Blessed Thistle

Last Editorial Review: 6/11/2021
Other Name(s):

Carbenia Benedicta, Cardo Bendito, Cardo Santo, Carduus, Carduus Benedictus, Chardon Béni, Chardon Bénit, Chardon Marbré, Cnici Benedicti Herba, Cnicus, Cnicus benedictus, Holy Thistle, Safran Sauvage, Spotted Thistle, St. Benedict Thistle.

Overview

Blessed thistle is a plant. People use the flowering tops, leaves, and upper stems to make medicine. Blessed thistle was commonly used during the Middle Ages to treat the bubonic plague and as a tonic for monks.

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 does work?

Blessed thistle contains tannins which might help diarrhea, coughs, and inflammation. However, there isn't enough information to know how well blessed thistle might work for many of its uses.

QUESTION

Next to red peppers, you can get the most vitamin C from ________________. See Answer

Uses

Insufficient Evidence to Rate Effectiveness for...

  • Diarrhea.
  • Coughs.
  • Infections.
  • Boils.
  • Wounds.
  • Promoting milk flow in breast-feeding mothers.
  • Promoting urine flow.
  • Other conditions.
More evidence is needed to rate the effectiveness of blessed thistle for these uses.

Side Effects

Blessed thistle might be safe for most people. In high doses, such as more than 5 grams per cup of tea, blessed thistle can cause stomach irritation and vomiting.

Precautions

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.

Interactions


AntacidsInteraction Rating: Minor Be cautious with this combination.Talk with your health provider.

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)Interaction Rating: Minor Be cautious with this combination.Talk with your health provider.

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)Interaction Rating: Minor Be cautious with this combination.Talk with your health provider.

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).

Dosing

The appropriate dose of blessed thistle 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 blessed thistle. 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.

SLIDESHOW

Vitamin D Deficiency: How Much Vitamin D Is Enough? See Slideshow

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).

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References

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