Hello, my name is***** and I have over 20 years of experience as a veterinarian. I am sorry that you have been waiting for a response, but your requested expert isn't online which delayed your question coming up on the list for all to answer. I would like to help if you are still interested in an opinion.I am sorry to hear that King isn't feeling well, lethargic with a hunched back and lack of an appetite, as well as feeling warm. I recommend taking his temperature rectally as dogs will always feel warm to us because they are relative to us. Our normal body temperature is 98.7F, whereas there's is 100F to 102.5F, so they are always 1-3 degrees warmer than we are. He is likely dehydrated because he isn't drinking, which will only make him feel worse. In most cases these sorts of symptoms are triggered by eating something they should not, too much table food, too many treats
or something they find outdoors.More serious causes of vomiting in puppies include viral or bacterial infections, a dietary allergy or sensitivity, congenital internal organ failure (kidney or liver disease), or a full or partial gastrointestinal obstruction. In a young dog, especially one that hasn't finished his vaccine series, a viral infection such as Parvo
virus or a foreign body leading to a partial or full gastrointestinal obstruction would be the most likely cause and both can be deadly. Not all dogs with viral infections run a fever initially, sometimes they are too weak to mount a fever response.Because he is young, and he is lethargic ideally he would see a veterinarian now. Young puppies dehydrate easily and he needs fluids. If that isn't possible for whatever reason there are some things we can try at home, but we cannot replace in clinic intravenous fluids and injectable medications so if he isn't responding quickly he should see a veterinarian promptly. To try and settle his stomach
you can give either:1) Pepcid ac (famotidine
) at a dose of one quarter of a 10mg tablet per 5 to 10 pounds of body weight every 12 hours OR2) Prilosec (omeprazole) at a dose of one quarter of a 20mg tablet per 10 to 20 pounds of body weight every 24 hours These are acid reducers and may help him feel less nauseous and hopefully improve his appetite. They are quite safe and can be used for several days if necessary. I would pick up all food for now and water for a couple hours to allow his stomach to settle after giving one of the acid reducers. In a couple hours when you give him water make sure it is in small amounts only or give him ice cubes to lick. If he drinks too much too quickly that can lead to vomiting. To get some electrolytes in you can also offer him a 50:50 mix of pedialyte and water. If there is no vomiting in 6 hours offer a bland diet of 1/3 boiled, minced, white skinless chicken
or boiled, lean hamburger and 2/3 boiled, white rice mixed with some low salt chicken or beef broth to make it easy to lap up and swallow and get additional fluids into him. If he refuses that, you can offer a little meat baby food. If he refuses both then don't push it, he needs hands on veterinary care as soon as possible. But if things go well and he does eat the bland diet and doesn't vomit feed him the bland diet for 3 to 4 days then slowly start to mix back in his regular food, a little more at each meal. It should take about 5 to 7 days to slowly convert him back to his regular diet. If he continues to not eat and remains lethargic even with the acid reducers, truly runs a fever (more than 103F rectally), or has a lower than normal temperature (less than 99F), has a tense painful belly, or if he refuses to eat even after the acid reducer is given he should see a veterinarian for an examination, diagnostics, injectable anti-nausea drugs, intravenous fluids and supportive care. Please let me know if you have any further questions.