I think that, as with all treats, you need to read the ingredients and (most importantly) be SURE that it was MADE in the USA...not manufatured. Many treats "manufactured" in the USA are products of China...a known disaster for dog food and treats.H&Q said:My 6 month old puppy was enjoying bully sticks daily at one point. They are a project for her and keep her very engaged. She developed diarrhea while we were out of town that lasted about a week. We're not certain if the bully sticks were the cause or if it was a parasite...we took her to the vet and he prescribed Flagyl and the prescription food. She seemed to recover and then developed diarrhea again as we switched back to her normal food. Our usual vet gave her Panacur and she seems to be doing better. In any case, regardless of whether or not the bully sticks contributed to the illness, The out of town vet's opinion was that there are preservatives in the bully sticks that aren't good for the dogs, and should be avoided. I'd like to here any other opinions out there.