Pepto-Bismol can safely be given to most breeds of dogs in an effort to resolve diarrhea, according to Robert Silver. Do not give it for more than five days and never give it to cats as it is potentially toxic. In addition, a 24-hour rice fast can be effective.
Usually diarrhea is due to stress or dietary issues, notes Silver, writer for The Bark. However, there are times when medical attention is necessary for a dog with diarrhea. Black tarry or bright red stools, frequent vomiting, signs of abdominal distress, lethargy and loss of appetite are all warning signs a dog should be seen by a veterinarian.