Why is my puppy still pooping worms a day after taking Heartgard?
Thank you for using Petco Pet Education Center, formerly Petcoach! HeartguardPlus has pyrantel as an ingredient, which kills adult and immature intestinal parasites. Depending on the stage of infection, it can take several days for all of the adult worms to die and be passed in the feces. It is normal to see different types of worms in the feces, as this product kills several types of worms, which are very common in puppies. If you notice that your puppy is continuing to have diarrhea after several days, I recommend bringing a stool sample from Blaze to your vet to determine which parasites are present. I hope this helps and wish you luck with your new puppy!
Updated on September 23rd, 2025