Cankerwort, Common Ragwort, Dog Standard, European Ragwort, Fleur de Jacob, Herbe Dorée, Herbe de Saint-Jacques, Hierba Cana, Hierba de Santiago, Jacobée, Ragweed, Ragwort, Senecio jacobaea, Séneçon de Jacob, Séneçon Jacobée, Staggerwort, Stammerwort, St. James' Wort, Stinking Nanny.
Tansy ragwort is an herb. The flowering parts are used to make medicine.
Despite serious safety concerns, tansy ragwort is used to treat cancer, colic, wounds, and spasms. It is also used as a laxative, to cause sweating, to start menstruation, and for “cleansing and purification.”
Some people apply tansy ragwort directly to the skin for muscle and joint pain.
How does it work?
There isn't enough information available to understand how tansy ragwort works.
Insufficient Evidence to Rate Effectiveness for...
- Menstrual problems.
- Muscle and joint pain, when applied to the skin.
- Other conditions.
Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, and Insufficient Evidence to Rate (detailed description of each of the ratings).
There's a lot of concern about using tansy ragwort as medicine, because it contains chemicals called hepatotoxic pyrrolizidine alkaloids (PAs), which may block blood flow in the veins and cause liver damage. Hepatotoxic PAs might also cause cancer and birth defects. Tansy ragwort preparations that are not certified and labeled “hepatotoxic PA-free” are considered UNSAFE.
It's also UNSAFE to apply tansy ragwort to broken skin. The dangerous chemicals in tansy ragwort can be absorbed quickly through broken skin and can lead to dangerous body-wide toxicity. Steer clear of skin products that aren't certified and labeled “hepatotoxic PA-free.” There isn't enough information to know if it's safe to apply tansy ragwort to unbroken skin. It's best to avoid use.
It's also UNSAFE to use tansy ragwort preparations that might contain hepatotoxic PAs if you are breast-feeding. These chemicals can pass into breast-milk and might harm the nursing infant.
It's not known whether products that are certified hepatotoxic PA-free are safe to use during pregnancy or breast-feeding. Stay on the safe side and avoid using any tansy ragwort preparation if you are pregnant or breast-feeding.
Allergy to ragweed and related plants: Tansy ragwort may cause an allergic reaction in people who are allergic to the Asteraceae/Compositae plant family. Members of this family include ragweed, chrysanthemums, marigolds, daisies, and many others. If you have allergies, be sure to check with your healthcare provider before taking tansy ragwort.
Liver disease: There is concern that the hepatotoxic PAs in tansy ragwort might make liver disease worse. Stay on the safe side and avoid using any tansy ragwort preparation if you have liver disease.
Medications that increase break down of other medications by the liver (Cytochrome P450 3A4 [CYP3A4] inducers)Interaction Rating: Major Do not take this combination.
Tansy ragwort is broken down by the liver. Some chemicals that form when the liver breaks down tansy ragwort can be harmful. Medications that cause the liver to break down tansy ragwort might enhance the toxic effects of chemicals contained in tansy ragwort.
The appropriate dose of tansy ragwort depends on several factors such as the user's age, health, and several other conditions. At this time there is not enough scientific information to determine an appropriate range of doses for tansy ragwort. Keep in mind that natural products are not always necessarily safe and dosages can be important. Be sure to follow relevant directions on product labels and consult your pharmacist or physician or other healthcare professional before using.
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