Hello, my name is***** and I have over 20 years of experience as a veterinarian. I am sorry to hear that your fellow is vomiting undigested food and green bile phlegm. Dogs that have a gastrointestinal blockage or very abnormal intestinal motility often vomit green material as that is digested bile, bile that sits in the stomach
for a while. Bile only refluxes back into the stomach when gastrointestinal motility is abnormal, such as with a blockage or poor gastrointestinal motility due to primary intestinal or metabolic disease. Vomiting can be related to a dietary allergy or sensitivity, toxin exposure, a viral or bacterial infection, inflammatory bowel disease
, internal organ disease including kidney or liver disease, diabetes
, a full or partial gastrointestinal obstruction or even infiltrative cancers such as lymphoma
.Because your other dogs are fine an infectious cause is very unlikely. Is he a fellow that gets outdoors unsupervised or chews up toys such that he could get into something or swallow something that could lead to an obstruction or toxicity.Vomiting undigested food and green bile make odds of an obstruction higher.Because he is vomiting so much I am very concerned about him. He will quickly become dehydrated. Ideally he would see a veterinarian since this has been going on all day. Simple stomach upset should pass within 24 to 48 hours. They could examine him, run blood tests and possibly check radiographs and/or an ultrasound to evaluate him and know best how to treat him.In the meantime they can administer injectable anti-nausea drugs and fluids to rehydrate him. If you cannot have him seen right away for whatever reason there are some things you can try at home, though if he doesn't respond quickly he should see a veterinarian. I understand that you have Zofran. That anti-nausea drug is not approved for dogs although we do use in in some dogs with intractable vomiting undergoing chemotherapy or due to severe pancreatitis because we know why they are vomiting. Instead to try and settle his stomach you can give either:1) Pepcid ac (famotidine
) at a dose of one 10mg tablet per 20 to 40 pounds of body weight every 12 hours OR2) Prilosec (omeprazole) at a dose of one 20mg tablet per 40 to 80 pounds of body weight every 24 hours These are acid reducers and may help him feel better without masking important symptoms. They are quite safe and can be used for several days if necessary. You can use a medicine syringe to try and force water into him orally. A couple of hours after giving the acid reducer I recommend clear broth or a 50:50 mix of pedialyte and water.If he stops vomiting you can try offering meat baby foods or a bland diet of 1/3 boiled, minced, white, skinless chicken
or very lean, boiled hamburger and 2/3 boiled white rice mixed with some low salt chicken broth to make it easy to lap up and swallow. If he continues to vomit green material he should see her veterinarian or an emergency veterinarian for an examination, diagnostics and intravenous fluids and supportive care. Please let me know if you have any further questions.