When my 85-year-old mother was very sick with e coli, the doctor wanted to put her on antibiotics. I didn't want to do that to her, so I asked a local pharmacist, who is also an herbalist, if he could recommend anything. He recommended a form of Cat's Claw, which I gave her. Within a couple of hours she was up and wanting to do the dishes!
I have used it myself, with similar results, for infections and viruses, etc. What it does is strengthen your immune system and fix your DNA, apparently. It seems to be ok to take it regularly, if you wish. Do watch the expiry date, though, as it does appear to lose effectiveness over time.
HOWEVER, children and women who are pregnant, wish to be, or breastfeeding should NOT take it, as I have seen warnings against that. Apparently it is even used as a type of birth control in some areas where it is grown.