Coltsfoot

Botanical

What is it

Coltsfoot (Tussilago farfara) is a perennial herb in the daisy family with a long traditional history for cough and respiratory complaints. However, it contains hepatotoxic pyrrolizidine alkaloids (PAs) that have raised serious safety concerns.

Evidence for 1 use

AI-assisted evidence assessment — talk to your doctor before relying on any single supplement.

Cough / respiratory complaints

Limited Evidence

Traditional use is well-established and Commission E recognizes the indication, but safer alternatives (honey, marshmallow, elder, thyme) exist without the PA concerns.

How it works

Coltsfoot contains mucilage (which can soothe irritated throats and airways), polysaccharides, and flavonoids that may contribute to antitussive and expectorant effects. However, it also contains pyrrolizidine alkaloids (senkirkine and senecionine), which are converted to toxic intermediates in the liver and can cause veno-occlusive disease. PA-free cultivars have been developed and are used in some European herbal products. Wild or non-PA-free preparations carry serious hepatotoxicity risk, particularly with long-term or high-dose use.

Dosage

Traditional doses: 1-2 g of dried herb as tea, 2-3 times daily. PA-free products only should be used; even then, courses should be limited to 4-6 weeks per year per Commission E and ESCOP guidance.

When and how to take it

WHEN: Limited courses only (4-6 weeks per year). HOW: Use only PA-free certified products. Consult a clinician for cough lasting more than a few days.

2 commercial forms

Compare the main delivery options and what they’re best suited for.

Dried herb (PA-containing)

Not recommended due to safety concerns.

Use is restricted or banned in many jurisdictions

PA-free coltsfoot

Used in some European herbal products; limit use duration.

Selectively bred to lack pyrrolizidine alkaloids

Safety

Significant safety concerns due to pyrrolizidine alkaloid content. PA-containing coltsfoot can cause hepatic veno-occlusive disease, hepatic failure, and possibly carcinogenic effects. Germany restricts coltsfoot to products with PA content below 1 mcg/day, with maximum 4-6 weeks use per year.

Who should be cautious

Avoid in pregnancy and lactation (PAs cross placenta and into breast milk). Avoid in liver disease. Avoid in infants and children. Avoid long-term use even with PA-free products. We generally do not recommend coltsfoot supplementation given alternative cough remedies.

Interactions

Potential interactions with hepatotoxic medications, hormonal medications (some PAs are estrogenic), and immunosuppressants. Should be avoided with other hepatotoxic herbs (comfrey, borage).

Frequently asked questions

Is coltsfoot safe?

Standard coltsfoot contains hepatotoxic pyrrolizidine alkaloids that can cause serious liver damage. Use only PA-free certified products for limited periods (4-6 weeks per year max).

Are there safer alternatives for cough?

Yes. Honey (in adults and children over 1 year), marshmallow root, slippery elm, thyme, and elder are well-established cough remedies without coltsfoot's hepatotoxicity risk.

References

Coltsfoot on WikidataWikidata link

Coltsfoot on NIH DSLD (US supplement label database)NIH Dietary Supplement Label Database link

Research on Coltsfoot (PubMed search)PubMed link

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Evidence-based·How we grade evidence

Disclaimer: These statements have not been evaluated by the FDA. This page is educational, not a substitute for personalized medical advice. Evidence grades are AI-assisted assessments — talk to your doctor before starting any new supplement, especially if you’re pregnant, breastfeeding, on medications, or managing a chronic condition.