"Cat's Claw (Uncaria tomentosa)
Is a giant woody vine that grows in the Peruvian tropical forests. It has properties that help in resistant cases of imbalanced intestinal flora, infection, sluggish digestion, poor assimilation, and bile stimulation. It is very effective as an intestinal cleanser and immune system rejuvenator, possessing antimicrobial and antiinflammatory properties. It has the ability similar to white blood cells to engulf and digest harmful microorganisms. It is a good companion herb for treating most parasites except Giardia, which actually thrives when there is bile stimulation. It is virtually nontoxic, but should not be used by pregnant women. "

http://www.innvista.com/health/microbes/parasite/treatpar.htm