Hiya Anthony!

I've researched and researched into Pau D'arco and no one seems to know how exactly it kills bacteria or fungus. Some Antibiotics like garlic, for instance, thin or even strip the protective outer cellular walls of the baddie and leave it more sucseptable (sp?) to aging and being killed by other bacteria or suffocating or disintegrating.

I suppose it's possible that it can target only yeast and leave things like acidophulis alone, as acidophulis has a different cellular structure, but... over time? Who can say?

So I take a conservative view of saying go ahead and use things like Pau D'arco, and use it a LOT, because if you're going to do it might as well do it right, but only for like a week to ten days.

After that it's easy enough to replenish the good microbes nowadays with all the wonderful probiotics that are available, so whether or not Pau D'arco kills the friendlies isn't as much of a major concern as it was in the past. :)

And as always I must add that I was able to bring my body back into balance without using any Antibiotic or anti-fungal, beyond a fondness for cooking with garlic. ;)