My first response was that I would probably take her to the vet, depending on the severity, to which the lady responded that she would as well, but that her vet was closed that day (Sunday).
So what do you do if your dog has diarrhea and your vet is closed?
After doing some research on pets.webmd.com, their first suggestion is to let the gastrointestinal tract rest by withholding food for 24 hours. Encourage your dog to drink as much water as he wants in order to stay hydrated. You might even consider providing an electrolyte solution such as K9 Thirst Quencher or Pedialyte diluted by one-half water.
After 24 hours, ease your dog back into eating with low-fat, easily digestible foods such as white rice, cottage cheese, or chicken with the skin removed. Some other options are cooked oatmeal and cooked macaroni. The food should be separated into 3-4 meals throughout the day.
In case of emergency
It is important to seek immediate veterinary care if the diarrhea:
- is black or contains blood
- is accompanied by vomiting
- lasts for more than 24 hours
- causes your dog to appear weak or have a fever
Learn more detailed information including the causes of diarrhea in the WebMD.com article about dog diarrhea.