Blessed Thistle (Cnicus Benedictus L.)

by MedlinePlus

Blessed thistle leaves, stems, and flowers have traditionally been used in "bitter" tonic drinks and in other preparations taken by mouth to enhance appetite and digestion. Blessed thistle may also be included in the unproven anti-cancer herbal remedy Essiac. This herb has been tested in laboratory studies for its properties against infections, cancer, and inflammation with promising results. However, no high-quality trials have shown benefits in humans.

Synonyms

Bitter thistle, cardin, Carbenia benedicta , Chardon Benit, Cardo Santo, Carduus benedictus, Cnici benedicti Herba, cnicus, holy thistle, Kardo-benedictenkraut, St. Benedict thistle, salonitenolide, spotted thistle.

Selected combination products: Essiac (blessed thistle, burdock root, Indian rhubarb, sheep sorrel, inner bark of slippery elm, watercress, red clover, and kelp).

Note: Blessed thistle should not be mistaken for milk thistle ( Silybum marianus ) or other members of the thistle family.

Evidence

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.

Uses based on scientific evidence

Bacterial infections

Laboratory studies report that blessed thistle (and chemicals in blessed thistle such as cnicin and polyacetylene) have activity against several types of bacteria, including Bacillus subtilis , Brucella species, Escherichia coli , Proteus species, Pseudomonas aeruginosa, Staphylococcus aureus and Streptococcus . However, other studies have found no effects against Klebsiella , Pseudomonas , S. aureus , S. tyhpi , or yeast. There are no reliable studies in humans. Further evidence is necessary in this area before a firm conclusion can be drawn.

Indigestion and flatulence (gas)

Blessed thistle is traditionally believed to stimulate stomach acid secretion, and has been used as a treatment for indigestion or gas. However, there is limited scientific study in these areas. Additional research is needed before a firm conclusion can be reached.

Viral infections

Laboratory studies report no activity of blessed thistle against herpes viruses, influenza, or poliovirus. Effects of blessed thistle (or chemicals in blessed thistle called lignans) against HIV are not clear. There is no reliable human research of blessed thistle as a treatment for viral infections.

Uses based on tradition or theory

The below uses are based on tradition or scientific theories. 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.

Abortifacient, anorexia, appetite stimulant, astringent, bleeding, blood purifier, boils, breast milk stimulant, bubonic plague, cancer, cervical dysplasia, choleretic (bile flow stimulant), colds, contraceptive (birth control), diaphoretic (sweat stimulant), diarrhea, digestion enhancement, diuretic (increasing urine), expectorant, fever reducer, gallbladder disease, liver disorders, inflammation, jaundice, malaria, memory improvement, menstrual flow stimulant, menstrual disorders, painful menstruation, rabies, salivation stimulant, skin ulcers, wound healing, yeast infections.

Dosing

The below doses are based on scientific research, publications, traditional use, or expert opinion. Many herbs and supplements have not been thoroughly tested, and safety and effectiveness may not be proven. Brands may be made differently, with variable ingredients, even within the same brand. The below doses may not apply to all products. You should read product labels, and discuss doses with a qualified healthcare provider before starting therapy.

Standardization

Standardization involves measuring the amount of certain chemicals in products to try to make different preparations similar to each other. It is not always known if the chemicals being measured are the "active" ingredients. There is no widely accepted standardization for blessed thistle, although there are laboratory tests available to determine the presence of the "bitter" constituent cnicin. Pharmacopeial-grade blessed thistle is often assigned a "bitterness value" that is greater than 800.

Blessed thistle herbal preparations are often obtained from the leaves and flowers of the plant.

Adults (over 18 years old)

Tea: Traditional doses include 1.5 to 3.0 grams of dried blessed thistle flowering tops steeped in 150 milliliters of boiling water taken three times daily, or 1 to 3 teaspoons of dried blessed thistle herb in one cup of boiling water for 5 to 15 minutes taken three times daily (sometimes recommended to be used 30 minutes before meals). May be bitter in taste.

Tincture(1.5 grams of blessed thistle per liter): 7.5 to 10 milliliters by mouth taken three times daily has been used.

Liquid extract(1 gram of blessed thistle per 1 milliliter of 25% alcohol): 1.5 to 3.0 milliliters by mouth taken three times daily has been used.

Children (under 18 years old)

Not recommended due to lack of lack of reliable safety data.

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