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, high-quality trials showing benefits in humans are lacking.
Bitter thistle, Carbenia benedicta, cardin, Cardo Santo, Carduus benedictus, Chardon Benit, Cnici benedicti herba, cnicus, holy thistle, Kardo-benedictenkraut, St. Benedict thistle, salonitenolide, spotted thistle.
Note: Blessed thistle should not be mistaken for milk thistle (Silybum marianus) or other members of the thistle family.
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.
Laboratory studies report that blessed thistle (and chemicals in blessed thistle such as cnicin and polyacetylene) has activity against several types of bacteria and no effects on some types. Reliable human study is lacking. 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.
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. Human research of blessed thistle as a treatment for viral infections is lacking.