My Little Bit just had ACL surgery and will be taking anitbiotics and pain killers for a while. Is there a probiotic for dogs to help counter the effects of the meds?

This is a question you should be asking your veterinarian

All my vets always prescribed FortiFlora for my dogs.

TONS!!!!! Yes. Most vets don't have nutritional background, so they don't even talk to you about this.

Goat milk is an easy, cheap one.

You can add a TB our sauerkraut.

You can get a pet probiotic at your local natural pet food store.

I use Endurance by Wendy Volhard.

I have a beautiful big German Shepherd that has been given a wallop sized tablespoon of non-fat plain yogurt with several squirts of salmon oil as part of a nightly ritual. He loves it and looks forward to it daily. He gets calcium and natural probiotics (yogurt) and oil that keeps his fur shiny.