U?a de caballo

Related Terms

Ass's foot, Asteraceae (family), bull's foot, butterbur, colt's foot, cough plant, coughwort, farfara, foal's foot, foalswort, horse foot, horse-hoof, kuandong hua, pyrrolizidine alkaloids, tussilago, Tussilagofarfara, winter heliotrope.

Background

Coltsfoot (Tussilago farfara), a member of the Asteraceae family, is native to Europe and Asia. It is presumed to have been introduced to the United States by settlers for medicinal purposes. Today, coltsfoot has spread into the northern and middle Atlantic, Midwest, and northern Pacific areas of the United States. It is currently listed as a noxious or invasive weed in several states in the United States.
The leaves and flowering stems of coltsfoot have a long history of medicinal use as an expectorant (to release mucus) and cough suppressant, hence the name tussilago, which translates to cough suppressant. Coltsfoot has been used to treat other respiratory conditions, including asthma, emphysema, and smoker's cough. Coltsfoot has also been used as an astringent, as a demulcent (to soothe mucous membranes), and as a poultice for eczema, skin ulcers, insect bites, and other inflammatory skin conditions.
The flowers and young leaves are edible and may be consumed either raw or cooked. The rootstock has been used to make a sweet syrup.

Evidence Table

These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider. GRADE *
These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider. GRADE *
* Key to grades

A: Strong scientific evidence for this use
B: Good scientific evidence for this use
C: Unclear scientific evidence for this use
D: Fair scientific evidence for this use (it may not work)
F: Strong scientific evidence against this use (it likley does not work)
* Key to grades

A: Strong scientific evidence for this use
B: Good scientific evidence for this use
C: Unclear scientific evidence for this use
D: Fair scientific evidence for this use (it may not work)
F: Strong scientific evidence against this use (it likley does not work)

Tradition / Theory

The below uses are based on tradition, scientific theories, or limited research. They often have not been thoroughly tested in humans, and safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider. There may be other proposed uses that are not listed below.

Dosing

Adults (18 years and older)
There is no proven safe or effective dose for coltsfoot in adults.

Safety

The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Consult a healthcare provider immediately if you experience side effects.

Interactions

Interactions with Drugs
Coltsfoot may increase the risk of bleeding when taken with drugs that increase the risk of bleeding. Some examples include aspirin, anticoagulants (blood thinners) such as warfarin (Coumadin?) or heparin, antiplatelet drugs such as clopidogrel (Plavix?), and nonsteroidal anti-inflammatory drugs such as ibuprofen (Motrin?, Advil?) or naproxen (Naprosyn?, Aleve?).
Coltsfoot may raise blood pressure. Caution is advised in patients taking drugs that affect blood pressure.
Coltsfoot may interact with antiasthma drugs, anti-inflammatory agents, calcium channel blockers, cough suppressants, drugs that may damage the liver, or expectorants.

Attribution

This information is based on a systematic review of scientific literature edited and peer-reviewed by contributors to the Natural Standard Research Collaboration (www.naturalstandard.com).

Bibliography

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