Observe if the dog has diarrhea and/or is vomiting. This may be an allergic reaction to food or something the dog swallowed that he wasn't supposed to, and is often nothing to worry about, however, it could be an indication of something more serious. If the vomiting lasts more than a day or if the diarrhea lasts more than a few days or contains blood, mucous or is black and tarry, a vet needs to check it.
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MELISSA MAROFF, eHOW PETS EXPERT
Melissa writes for various publications on a range of subjects, including her most favorite: pets. She's covered everything from animal activists to dog parks for magazines like WHERE, Valley Scene and The Pet Press and was a writer/editor for the Dallas Times Herald. A former stand-up comic; she's appeared on A&E, VH1 and Comedy Central. Melissa lives with her husband and two mixed-breed rescue dogs and is in search of a purse big enough to carry the 80 lb. one shopping with her on Rodeo Drive.