Updated August 12, 2015.

Written or reviewed by a board-certified physician. See About.com's Medical Review Board.

Blessed thistle (Cnicus benedictus) is a plant that has been a part of herbal medicine since the Middle Ages. It has been used as a diuretic, a treatment for loss of appetite and indigestion, and as a stimulant for milk production in nursing mothers. Originally from the Mediterranean, this prickly plant now grows in many places throughout the world.

Health Benefits and Uses of Blessed Thistle

• It is believed to help increase a low breast milk supply.

• It has been used to treat diseases of the liver, gallbladder, stomach and intestines.
• It is believed to decrease gas and help with indigestion.
• It is used to improve appetite.
• It may help with depression by elevating mood.

Blessed Thistle and Breastfeeding

Blessed thistle is believed to be a galactagogue, taken to help make more breast milk. It appears to work best when used in combination with fenugreek, however, it can also be used with fennel, alfalfa, stinging nettle and goat's rue. Some commercially prepared teas and products such as Traditional Medicinal's Mother's Milk Tea or Motherlove's More Milk and More Milk Plus contain blessed thistle along with other herbs that promote milk production.

How to Use Blessed Thistle

Before taking blessed thistle, talk to your doctor or lactation consultant.

As a Tea: () Use 1 or 2 teaspoons of dried blessed thistle per cup (8 oz) of boiling water. Drink up to 3 cups per day. Blessed thistle tea is bitter so it can be mixed with other dry herbs for a more pleasant taste.

Capsules: () Blessed thistle capsules are available. A typical dose is up to 3 capsules 3 times a day.

Warnings and Side Effects

Always consult your doctor before taking any supplements including herbs. Herbs have been used as medications for centuries. They can have side effects and interfere with other medications you may be taking. It is also important to let your baby's doctor know if you are taking any medications, herbs or supplements and breastfeeding.

Do not use blessed thistle during pregnancy. Blessed thistle is a uterine stimulant which can potentially induce a miscarriage or cause preterm labor.

Diarrhea, vomiting and stomach upset can occur when taking large amounts of blessed thistle.

Avoid using blessed thistle if you have an ulcer or other gastric issues. This herb increases the production of stomach acid, bile and saliva.

Blessed thistle is part of the Asteraceae family of plants which also includes ragweed, daisies and sunflowers. If you have an allergy to these plants you should avoid blessed thistle.

Due to the increase in stomach acid, use of blessed thistle could interfere with antacids and medications used to reduce heartburn.

In Conclusion

Blessed thistle is a common herb used by nursing mothers who wish to increase their supply of breast milk. It is most often taken in conjunction with fenugreek or as an ingredient in commercially prepared supplements designed specifically for supporting milk production in breastfeeding women. In general it appears to be safe when used in moderation, however, there are not enough reliable studies available to determine the true effectiveness or safety of blessed thistle.

<sub>Sources:

Humphrey, Sheila. The Nursing Mother's Herbal. Fairview Press. Minneapolis. 2003.

MedlinePlus. Blessed Thistle. U.S. National Library of Medicine. National Medicines Comprehensive Database. 2012. Accessed July 25, 2012: http://www.nlm.nih.gov/medlineplus/druginfo/natural/94.html

Newman, Jack. Herbs for Increasing Milk Supply. Canadian Breastfeeding Foundation. 2009. Accessed July 25, 2012: http://canadianbreastfeedingfoundation.org/induced/herbs.shtml

NYU Langone Medical Center. Blessed Thistle. EBSCO Publishing. 2012: Accessed July 25, 2012: http://www.med.nyu.edu/content?ChunkIID=104588</sub>