Dog diarrhea is defined as an abnormal increase in the amount of fluid in the feces. It is often followed by excessively loose, watery and frequent stools. As a dog-owner, you probably know what this means. A sick dog, a stinky mess, countless trips outside, and a miserable experience for both you and your dog. Diarrhea may be short in duration, but can also last for weeks or months. The bad news: nearly all dogs get diarrhea sooner or later. The good news: most cases are mild and self-limiting. This article may help you be better prepared when diarrhea strikes.