Thank you for your question.
I have just come online and am sorry to see that this hasn't been answered before now. Still I wanted to give my thought to you since your wee one sounds to be quite severely affected here.
When we see a dog show vomiting and diarrhea, we do have to consider a range of causes. The most common reasons for a dog his age to show these signs are dietary indiscretion (eating something he shouldn’t have), ingestion of a foreign body (ie toys, bones, trash, etc.), viral infections (ie parvo, distemper, etc), toxins, intestinal parasitism, and a bacterial gastroenteritis. If he isn't a mischievous wee soul, then hopefully we can put worries like toxins and foreign bodies (which we' d want to address as soon as possible) lower on our list of concerns.
Just as an aside, if he isn't able to keep food down, then we'd expect a drop in feces (since no input means no output). So, I wouldn't be worried about that persay but it is another sign that we need to get him back on track as soon as possible.
So, if we can put those concerns lower on our list, then you can try and settle his stomach at home. First, you can try to settle his stomach by resting it by withholding food for 12 hours since the last vomit. He should have access to water at all times, but in small amounts since over drinking can induce vomiting as well. (f he does have a reasonable amount of water and cannot keep that down, then we'd have to consider having him seen sooner so that he can be treated with anti-vomiting/sickness medication by injection.)
If you haven’t seen further vomiting by that point, then I would advise giving him a small volume of a light/easily digestible diet. The chicken mince was a good idea but if he cannot keep that down then do consider trying boiled chicken with rice, boiled white fish and pasta scrambled eggs (made with water and not milk), or cottage cheese with rice. There are also veterinary prescription diets that can be used in cases of gastroenteritis, (ie Hill’s I/D or Royal Canin’s sensitivity).
You want to offer a small amount (1 tbsp) and if he keeps that down, a bit more can be offered about thirty minutes later. If no vomiting is seen, then you can increase the volume you are feeding. I usually advise that the diet be continued until the vomiting is settled, and that they are then slowly weaned back to their normal diet over a week.
If you are concerned that he is become dehydrated, then you do want to check her hydration. When checking a pet's hydration status, there are a few things we can test. One is whether the eyes appear sunken, if the gums are tacky instead of wet/moist, and whether the pet has a "skin tent" when you lift the skin. To see how to check these parameters for dehydration, you can find a wee video on this HERE. If he is showing those dehydration signs at this point, that is our cue to have him to the vet since oral rehydration can be difficult if they are vomiting.
If his vomiting has settled at this point, you can can offer or even syringe feed him pedialyte (pr pediatric rehydration solution). A typical maintenance rate for hydration in an animal is 48 milliliters per kilogram of body weight per day. This value will give you the total he needs for the day (though doesn’t take into account vomiting losses) and is a good starting point to give you an idea of his daily requirement. If he vomits you given pedialyte, I would discontinue this as a therapy. (since we don’t want more vomiting because of our intervention). As well, if his vomiting hasn't settled, then syringing won't be an option without anti-vomiting medication from the vet.
As well, you can consider addressing nausea as it will likely be the cause of his vomiting. There are a number of antacids that are available over the counter and pet friendly. I would advise only treating with one, but the two I tend to recommend are Pepcid (LINK) or Zantac (LINK). This medication of course shouldn’t be given without consulting your vet if he does have any pre-existing conditions or is on any other medications. Ideally, it should be given about 30 minutes before food to ease his upset gut signs.
If you initiate these treatments and do not see improvement over the next 24 hours (especially since this has been going on a few days) or he is appearing dehydrated, then I would advise following up with his vet so that they can address possible causes of vomiting and diarrhea. They can assess the diarrhea (and provided Salmonella or Campylobacteria are not suspected) then provide her with anti-diarrhea medication (ie Kaolin, Protexin, etc) to slow the diarrhea while you are trying to clear the infection (and the slowing will help give her compromised gut the chance to absorb those currently being lost nutrients and fluids). As well, since we find that animals with vomiting bugs struggle to keep medication down, the vet can given them by injection. And if they can get some antibiotics and anti-vomiting medication on board by this means, then we can usually settle their stomachs and help them get back to feeling like themselves.
I hope this information is helpful.
Please do let me know if you have any further questions.
If you have no further questions, feedback is always appreciated.
All the best,
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