Common name: St. Benedict Thistle
Botanical name: Cnicus benedictus
© Steven Foster
Parts used and where grown
Although native to Europe and Asia, blessed thistle is now cultivated in many areas of the
world, including the United States. The leaves, stems, and flowers are all used in herbal
preparations.
Blessed thistle has been
used in connection with the following conditions (refer to the
individual health concern for complete information):
Historical or traditional use (may
or may not be supported by scientific studies)
Folk medicine used blessed thistle tea for digestive problems, including gas, constipation, and stomach upset. This herb was also
used—like its well-known relative, milk
thistle1 —for liver and gallbladder diseases.
Active constituents
The sesquiterpene lactones, such as cnicin, provide the main beneficial effects of blessed
thistle in the treatment of indigestion. The
bitterness of these compounds stimulates digestive activity, including the flow of saliva and
secretion of gastric juice, which leads to improved appetite and digestion.2 Some
pharmacological evidence suggests that blessed thistle may also have anti-inflammatory
properties.3
How much is usually taken?
The German Commission E monograph recommends 4–6 grams of blessed thistle per
day.4 Alternatively, tincture (1/2 teaspoon [2 ml] three times per day) may be
used. Approximately 1/2 teaspoon (2 grams) of the dried herb can also be added to 1 cup (250
ml) of boiling water and steeped 10 to 15 minutes to make a tea. Three cups can be drunk each
day.
Are there any side effects or interactions?
Blessed thistle is generally safe and is not associated with side effects. Anyone with allergies to plants in the daisy family should
use blessed thistle cautiously.
At the time of writing, there were no well-known drug interactions
with blessed thistle.
References:1. Lust JB. The Herb Book. New York: Bantam Books, 1974,
343.
2. Bradley PR (ed). British Herbal Compendium, vol 1.
Bournemouth, Dorset, UK: British Herbal Medicine Association, 1992, 126–7.
3. Foster S. 101 Medicinal Herbs. Loveland, CO: Interweave
Press, 1998, 32–3.
4. Blumenthal M, Busse WR, Goldberg A, et al. (eds). The Complete
Commission E Monographs: Therapeutic Guide to Herbal Medicines. Boston, MA: Integrative
Medicine Communications, 1998, 92.