something else that helped me during Lola's diarrhea week from hell is a medication that can be applied to her butt to ease the pain. I am not sure about your pup but Lola's butt was so inflamed and raw that she was afraid to poop because it hurt so bad. she would back herself in the corner and sit down with the most scared look on her face, it was pitiful to watch. I happened to tell a friend who had just had anal surgery, she had a crème that was a combination of antespic and numbing that she said would take the pain away. it worked immediately. As a precaution I did have to put a cone on her head, because unlike humans dogs tend to lick an area that hurts and we did not want her licking the crème. I am not a proponent of using human medicines on dogs but in this instance it was a life saver. I think Lola still remembers the pain because every once in a while she will have a bad poop that sticks to her and she acts like no other dog I have seen, she gets in a corner and has that same scared and concerned look on her face, in an instant my husband and I know what's wrong, we call it Lola's poopy butt face
