Supplement Forms/Alternate Names:

  • Cnicus benedictus


Blessed thistle is a plant that grows in North America. It can be taken as a pill or powder. Its leaves can also be made into a tea.


There aren’t any advised doses for blessed thistle.

What Research Shows

There is not enough data to support that blessed thistle is helpful in treating health problems. We will review future studies as they are published.

Editorial process and description of evidence categories can be found at EBSCO NAT Editorial Process.

Safety Notes

It is likely safe for most people to take blessed thistle for a short time. People with certain plant allergies may have an allergic reaction to blessed thistle. Not enough studies have been done to say whether it is safe to take for a long period.


Talk to your doctor about any supplements or therapy you would like to use. Some can interfere with treatment or make conditions worse, such as:

  • People with plant allergies should talk to their doctor before taking blessed thistle. It may cause a reaction.


REF1 Bruno M, Rosselli S, Maggio A, et al. Antibacterial evaluation of cnicin and some natural and semisynthetic analogues. Planta Med . 2003;69:277–81.

REF2 Barrero AF, Oltra JE, Alvarez M, et al. New sources and antifungal activity of sesquiterpene lactones. Fitoterapia . 2000;71:60–4.

Revision Information

  • Reviewer: EBSCO NAT Review Board Eric Hurwitz, DC
  • Review Date: 05/2019
  • Update Date: 02/14/2020