There are many reasons why dogs vomit foaming mucus but not diarrhea, such as food poisoning, improper diet, gastrointestinal diseases, parvovirus, canine distemper, etc. If found, you need to go to the hospital for examination in time. Dogs have sensitive gastrointestinal tracts and cannot eat many things, otherwise they will cause vomiting symptoms. You can usually feed them an appropriate amount of probiotics to help dogs regulate their intestines. Pay attention to the subsequent condition of the dog. If other complications occur, timely treatment is required.