Drug & supplement interaction

Pleurisy Root + Levothyroxine

Levothyroxine brand names: Euthyrox, Levothroid, Unithroid, Synthroid, Levoxyl, 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 Pleurisy Root 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

Pleurisy Root 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 Pleurisy Root 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.

Pleurisy Root safety at a glance

Pleurisy Root overall Use caution It contains potentially toxic compounds and has little safety data, so use cautiously and under guidance.
Pregnancy Avoid Traditionally used to stimulate the uterus and considered unsafe in pregnancy.
Breastfeeding Possibly Unsafe When used orally; 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 Levothyroxine and Pleurisy Root? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Levothyroxine

Interactions in our licensed database are recorded against drug classes, not just single drug names. Levothyroxine is filed under 3 classifications — including thyroid hormone, oral drugs. Pleurisy Root has documented interactions with 3 drug classes — the most serious being digoxin (lanoxin) (major), diuretic drugs (moderate) and estrogens (moderate) — and none of Levothyroxine’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

Pleurisy Root Does Interact With Other Medications

Pleurisy Root has 1 major, 116 moderate known drug interactions in our database — Levothyroxine isn’t one of them. If you take anything else, check it against the full list below.

Major 1 Moderate 116 No known interaction 2,713 (incl. Levothyroxine)
Taking anything else?

Check Another of Your Medications Against Pleurisy Root

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

What to actually watch for

No Interaction Found — But Data Suggests Pleurisy Root 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.

  • Muscle weakness Worth acting on Additional detail

    Pleurisy Root

    “Orally, pleurisy root can cause gastrointestinal irritation, nausea, and vomiting (19). When consumed in large quantities, pleurisy root may cause digitalis-like poisoning symptoms (18). Acute digitalis poisoning symptoms include gastrointestinal upset, contracted pupils, blurred vision, strong slow pulse, nausea, vomiting, dizziness, excessive urination, fatigue, muscle weakness and tremors, stupor, confusion, convu…”

    Pleurisy Root · Natural Medicines adverse-effect record, reported in arrhythmia.

    5 sources cited
    1. 19. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
    2. 18. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.
    3. 6. The Review of Natural Products by Facts and Comparisons. St. Louis, MO: Wolters Kluwer Co., 1999.
    4. 159. Gossel TA, Bricker JD. Principles of Clinical Toxicology. New York, NY:Raven Press, 1994.
    5. 501. De Smet PAGM, Keller K, Hansel R, Chandler RF, Eds. Adverse Effects of Herbal Drugs 1. Verlag, Berlin: Springer, 1992. DOI

    Levothyroxine

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

  • Seizures Worth acting on Additional detail

    Pleurisy Root

    “Orally, consuming large quantities of pleurisy root may cause digitalis-like poisoning symptoms (18). Acute digitalis poisoning symptoms include dizziness, stupor, confusion, convulsions, and fatigue (6,159,501).”

    Pleurisy Root · Natural Medicines adverse-effect record, reported in fatigue.

    4 sources cited
    1. 18. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.
    2. 6. The Review of Natural Products by Facts and Comparisons. St. Louis, MO: Wolters Kluwer Co., 1999.
    3. 159. Gossel TA, Bricker JD. Principles of Clinical Toxicology. New York, NY:Raven Press, 1994.
    4. 501. De Smet PAGM, Keller K, Hansel R, Chandler RF, Eds. Adverse Effects of Herbal Drugs 1. Verlag, Berlin: Springer, 1992. DOI

    Levothyroxine

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

  • Tiredness Additional detail

    Pleurisy Root

    Recorded for Pleurisy Root in the same Natural Medicines adverse-effect record shown under Muscle weakness above.

    Levothyroxine

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

  • A skin rash Additional detail

    Pleurisy Root

    “Topically, pleurisy root may cause dermatitis (19).”

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

    1 source cited
    1. 19. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.

    Levothyroxine

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

  • Vomiting / Nausea Additional detail

    Pleurisy Root

    “Orally, pleurisy root can cause gastrointestinal irritation, nausea, and vomiting (19). When consumed in large quantities, pleurisy root may cause digitalis-like poisoning symptoms (18). Acute digitalis poisoning symptoms include nausea, vomiting, and gastrointestinal upset (6,159,501).”

    Pleurisy Root · Natural Medicines adverse-effect record, reported in nausea and vomiting.

    5 sources cited
    1. 19. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
    2. 18. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.
    3. 6. The Review of Natural Products by Facts and Comparisons. St. Louis, MO: Wolters Kluwer Co., 1999.
    4. 159. Gossel TA, Bricker JD. Principles of Clinical Toxicology. New York, NY:Raven Press, 1994.
    5. 501. De Smet PAGM, Keller K, Hansel R, Chandler RF, Eds. Adverse Effects of Herbal Drugs 1. Verlag, Berlin: Springer, 1992. DOI

    Levothyroxine

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

Reported for Pleurisy Root but not commonly for Levothyroxine: stomach upset, blurred vision, a slow heartbeat and dizziness.

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

Pleurisy Root in Pregnancy & Breastfeeding

Lactation Possibly Unsafe

When used orally; 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 Levothyroxine Products Have a Food Rule — Pleurisy Root Should Not Break It

At least one FDA label for a product containing Levothyroxine says to take it on an empty stomach. Most supplements — Pleurisy Root 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 Pleurisy Root 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 Pleurisy Root 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 Pleurisy Root 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 Pleurisy Root 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 Pleurisy Root 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 Pleurisy Root
Top half

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

What is Pleurisy Root?

  • Respiratory congestion
  • Pleurisy and chest discomfort
  • Coughs and bronchitis
  • Promoting sweating during fevers
  • Loosening mucus

Pleurisy root is the dried root of Asclepias tuberosa (butterfly weed), a plant used in traditional North American and herbal medicine mainly for respiratory complaints. There is very little modern scientific evidence that it works for any condition, and it contains compounds that can be toxic, so caution is strongly advised. Pregnant and breastfeeding people should avoid it, and anyone considering it should check with a pharmacist or doctor first.

Asclepias tuberosa · Apocynaceae · Dried root · Tea, tincture, capsules, dried root

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

Pleurisy Root: dosing

There is no well-established or standardized dose for pleurisy root, and the strength of products can vary widely. Because of its potential toxicity, more is not better and self-dosing can be risky.If you choose to use a commercial product, follow the directions on the label and do not exceed them.

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

Read the full Pleurisy Root 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 & Pleurisy Root

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

1Major
116Moderate
0Minor
2,712No known interaction
1 Major 116 Moderate 2,712 No interaction
Major

1 interaction

Moderate

116 interactions

Showing 60 of 116 moderate interactions — see all 116 on the Pleurisy Root page.

No interaction 2,712 drugs checked — show the list

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

Showing the 60 most looked-up of 2,712 medications checked with no known interaction — see the full Pleurisy Root list.

See the full Pleurisy Root interactions page
See every supplement checked against Levothyroxine, ranked by severity
Evidence & sources

Pleurisy Root References

The 7 references that drive our Pleurisy Root 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. Newall CA, Anderson LA, Philpson JD. Herbal Medicine: A Guide for Healthcare Professionals. London, UK: The Pharmaceutical Press, 1996.
  2. The Review of Natural Products by Facts and Comparisons. St. Louis, MO: Wolters Kluwer Co., 1999.
  3. McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.
  4. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.
  5. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
  6. Gossel TA, Bricker JD. Principles of Clinical Toxicology. New York, NY:Raven Press, 1994.
  7. De Smet PAGM, Keller K, Hansel R, Chandler RF, Eds. Adverse Effects of Herbal Drugs 1. Verlag, Berlin: Springer, 1992. DOI

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 Pleurisy Root and Levothyroxine Together: Common Questions

Is it safe to take Pleurisy Root with Levothyroxine?
We do not list a known interaction between Pleurisy Root 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 Pleurisy Root 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 Pleurisy Root 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 Pleurisy Root 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.
How was the Pleurisy Root and Levothyroxine combination checked?
Interactions in our licensed database are recorded against drug classes. Levothyroxine is filed under 3 classifications, and Pleurisy Root has documented interactions with 3 drug classes — none of Levothyroxine'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 Pleurisy Root interact with any other medications?
Yes. Pleurisy Root has 117 documented drug interactions in our database — Levothyroxine 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 Levothyroxine interact with any supplements?
Yes. Levothyroxine has documented interactions with 50 supplements in our database — Pleurisy Root 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

Where next

Keep Exploring

Pleurisy Root monograph Uses, safety profile, and every drug interaction in one place Levothyroxine drug information The full plain-English guide to this medication Levothyroxine supplement interactions Every supplement checked against Levothyroxine, 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 7 citations behind this page Ask a pharmacist Free, personal answer from our licensed team

Still Have a Question About Levothyroxine and Pleurisy Root?

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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.