Our vet finally stopped all meds for Giardia when three rounds did not work, and told me to find a quality food. I used FortiFlora after reading about it here. There is also something called ProPectalin gel but it’s hard to find and gets expensive. I switched the dog to Fromm, kept up probiotics and a little pumpkin in the kibble and it eventually went away on its own. Dogs can get rid of Giardia on their own as their systems mature. I’m not sure all those meds are good for them or necessary.