CAUTIONS: The safety of NEXGARD Chewable Tablets hasn't been evaluated in breeding, pregnant or lactating dogs. The safety of NEXGARD in puppies below 8 weeks of age has not been evaluated.my lab puppy has worms. I've see them in his stools. Sad to say I haven't treated him for worms ahead of. I wasn't mindful of the worth. I've addressed him now b