Dogs with diarrhea must first fast. Fasting for one day can help their stomach and intestines rest and relieve diarrhea symptoms. However, your dog needs to be monitored closely to prevent dehydration or nutritional deficiencies. Afterwards, eating small meals more often can reduce the burden on the dog's gastrointestinal tract.

If your puppy has loose stools with blood (tomato-colored loose stools) and a fishy smell, it is recommended to seek medical attention as soon as possible. This situation is very serious. The most likely cause is infection with canine parvovirus (a type of viral enteritis). Parvovirus is associated with mortality in dogs. Early intervention and supportive treatment will greatly increase the survival rate.