Like to hear your final solution.
Would like to give my two cents, go find a raw milk cow or goat producer near you or find them online and get real kefir grains. You will make your own cultures probiotic drink every. Day to several days where a cup of this nector will give you between 2-2.5 trillion beneficial support to your gut which many of the hundreds of strains will stay inside you to populate gut and even grow with added support.
If your going store bought do research and pick one with at least 10-20 types of bacteria.