If you decide to take the antibiotic...I would definitely take the probiotics along with it...maybe even double up on them. If you are able to obtain some Florastor it would also be good to take with the Antibiotics ...it's a probiotic that has been routinely distributed along with Antibiotics in Europe in order to prevent some of the complications with Antibiotic therapy...and has recently become available in the US. I don't know if it is available in health food stores...perhaps you could run a search and find out. Somebody else will have to advise you about the Threelac.