cimicifuga racemosa and Thuja occidentalis Herbal Medications for Fertility. Case Rep Gastrointest Med 2021;2021:8858310. PubMed
  9. Ambooken B, Thomas M, Jisha KT. Papillary Eccrine Adenoma in a 5-year-old Girl Altered by Application of Thuja Ointment. J Cutan Aesthet Surg 2020;13(4):370-371. PubMed
  10. Badaoui A, Fougerousse AC. Contact dermatitis to linalool and limonene: Unusual sources of exposure. Ann Dermatol Venereol 2023;150(2):167-168. 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 Thuja and Naproxen Together: Common Questions

Is it safe to take Thuja with Naproxen?
We do not list a known interaction between Thuja and Naproxen. 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 Thuja and Naproxen 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.
Are Thuja and Naproxen 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 Thuja in each. That is a conversation for your prescriber, especially if Naproxen is being adjusted to a target.
How was the Thuja and Naproxen combination checked?
Interactions in our licensed database are recorded against drug classes. Naproxen is filed under 10 classifications, and Thuja has documented interactions with 3 drug classes — none of Naproxen'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 Thuja interact with any other medications?
Yes. Thuja has 576 documented drug interactions in our database — Naproxen 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 Naproxen interact with any supplements?
Yes. Naproxen has documented interactions with 311 supplements in our database — Thuja is not one of them. The Naproxen 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

Thuja monograph Uses, safety profile, and every drug interaction in one place Naproxen drug information The full plain-English guide to this medication Naproxen supplement interactions Every supplement checked against Naproxen, 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 10 citations behind this page Ask a pharmacist Free, personal answer from our licensed team

Still Have a Question About Naproxen and Thuja?

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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.