Now when we see haemorrhagic diarrhoea like this, we do have a few concerns. The most common reasons are viral infections (ie parvo, distemper, etc), bacterial infections (ie salmonella, campylobacter, etc), toxins, intestinal parasitism (not just the worms, but the protozoa like Giardia orCoccidia), and hemorrhagic gastroenteritis. And I have to warn you that for Zeus to be behind on vaccines at his age at this time of year means Parvo is a real worry here.
So, we do need to be careful here if we cannot soothe his gut. In regards ***** ***** that, provided you are sure he hasn’t ingested anything harmful (since those often require urgent care), then we can consider supportive care at this point. Of course if the bloody stools continue or are severe, then we'd want him seen sooner. Now to start, since he has some nausea signs there, we need to address those first. To do that, you can try Zeus with an OTC pet safe antacid [ie Pepcid (More Info/Dose @http://www.petplace.com/article/drug-library/library/over-the-counter/famotidine-pepcid), Zantac (More Info/Dose @ http://www.petplace.com/article/drug-library/library/over-the-counter/ranitidine-hcl-zantac)]. Whichever you choose, we’d give this 20 minutes before offering food to allow absorption. Of course, do double check with your vet if he has a known health issues or is on any medications you haven't mentioned. Though if he cannot keep it down due to nausea, that is usually a red flag that we need to bypass his mouth with injectable anti-vomiting medication from his vet.
After put him on small meals of a light like cooked white rice with boiled chicken, boiled white fish. scrambled eggs (made with water and not milk), or meat baby food (as long as its onion/garlic powder free). There are also vet diets that can be used (ie Hill’s I/D or Royal Canin’s sensitivity). The easily digestible diet will be better tolerated, absorbed by the compromised gut and should get some nutrients in and result in less diarrhoea. Fiber (ie canned pumpkin) and OTC probiotics (ie Benebac, Fortiflora) can be added to these meals to firm those loose stools quicker and support digestion. And this can be fed until he is settled and then we'd wean slowly back to your normal diet.
Since diarrhea can quickly dehydrate a dog, we need to keep an eye on his hydration. To make sure he's not getting dehydrated there are a few things we can test. One is whether his eyes appear sunken, if his gums are tacky instead of wet/moist, and whether he 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. ((http://www.ehow.com/video_12232503_dog-dehydrated.html) If you are seeing any signs of dehydration already, then you do want to have him seen by his vet before this becomes an additional issue for him.
If you are concerned that Zeus is become dehydrated, you can offer water, low sodium chicken broth, or Pedialyte. If he won't drink, we can gently syringe feed these at a dose of 48 milliliters per kilogram of body weight per day. On top of that, since this won't take into account diarrhea losses, we'd add this to that daily total. Of course, i he vomits when this is given, we would stop syringing (since we don’t want him vomiting because of our intervention).
Just to note, while it may be tempting to use anti-diarrheals here, this wouldn't be a diarrhea type to do so. The reason is because if this is caused by the aforementioned viruses or bacteria, slowing these feces can actually make them feel worse (as the virus can get a better "hold" in the gut and some bacteria secrete toxic substances that the body is trying to flush out with diarrhea). Therefore, light diets and keep Zeus hydrated are key here.
Overall, we need to tread with care for your lad. So, we can start the above now but if those signs linger or are severe; then we'd want his local vet involved. They will be able to assess him, test a stool sample for the above, and start broad spectrum antibiotics +/- fluids and symptomatic care to help settle this for him.
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