What is it?
Today, blessed thistle is prepared as a tea and used for loss of appetite and indigestion; and to treat colds, cough, fever, bacterial infections, and diarrhea. It is also used as a diuretic for increasing urine output, and for promoting the flow of breast milk in new mothers.
Some people soak gauze in blessed thistle and apply it to the skin for treating boils, wounds, and ulcers.
In manufacturing, blessed thistle is used as a flavoring in alcoholic beverages.
Don’t confuse blessed thistle with milk thistle (Silybum marianum).
How effective is it?
Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, Ineffective, and Insufficient Evidence to Rate.
The effectiveness ratings for BLESSED THISTLE are as follows:
Insufficient evidence to rate effectiveness for...
- Promoting milk flow in breast-feeding mothers.
- Promoting urine flow.
- Other conditions.
How does it work?
Are there safety concerns?
Special precautions & warnings:Pregnancy and breast-feeding: Don’t take blessed thistle by mouth if you are pregnant. There is some evidence that it might not be safe during pregnancy. It’s also best to avoid blessed thistle if you are breast-feeding. Not enough is known about the safety of this product.
Intestinal problems, such as infections, Crohn's disease, and other inflammatory conditions: Don’t take blessed thistle if you have any of these conditions. It might irritate the stomach and intestines.
Allergy to ragweed and related plants: Blessed thistle may cause an allergic reaction in people who are sensitive to the Asteraceae/Compositae 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 blessed thistle.
Are there interactions with medications?
- Antacids are used to decrease stomach acid. Blessed thistle may increase stomach acid. By increasing stomach acid, blessed thistle might decrease the effectiveness of antacids.
Some antacids include calcium carbonate (Tums, others), dihydroxyaluminum sodium carbonate (Rolaids, others), magaldrate (Riopan), magnesium sulfate (Bilagog), aluminum hydroxide (Amphojel), and others.
- Medications that decrease stomach acid (H2-blockers)
- Blessed thistle might increase stomach acid. By increasing stomach acid, blessed thistle might decrease the effectiveness of some medications that decrease stomach acid, called H2-blockers.
Some medications that decrease stomach acid include cimetidine (Tagamet), ranitidine (Zantac), nizatidine (Axid), and famotidine (Pepcid).
- Medications that decrease stomach acid (Proton pump inhibitors)
- Blessed thistle might increase stomach acid. By increasing stomach acid, blessed thistle might decrease the effectiveness of medications that are used to decrease stomach acid, called proton pump inhibitors.
Some medications that decrease stomach acid include omeprazole (Prilosec), lansoprazole (Prevacid), rabeprazole (Aciphex), pantoprazole (Protonix), and esomeprazole (Nexium).
Are there interactions with herbs and supplements?
- There are no known interactions with herbs and supplements.
Are there interactions with foods?
- There are no known interactions with foods.
What dose is used?
To learn more about how this article was written, please see the Natural Medicines Comprehensive Database methodology.
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