Drug & supplement interaction

Coltsfoot + Fenoprofen Calcium

Fenoprofen Calcium brand name: Nalfon.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Coltsfoot and Fenoprofen Calcium 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 Fenoprofen Calcium 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

Coltsfoot and Fenoprofen Calcium

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 Fenoprofen Calcium and Coltsfoot 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.

Coltsfoot safety at a glance

Coltsfoot overall Use caution May contain liver-toxic pyrrolizidine alkaloids; use only certified PA-free products, if at all.
Pregnancy Likely Unsafe When products containing hepatotoxic pyrrolizidine alkaloid (PA) constituents are used orally. Coltsfoot preparations containing hepatotoxic pyrrolizidine alkal... Read the full pregnancy detail
Breastfeeding Likely Unsafe When used orally. Hepatotoxic pyrrolizidine alkaloid (PA) constituents in coltsfoot are excreted in milk. There is insufficient reliable information available a... 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 Fenoprofen Calcium and Coltsfoot? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Fenoprofen Calcium

Interactions in our licensed database are recorded against drug classes, not just single drug names. Fenoprofen Calcium is filed under 5 classifications — including nonsteroidal anti-inflammatory drugs (nsaids), organic anion transporter 3 (oat3) substrates, organic anion transporter 1 (oat1) substrates. Coltsfoot has documented interactions with 3 drug classes — the most serious being anticoagulant/antiplatelet drugs (moderate), antihypertensive drugs (moderate) and cytochrome p450 3a4 (cyp3a4) inducers (moderate) — and none of Fenoprofen Calcium’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

Coltsfoot Does Interact With Other Medications

Coltsfoot has 374 moderate known drug interactions in our database — Fenoprofen Calcium isn’t one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Coltsfoot

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

What to actually watch for

No Interaction Found — But Data Suggests Coltsfoot and Fenoprofen Calcium 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.

  • Raised blood pressure Worth acting on Additional detail

    Coltsfoot

    “Orally, coltsfoot might cause lung damage. The major concern with coltsfoot use is its pyrrolizidine alkaloid (PA) content. These constituents can cause lung damage with pulmonary-arterial hypertension.”

    Coltsfoot · Natural Medicines adverse-effect record, reported in hypertension.

    2 sources cited
    1. 12841. Chojkier M. Hepatic sinusoidal-obstruction syndrome: toxicity of pyrrolizidine alkaloids. J Hepatol 2003;39:437-46. PubMed
    2. 12842. Roeder E. Medicinal plants in Europe containing pyrrolizidine alkaloids. Pharmazie 1995;50:83-98.

    Fenoprofen Calcium

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

  • Liver problems Worth acting on Additional detail

    Coltsfoot

    “Orally, coltsfoot might cause liver damage. Coltsfoot contains hepatotoxic pyrrolizidine alkaloids (PAs). Chronic exposure to other plants containing hepatotoxic PAs is associated with veno-occlusive disease. Sub-acute veno-occlusive disease can cause vague symptoms, including colicky pains, vomiting, diarrhea, and ascites within several days; persistent liver enlargement occurs within a few weeks.”

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

    3 sources cited
    1. 12841. Chojkier M. Hepatic sinusoidal-obstruction syndrome: toxicity of pyrrolizidine alkaloids. J Hepatol 2003;39:437-46. PubMed
    2. 12842. Roeder E. Medicinal plants in Europe containing pyrrolizidine alkaloids. Pharmazie 1995;50:83-98.
    3. 4021. WHO working group. Pyrrolizidine alkaloids. Environmental Health Criteria, 80. WHO: Geneva, 1988.

    Fenoprofen Calcium

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

  • Diarrhea / Vomiting Additional detail

    Coltsfoot

    “Orally, the major concern with coltsfoot use is its pyrrolizidine alkaloid (PA) content. These alkaloids can cause liver and lung injury. Chronic exposure to other plants containing hepatotoxic PA constituents has been associated with hepatic veno-occlusive disease. Sub-acute veno-occlusive disease can cause vague symptoms, including colicky pains, vomiting, diarrhea, and ascites within several days;”

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

    4 sources cited
    1. 12841. Chojkier M. Hepatic sinusoidal-obstruction syndrome: toxicity of pyrrolizidine alkaloids. J Hepatol 2003;39:437-46. PubMed
    2. 12842. Roeder E. Medicinal plants in Europe containing pyrrolizidine alkaloids. Pharmazie 1995;50:83-98.
    3. 4021. WHO working group. Pyrrolizidine alkaloids. Environmental Health Criteria, 80. WHO: Geneva, 1988.
    4. 18242. Freshour JE, Odle B, Rikhye S, Stewart DW. Coltsfoot as a potential cause of deep vein thrombosis and pulmonary embolism in a patient also consuming kava and blue vervain. J Diet Suppl 2012;9:149-54. PubMed

    Fenoprofen Calcium

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

Reported for Coltsfoot but not commonly for Fenoprofen Calcium: blood clots.

Effects for Fenoprofen Calcium come from the ADVERSE REACTIONS section of its FDA label; effects for Coltsfoot 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

Coltsfoot in Pregnancy & Breastfeeding

Pregnancy Likely Unsafe

When products containing hepatotoxic pyrrolizidine alkaloid (PA) constituents are used orally. Coltsfoot preparations containing hepatotoxic pyrrolizidine alkaloid (PA) constituents might be teratogenic and hepatotoxic. There is one case report of fatal hepatic veno-occlusive disease in a neonate associated with regular maternal consumption during pregnancy of an herb tea containing several pyrrolizidine alkaloid herbs, including coltsfoot. There is insufficient reliable information available about the safety of using coltsfoot products certified and labeled as hepatotoxic PA-free during pregnancy; avoid using.

Lactation Likely Unsafe

When used orally. Hepatotoxic pyrrolizidine alkaloid (PA) constituents in coltsfoot are excreted in milk. There is insufficient reliable information available about the safety of using coltsfoot products certified and labeled as hepatotoxic PA-free during lactation; 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 Fenoprofen Calcium Products Have a Food Rule — Coltsfoot Should Not Break It

At least one FDA label for a product containing Fenoprofen Calcium says to take it with food. If you take Coltsfoot on an empty stomach out of habit, keep them separate — and take Fenoprofen Calcium with a meal where the label says to.

This may not be true of your version. Food instructions belong to the product, not the ingredient: two Fenoprofen Calcium 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.

Fenoprofen Calcium may be administered with meals or with milk.

From the Dosage and Administration section of the FDA label we read for Fenoprofen Calcium — where that label names a specific product, the instruction is that product's. Read the label on DailyMed ›

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.

Everything else you take

See Every Supplement That Interacts With Fenoprofen Calcium

This page covers Coltsfoot only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Fenoprofen Calcium page lists 32 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), Siberian Cocklebur (major) and Wine (major).

By severity: 5 major · 16 moderate · 11 minor.

From our pharmacist’s overview on the Fenoprofen Calcium page

“The kidneys and the stomach lining take the brunt of any NSAID, and fenoprofen calcium (Nalfon), prescribed for arthritis and other pain, is no exception. This list of 32 interacting supplements deserves real caution; five carry a major rating, and understanding those five comes first.”

Reviewed by 2 · Jul 18, 2026

Open the Fenoprofen Calcium interaction page

One more smart check

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

We hold 60 real supplement products containing Coltsfoot, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Coltsfoot. Even though Coltsfoot itself has no known interaction with Fenoprofen Calcium, 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 Coltsfoot and Fenoprofen Calcium 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 Coltsfoot
Steady interest

#1,101 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Fenoprofen Calcium
Top half

#1,094 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 Coltsfoot reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 13, 2026. The Coltsfoot and Fenoprofen Calcium 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 Coltsfoot

What is Coltsfoot?

Coltsfoot
  • Cough
  • Sore throat
  • Bronchitis and congestion
  • Loosening mucus (expectorant)
  • Asthma symptoms

Coltsfoot is a traditional herb long used to soothe coughs and clear mucus, but solid human evidence for these uses is lacking. More importantly, the raw plant can contain liver-toxic pyrrolizidine alkaloids, so it carries real safety concerns and is best avoided unless you use a product certified to be free of these compounds.

Tussilago farfara · Asteraceae · Leaves and flowers · Tea, dried herb, tincture, syrup, capsules, lozenges

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

Coltsfoot: dosing

There is no established, standardized dose for coltsfoot, and because of the safety concerns, no dose can be considered clearly safe. Traditional products include teas, syrups, and tinctures, but the amount of active and toxic compounds can vary widely between products.If you choose to use coltsfoot despite the risks, only use a product certified to be free of pyrrolizidine alkaloids, follow the label directions exactly, and use it for the shortest time possible.

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

Read the full Coltsfoot monograph & all interactions
Medication

About Fenoprofen

What Is Fenoprofen Used For?

Brand name: Nalfon

Fenoprofen is used to relieve mild to moderate pain in adults. It also treats the signs and symptoms of rheumatoid arthritis and osteoarthritis — reducing pain, stiffness, and inflammation in the joints.

These uses are supported across fenoprofen calcium capsule products including Fenoprofen Calcium, Fenopron, and Nalfon capsules.

See full Fenoprofen drug information
Keep checking

Other Drugs & Coltsfoot

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

0Major
374Moderate
0Minor
2,455No known interaction
Moderate

374 interactions

Showing 60 of 374 moderate interactions — see all 374 on the Coltsfoot page.

No interaction 2,455 drugs checked — show the list
Evidence & sources

Coltsfoot References

The 8 references that drive our Coltsfoot 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. Roulet M, Laurini R, Rivier L, Calame A. Hepatic veno-occlusive disease in newborn infant of a woman drinking herbal tea. J Pediatr 1988;112:433-6. PubMed
  2. WHO working group. Pyrrolizidine alkaloids. Environmental Health Criteria, 80. WHO: Geneva, 1988.
  3. Chojkier M. Hepatic sinusoidal-obstruction syndrome: toxicity of pyrrolizidine alkaloids. J Hepatol 2003;39:437-46. PubMed
  4. Roeder E. Medicinal plants in Europe containing pyrrolizidine alkaloids. Pharmazie 1995;50:83-98.
  5. Wilson BE, Hobbs WN. Case report: pseudoephedrine-associated thyroid storm: thyroid hormone-catecholamine interactions. Am J Med Sci 1993;306:317-9. PubMed
  6. 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
  7. Hwang SB, Chang MN, Garcia ML, et al. L-652,469--a dual receptor antagonist of platelet activating factor and dihydropyridines from Tussilago farfara L. Eur J Pharmacol 1987;141:269-81. PubMed
  8. Freshour JE, Odle B, Rikhye S, Stewart DW. Coltsfoot as a potential cause of deep vein thrombosis and pulmonary embolism in a patient also consuming kava and blue vervain. J Diet Suppl 2012;9:149-54. 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 Coltsfoot and Fenoprofen Calcium Together: Common Questions

Is it safe to take Coltsfoot with Fenoprofen Calcium?
We do not list a known interaction between Coltsfoot and Fenoprofen Calcium. 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 Coltsfoot and Fenoprofen Calcium have any of the same side effects?
Yes — our sources link each of them separately to 4 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 Coltsfoot and Fenoprofen Calcium at the same time of day?
At least one FDA label for a product containing Fenoprofen Calcium says to take it with food. If you take Coltsfoot on an empty stomach out of habit, keep them separate and take Fenoprofen Calcium with a meal where the label says to. Food instructions belong to the product rather than the ingredient — two Fenoprofen Calcium products can differ — so check the directions on your own box. This is about absorption, not an interaction.
How was the Coltsfoot and Fenoprofen Calcium combination checked?
Interactions in our licensed database are recorded against drug classes. Fenoprofen Calcium is filed under 5 classifications, and Coltsfoot has documented interactions with 3 drug classes — none of Fenoprofen Calcium'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 Coltsfoot interact with any other medications?
Yes. Coltsfoot has 374 documented drug interactions in our database — Fenoprofen Calcium 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 Fenoprofen Calcium interact with any supplements?
Yes. Fenoprofen Calcium has documented interactions with 32 supplements in our database — Coltsfoot is not one of them. The Fenoprofen Calcium 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 Fenoprofen Calcium and Coltsfoot?

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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.