Berberine has demonstrated significant antimicrobial activity against bacteria, fungi, yeast, protozoans (Giardia, etc.), viruses, helminths (worms) and chlamydia. In addition, berberine's actions include: antagonism of the effects of cholera and E. coli toxin, inhibition of intestinal ion secretion, inhibition of smooth muscle contraction (spasms), and reduction of inflammation.

Berberine's most common Traditional Chinese Medicine uses include: bacterial, diarrhea and intestinal parasites. Other uses of Berberine may offer anti-infective qualities, actually inhibiting the adhesion of disease cells (bacteria, fungi, parasites, etc.) to the body's host cells, thus crippling the disease cell before it can do any damage. It may do this by causing the disease cell to lose lipoteinchoic acid (LTA) which is the major substance responsible for the adhesion of bacteria (and other disease cells) to host tissues.