Hello, I am Dr. B, a licensed veterinarian and I would like to help you with Daisey today.
If Daisey is eating grass/dirt from the garden, then it is quite likely that she is experiencing nausea secondary to the agent that is causing her diarrhea. This is quite common since diarrhea affects the lower GI and nausea/vomiting affects the upper portion of the GI. That said, when we have a dog experiencing diarrhea and nausea, we do have a number of culprits to consider. This includes bacterial infection, viruses, parasites, dietary indiscretion, sensitive stomachs, toxins and foreign bodies.
Now if Daisey could have been exposed to toxins or may have ingested a non-edible object (ie trash, bones, toys, etc) that could get stuck in his GI, then we'd want her to be seen as soon as possible by her vet. If you are sure that she couldn't have ingested anything along these lines, then there are a few steps you can take to try and settle this at home (if the trigger is something benign like a dietary indiscretion, etc).
First, you can try her on a light/easily digestible diet. Examples of this would be boiled chicken with rice, boiled white fish with rice, 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). The easily digestible diet will be better tolerated and absorbed by the compromised gut and should get some nutrients in and result in less diarrhea. You can also feed this as small frequent meals to further decrease the volume of diarrhea she is producing and level of nausea she may be experiencing. 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. Since diarrhea can quickly dehydrate a small dog, so we need to keep an eye on her hydration. To check her hydration status to make sure they are not becoming dehydrated 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 she 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 you are seeing any signs of dehydration already, since she is so wee, then you do want to have her seen by the vet before this becomes an additional issue for her. (since it is often the dehydration that starts to tap their energy level, depresses them, and makes them feel ill)
If you are concerned that she is becoming dehydrated, you can try and encourage her to drink but offering fresh water or even low-sodium chicken broth. If she isn’t amenable to these, you can syringe feed her pedialyte. Pedialyte is nice (though aim for a flavorless one) because it will get some of those lost electrolytes back into her as well. A typical maintenance rate for hydration in an animal is 48mls per kilogram of weight a day. If you do give syringe pedialyte, this should obviously be divided up into multiple offerings through the day rather then all at once. This value will give you the total she needs for the day and is a good starting point to give you an idea of her daily requirement. (we aren’t calculating losses, so you can add an equivalent volume to match how much diarrhea she is producing). If she vomit when you have given pedialyte, then therapy should be discontinued (since we don’t want her vomiting because of our intervention).
Since she is showing a hint of nausea with her grass eating, you may consider covering her for upset stomach. There are also 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). Typically, this is given 30 minutes before food to be absorbed and in effect before offering food.
Overall, we need to make sure that Daisey isn't getting dehydrated and that we are supporting her with both fluid and nutrition through this bout of diarrhea. Therefore, I'd advise trying the above with her. If you do so and she isn't settling, shows blood in feces, or becomes dehydrated or depressed, then you'd want to follow up with her vet. They will be able to test her feces to identify the cause of diarrhea and be able to provide dog safe 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). Depending on their findings on exam and fecal testing, the vet will also be able to dispense the appropriate treatment (ie antibiotics, anti-parasitic drugs, etc) to clear the trigger for her diarrhea and get her back on track.
I hope this information is helpful.
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