I had giardia and couldn't take any medication at all as I was nursing a baby at the time. Most people will recover from giIardia on their own if they have to. You took antibiotics. Thin you wiped out your gut flora? I'm battling this right now after two full weeks on strong antibiotics for a tooth issue. I simply take a probiotic and then focus on prebiotics (pickles, sauerkraut, kombucho tea, etc.). I use true life probiotics. If you go to a health food store, in the refrigerator section they have live probiotics. It is pricey which is why I just stuck with the pill but probably very beneficial.