Quick Summary

Coltsfoot (Tussilago farfara) is a traditional medicinal plant primarily used for respiratory ailments such as cough and bronchitis. It contains phytochemicals, including pyrrolizidine alkaloids, which have potential hepatotoxicity, raising safety concerns. Clinical evidence regarding its efficacy is limited and mostly indirect, with some studies evaluating multi-herb formulas containing Coltsfoot rather than the herb alone. Due to potential liver toxicity associated with pyrrolizidine alkaloids, safety considerations are essential.

What Is It?

Coltsfoot is a perennial herb native to Europe and parts of Asia, recognized by its hoof-shaped leaves and yellow flowers. Traditionally, the leaves and flowers have been used as herbal remedies, especially for respiratory conditions.

Traditional Uses

  • Cough relief
  • Bronchitis treatment
  • Support for acute lower respiratory infections
  • Adjunctive use in viral respiratory infections (including in traditional formulations for COVID-19)

Active Compounds

The herb contains several bioactive constituents, notably:

  • Pyrrolizidine alkaloids (PAs): Known for potential hepatotoxic effects.
  • Tussilagone: A compound studied for anti-inflammatory properties in preclinical models.
  • Other phytochemicals typical of medicinal herbs, contributing to traditional use effects.

Potential Benefits with Evidence Levels

  • Respiratory symptoms (e.g., cough, bronchitis, acute lower respiratory infections) – Moderate evidence
    Meta-analyses of Chinese herbal formulas containing Coltsfoot showed improved clinical efficacy, faster symptom resolution, reduced inflammation, and fewer adverse events in lower respiratory infections (You et al., 2020; Xu et al., 2025). Direct high-quality trials on Coltsfoot alone are currently lacking.
  • Anti-inflammatory effects – Preclinical/Animal evidence
    Tussilagone demonstrated anti-inflammatory effects in cell and animal models, reducing inflammatory mediators and improving survival in sepsis model mice (Kim et al., 2017).
  • Adjunctive use in viral respiratory infections including COVID-19 – Low to moderate indirect evidence
    Traditional Chinese Medicine (TCM) formulas containing Coltsfoot have been used in COVID-19 treatment, with systematic reviews indicating potential symptom improvement and acceptable safety profiles (Ang et al., 2022; Wang et al., 2021; Ding et al., 2022). However, effects cannot be attributed to Coltsfoot alone.
  • Potential anticancer properties – Insufficient / Preclinical evidence
    General reviews highlight anticancer potential of phytochemicals from various plants, but no specific clinical evidence exists for Coltsfoot (Ali et al., 2023; Aljabali et al., 2025).

Side Effects

  • Potential hepatotoxicity, including liver injury and hepatic sinusoidal obstruction syndrome (HSOS), likely due to pyrrolizidine alkaloids
  • Gastrointestinal symptoms such as nausea and vomiting reported, possibly related to the herbal formulas containing Coltsfoot
  • No significant serious adverse events reported in controlled clinical trials of multi-herb formulas containing Coltsfoot

Drug Interactions

No specific documented drug interactions for Coltsfoot alone were identified in current evidence. However, because pyrrolizidine alkaloids may impact liver metabolism and the herb is metabolized by liver enzymes, caution is warranted when combining with drugs metabolized hepatically. Further research is needed.

Who Should Avoid It

  • Individuals with liver disease or impaired liver function, due to potential hepatotoxicity
  • Patients with known hypersensitivity to Coltsfoot or related species
  • Pregnant or breastfeeding women, as safety data are insufficient and hepatotoxicity risk exists; use only under medical supervision

Evidence Limitations

  • Most clinical data come from studies on multi-herb Traditional Chinese Medicine formulas containing Coltsfoot, not the herb alone
  • Lack of high-quality randomized controlled trials directly evaluating Coltsfoot’s efficacy and safety
  • Existing meta-analyses show heterogeneity and some publication bias
  • Limited data on long-term safety and adverse effects
  • Predominance of preclinical and in vitro evidence for anti-inflammatory and anticancer mechanisms
  • Potential hepatotoxic risk from pyrrolizidine alkaloids necessitates further clinical evaluation and regulatory oversight

References

  • You Q, Li L, Li D, et al. (2020). Meta-Analysis on the Chinese Herbal Formula Xiaoer-Feike Granules as a Complementary Therapy for Children With Acute Lower Respiratory Infections. Frontiers in Pharmacology. DOI: 10.3389/fphar.2020.496348. Europe PMC
  • Xu X, Hu G, Yu Y, et al. (2025). Efficacy and safety of Xiaoer Feike Granules combined with azithromycin for Mycoplasma pneumoniae pneumonia: A systematic review and meta-analysis. Europe PMC. DOI: 10.1097/md.0000000000044287. Europe PMC
  • Kim YK, Yeo MG, Oh BK, et al. (2017). Tussilagone Inhibits the Inflammatory Response and Improves Survival in CLP-Induced Septic Mice. International Journal of Molecular Sciences. DOI: 10.3390/ijms18122744. Europe PMC
  • Ang L, Song E, Hu XY, et al. (2022). Herbal Medicine Intervention for the Treatment of COVID-19: A Living Systematic Review and Cumulative Meta-Analysis. Frontiers in Pharmacology. DOI: 10.3389/fphar.2022.906764. Europe PMC
  • Teschke R, Vongdala N, Quan NV, et al. (2021). Metabolic Toxification of 1,2-Unsaturated Pyrrolizidine Alkaloids Causes Human Hepatic Sinusoidal Obstruction Syndrome: The Update. International Journal of Molecular Sciences. DOI: 10.3390/ijms221910419. Europe PMC
  • Quan NV, Dang Xuan T, Teschke R. (2020). Potential Hepatotoxins Found in Herbal Medicinal Products: A Systematic Review. International Journal of Molecular Sciences. DOI: 10.3390/ijms21145011. Europe PMC
  • Zong X, Liang N, Wang J, et al. (2022). Treatment Effect of Qingfei Paidu Decoction Combined With Conventional Treatment on COVID-19 Patients and Other Respiratory Diseases: A Multi-Center Retrospective Case Series. Frontiers in Pharmacology. DOI: 10.3389/fphar.2022.849598. Europe PMC

Last Reviewed

June 2024

Disclaimer

The information provided here is for educational purposes only and does not constitute medical advice. Coltsfoot may have potential risks, particularly related to liver toxicity. Always consult a qualified healthcare provider before using any herbal supplement, particularly if you have underlying health conditions, are pregnant or breastfeeding, or are taking prescription medications.