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Dietary supplement

Comfrey Leaf Powder Ingredients & Drug Interactions

by TerraVita Premium Collection

Comfrey Leaf Powder label
See full label image
Powder Category: Botanical
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Comfrey Leaf Powder against your medications. The heart of this page is the interaction checker and the full interaction report — how this product’s ingredients may interact with prescription and over-the-counter medicines you may be taking.

Around that, we add a pharmacist’s high-level view of the product as a whole — what’s inside, the evidence for its stated use, how transparent the label is, and what safety data exists — so you can see the full picture in one place. It’s educational information from our licensed clinical databases and the clinical staff at HelloPharmacist — not medical advice — and we don’t sell or endorse products. Our editorial policy

The interaction bottom line Most serious interaction: Moderate

Comfrey Leaf Powder is a dietary supplement by TerraVita Premium Collection with 1 active ingredient. Its ingredients are commonly taken for bruises and sprains, muscle and joint pain, minor wounds and skin irritation.Based on those ingredients, 438 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Comfrey, Powder. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Comfrey Leaf Powder by TerraVita Premium Collection

Ask about any prescription or over-the-counter medication and we check it for interactions with Comfrey Leaf Powder by TerraVita Premium Collection — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Comfrey Leaf Powder by TerraVita Premium Collection

Our pharmacy team’s full take, with four database checks built into the cards below — a summary of what is known, not a grade of the product itself.

From our pharmacy team — supplement deep dive

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Jul 16, 2026

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 1 of its 1 active ingredient.
  • No proprietary blends here — you can verify the dose of every single component.

This product contains one active ingredient: comfrey powder. Comfrey has been used traditionally to support joint and bone health, though the evidence for these uses isn't well established.

The plant's active compounds are pyrrolizidine alkaloids, the same constituents responsible for its serious liver toxicity when taken by mouth.

Does it work?

Couldn't assess
Evidence for Intended Use · database check
By FDA rules, dietary supplements can’t claim to treat, cure, or prevent disease — so labels speak in careful marketing language. We discern each product’s intended use from its name, label claims, and label statements, then grade the clinical evidence for that use. How these ratings are computed
Not assessable

This is a single-ingredient Comfrey product and its label doesn't state a use — see Comfrey's own graded uses on its monograph.

Why this rating?
  • We looked at the product name, claims, and label statements and couldn't find a stated purpose to grade.

The data we hold doesn't establish that comfrey powder is effective for bronchitis, angina, back pain, cough, or cancer. For all of these conditions, the evidence is insufficient to rate it.

If you're considering comfrey for a specific health concern, talk with your doctor about whether there's better evidence for other options.

The evidence, ingredient by ingredient Comfrey

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

Adverse-effect, pregnancy, and general safety data are on file for most of these ingredients.

Why this rating?
  • We hold adverse-effect (side-effect) data for 1 of the 1 matched ingredient.
  • Pregnancy & breastfeeding safety ratings cover 1 of 1.
  • General safety write-ups exist for 1 of 1.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Comfrey is unsafe to take by mouth. Its pyrrolizidine alkaloids can cause severe liver damage—including cirrhosis, scarring, and liver failure—that may not show up for months or even years after you stop taking it.

Serious side effects also include lung damage leading to high blood pressure in the lungs, fluid buildup in the belly, and in rare cases, death. Avoid comfrey entirely during pregnancy and while breastfeeding.

The safety data advises against both because of liver toxicity and the risk of harm to your baby or infant. If applied topically to unbroken skin, comfrey is generally well tolerated, though rash, itching, and irritation can occur.

Side effects, ingredient by ingredient Comfrey

Meds to double-check

Moderate interaction found
Known Interaction Concern · database check
Moderate identified

The most serious documented interaction for these ingredients is Moderate. Check your medications for a personalized result.

Why this rating?
  • 1 of the 1 matched ingredient can interact with medications — Comfrey.
  • The most serious interaction on file is rated Moderate.
  • For scale: 439 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Before you take this product, double-check with your doctor or pharmacist if you take medications that affect your liver or seizure medications like phenobarbital. No interactions are documented for the ingredients we could check beyond these two categories, but the 439 individual medications affected by these interactions make it crucial to verify your own prescriptions.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with no assessable stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.

We recommend against taking comfrey powder by mouth—the liver risk is real and potentially severe. If you're interested in comfrey for a specific condition, talk with your doctor or pharmacist about safer alternatives with better evidence.

Pregnant or nursing? Comfrey is not an option for you.

Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI

Assessment coverage: 1 of 1 active ingredient matched to our full ingredient reviews (monographs). Based on the product label dated Apr 21, 2023.

This Scorecard evaluates available label information, ingredient evidence, and known medication-safety considerations. It does not independently verify product identity, purity, potency, contamination, or manufacturing quality. How these ratings are computed

At a glance

General information

Key facts about Comfrey Leaf Powder, straight from the product label.

Brand TerraVita Premium Collection
Barcode (UPC) 064435137502
Net contents 4 Ounce(s)
Market status On market
Date entered into DSLD Apr 21, 2023
DSLD ID 290426
Product type Botanical
Supplement form Powder
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years)
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for Comfrey Leaf Powder by TerraVita Premium Collection, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
0.25 Teaspoon(s)
Maximum serving Sizes:
0.25 Teaspoon(s)
Servings per container
113
UPC/BARCODE
064435137502
IngredientAmount% DV
Comfrey, Powder1000 mg--

Tap any ingredient to jump to its full detail below.

Label statements
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
FDA Statement of Identity

A Dietary Supplement

Brand IP Statement(s)

Copyright 2005 TerraVita - Distributed by ZooScape LLC, All Rights Reserved.

Suggested/Recommended/Usage/Directions

Directions Stir 1/4 of a teaspoon into a glass of water and consume 3 times daily, with meals.

General Statements

TerraVita is an exclusive line of premium natural products that use the finest, purest and most potent ingredients in the world. TerraVita's hallmarks are the highest possible standards of purity, potency, stability and freshness. All products are prepared with the greatest quality control, from raw materials through the entire manufacturing process, right up to the moment your product is sealed for freshness and shipped to you.

Please recycle!

FDA Disclaimer Statement

Statements not evaluated by FDA. Product not intended to diagnose, treat, cure, or prevent any disease.

Is this label outdated? Report a formula or label change and our pharmacy team will review it.

See for yourself

Comfrey Leaf Powder by TerraVita Premium Collection label

The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.

Comfrey Leaf Powder label

Label images are published by the NIH Dietary Supplement Label Database for the version of this product on file. Always read your actual product label.

View the full label (PDF)
What’s inside

The Ingredients in Comfrey Leaf Powder by TerraVita Premium Collection

This is the 1 active ingredient this product is made of. Select it to open its full monograph.

Serving size0.25 Teaspoon(s) Dosage formPowder Servings per container113 Amounts shown are per serving.

Comfrey, Powder

Interacts with
438 drugs
1000 mg per serving

Comfrey is a traditional herb used mainly on the skin for bruises, sprains, and joint pain, and some topical products show modest benefit for these us...

Comfrey, Powder monograph & interactions
Interaction report

Comfrey Leaf Powder by TerraVita Premium Collection Drug Interactions

Want to check YOUR meds against Comfrey Leaf Powder?

Ask about interactions with your drugs in plain English — “Can I take it with lisinopril?” — and we find you the answer in seconds, ingredient by ingredient.

 Go to the checker
438Drugs
438 Moderate

Ingredients driving the most interactions

Comfrey, Powder 438

Individual Drug Interactions

The ingredients in Comfrey Leaf Powder interact with 438 drugs. Click any drug to see the details.

1 of the 1 ingredient in Comfrey Leaf Powder interact with drugs. Each result below shows which ingredient is responsible. Comfrey, Powder

Each ingredient & the kinds of drugs it affects

For each ingredient in Comfrey Leaf Powder with known interactions, here are the types of medications it can affect. Open any type for the detail — or search your exact drug in the checker above.

Comfrey, Powder2 drug types · 438 drugs

Cytochrome P450 3A4 (Cyp3A4) Inducers

Theoretically, CYP3A4 inducers might increase the risk of adverse effects from the pyrrolizidine alkaloid constituents in comfrey.
CYP3A4 enzymes convert pyrrolizidine alkaloids, constituents of comfrey, to toxic metabolites. Some case reports show that enzyme inducers, such as phenobarbital, seem to enhance the toxicity of comfrey.

Likelihood Possible Evidence D
Hepatotoxic Drugs

Theoretically, comfrey might have additive adverse effects on the liver when used with hepatotoxic drugs.
Due to its pyrrolizidine alkaloid constituents, comfrey can cause hepatotoxic effects, including ascites, cirrhosis, hepatic fibrosis, hepatomegaly, and sinusoidal obstruction syndrome.

Likelihood Possible Evidence D
Comfrey, Powder full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Comfrey Leaf Powder, from the product label.

TerraVita Premium Collection

See all TerraVita Premium Collection products
Name
TerraVita Fine Whole Herbs
City
Brampton
State
Ontario
Pharmacist Counseling Corner

Comfrey Leaf Powder by TerraVita Premium Collection: Common Questions

Does Comfrey Leaf Powder by TerraVita Premium Collection interact with any medications?
Yes. Based on its ingredients, Comfrey Leaf Powder has a known interaction with 438 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Comfrey Leaf Powder contains a single active ingredient, and that one ingredient can interact with many different medications on its own. We check it against each medication and show the mechanism responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Can I take comfrey powder if I'm pregnant or breastfeeding?
No. The safety data advises against comfrey during pregnancy because of liver toxicity and possible harm to the baby, and while breastfeeding because harmful compounds may pass to your infant. Talk with your doctor or pharmacist about safe options for whatever you're trying to support during this time.
Is comfrey powder safe to take by mouth?
Oral use of comfrey is unsafe. Its pyrrolizidine alkaloid compounds can seriously damage your liver, causing scarring, fluid buildup, or liver failure—damage that may not appear until months or years later. It can also harm your lungs.
What does comfrey actually treat?
The evidence we hold doesn't establish that comfrey powder is effective for bronchitis, angina, back pain, cough, or cancer. If you're curious about comfrey for a specific condition, ask your doctor whether the evidence supports it.
I take a medication for seizures. Can I use comfrey?
No. Seizure medications like phenobarbital can actually increase comfrey's liver toxicity by speeding up how your body converts its alkaloids into more harmful forms. Talk with your doctor or pharmacist about whether this product is safe for you.
What side effects can comfrey cause?
When taken by mouth, comfrey can cause severe liver damage, including ascites (fluid in the belly), cirrhosis, and liver failure. It can also damage your lungs and cause high blood pressure in the lungs. These serious effects may develop months or years after you stop taking it.

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

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Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.

Comfrey Leaf Powder label
Go deeper

The Full Monographs Behind Comfrey Leaf Powder’s Ingredients

Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.

Herb & supplement monograph

Comfrey

Interacts with 438 drugs

Comfrey is a traditional herb used mainly on the skin for bruises, sprains, and joint pain, and some topical products show modest benefit for these uses. However, comfrey contains compounds...

Read the full Comfrey monograph →
Sources

Sources & How We Checked

Comfrey Leaf Powder's label data comes from the NIH Dietary Supplement Label Database; the ingredient interaction data is from the Natural Medicines database, reviewed by our pharmacists.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

The 13 references behind this product’s interaction data

Every citation that drives the interaction findings for this product’s ingredients, from the evidence-graded Natural Medicines (TRC Healthcare) database. Open an ingredient to browse its citations — links open the study on PubMed or the publisher’s site.

Comfrey 13 references
  1. Stewart MJ, Steenkamp V. Pyrrolizidine poisoning: a neglected area in human toxicology. Ther Drug Monit 2001;23:698-708. PubMed
  2. Food and Drug Administration. FDA Advises Dietary Supplement Manufacturers to Remove Comfrey Products From the Market. July 6, 2001. Available at: http://www.cfsan.fda.gov/~dms/dspltr06.html.
  3. Stickel F, Seitz HK. The efficacy and safety of comfrey. Public Health Nutr 2000;3:501-8. PubMed
  4. Chojkier M. Hepatic sinusoidal-obstruction syndrome: toxicity of pyrrolizidine alkaloids. J Hepatol 2003;39:437-46. PubMed
  5. Wang YP, Yan J, Fu PP, Chou MW. Human liver microsomal reduction of pyrrolizidine alkaloid N-oxides to form the corresponding carcinogenic parent alkaloid. Toxicol Lett 2005;155:411-20. PubMed
  6. Predel, H. G., Giannetti, B., Koll, R., Bulitta, M., and Staiger, C. Efficacy of a comfrey root extract ointment in comparison to a diclofenac gel in the treatment of ankle distortions: results of an observer-blind, randomized, multicenter study. Phytome
  7. Gyorik, S. and Stricker, H. Severe pulmonary hypertension possibly due to pyrrolizidine alkaloids in polyphytotherapy. Swiss.Med.Wkly. 4-4-2009;139(13-14):210-211.
  8. Giannetti, B. M., Staiger, C., Bulitta, M., and Predel, H. G. Efficacy and safety of comfrey root extract ointment in the treatment of acute upper or lower back pain: results of a double-blind, randomised, placebo controlled, multicentre trial. Br.J Spor PubMed
  9. Tanret, I. and Duh, D. [Pharmaceutical sheet. Symphytum officinale L., dermal use (Flexagile cream)]. J Pharm.Belg. 2012;(1):41-42.
  10. Laslett, L. L., Quinn, S. J., Darian-Smith, E., Kwok, M., Fedorova, T., Korner, H., Steels, E., March, L., and Jones, G. Treatment with 4Jointz reduces knee pain over 12 weeks of treatment in patients with clinical knee osteoarthritis: a randomised contr
  11. Frost R, Macpherson H, O'meara S. A critical scoping review of external uses of comfrey (Symphytum spp.). Complement Ther Med. 2013;21(6):724-45. PubMed
  12. Pabst H, Schaefer A, Staiger C, Junker-samek M, Predel HG. Combination of comfrey root extract plus methyl nicotinate in patients with conditions of acute upper or low back pain: a multicentre randomised controlled trial. Phytother Res. 2013;27(6):811-7. PubMed
  13. Smith DB, Jacobson BH. Effect of a blend of comfrey root extract (Symphytum officinale L.) and tannic acid creams in the treatment of osteoarthritis of the knee: randomized, placebo-controlled, double-blind, multiclinical trials. J Chiropr Med. 2011;10(3) PubMed

See these in context on the Comfrey monograph →

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

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