Blue cohosh, also called papoose-root or squawroot (Caulophyllum thalictroides (L.) Michx., Berberidaceae) is a perennial herb indigenous to North America. Native Americans used a decoction of the rhizome for menstrual cramps, to ease childbirth, to promote prompt delivery, for colic, cramps, and rheumatism. Dietary supplement products that contain this plant are available in the U.S. as women's "tonics." The plant contains the quinolizidine alkaloids methylcytisine, baptifoline, and anagyrine and the aporphine alkaloid magnoflorine. Some quinolizidine alkaloids, including anagyrine, have been implicated as teratogens in higher animals and their toxicity to range animals has been well documented. Because traditional use involves administration to women of reproductive age and to pregnant women in the last 3-4 weeks of pregnancy, the safety of cohosh containing products to the fetus is of some concern. The alkaloids have been determined in authentic blue cohosh and several dietary supplements. Levels found were: 3-850 ppm for methylcytisine, 2-390 ppm for anagyrine, and 9-900 ppm for baptifoline. Lowest alkaloid levels were found in liquid products. Results were confirmed by mass spectrometry.