Okay, here's what may be going on....
I think you're dog has had an upset belly for a couple of days. Sometimes, all you see is vomiting of a liquid if the dog's stomach is empty. If it was only moderately upset, she may have kept down some food, but vomited some as well. I think that seems to be what's happening here. The question is why, so that's something we'll need to try to determine. I will also give you a few things to assess on her to see if you should arrange a vet visit sooner rather than later.
It's difficult to tell what exactly has caused this. It's possible a virus could be to blame, particularly if there's a fever. Most viruses, you just need to wait them out for a few days, providing supportive care (like subcutaneous fluids and maple syrup for hypoglycemia) in the meantime. A new or unfamiliar food could also upset the stomach and cause these symptoms, as could a situation involving excess bile and stomach acids (this results in a yellowish liquid vomit, but it can also cause acid reflux which can cause gagging, discomfort and even a small amount of blood in severe cases).
I would also check your home and her toys very thoroughly. If she ate a non-food item, like a piece of a toy or some other item, like a meat bone or food wrapper from the trash can, it could absolutely cause the symptoms you're seeing. A toxin could trigger these problems as well, so I would check your entire home and yard for any signs that she got into something. I'll include a list below for common household toxins.
I would try her on some bland food so see if this will help to calm her system. Plain white rice and boiled hamburger, with the fat strained away, will work fine. Cottage cheese and plain boiled chicken with the skin removed can work too. Just start with a bite or two, and wait four hours. If she holds that down, give her two or three bites. Wait four more hours and continue the process untily you're at about 1/4 of her usual meal size.
And feed her this bland food three or four times a day for three full days. You should see an improvement by then. On the fourth day, you can begin to feed her normal dog food. But don't do this changeover suddenly. Mix four parts of the bland food with about one part normal dog food. On the fifth day, mix three parts bland food to two parts dog food and continue at this rate until she's on all dog food.
If she's continually vomiting you may have to let the stomach rest for 12-24 hours - no food during this time. During that time, you'll want to give pancake syrup - one large spoon for a small dog like yours, every 4-6 hours. This helps keep the blood sugar up. You can rub the syrup on her gums if she won't lick it.
For more info on hypoglycemia, visit: http://www.gopetsamerica.com/dog-health/hypoglycemia.aspx
To determine how dehydrated she is, look at the skin. If you pinch the skin between the shoulder blades up into a "tent", ideally, it should flatten right out. The more dehydrated she is, the longer it will take the skin to return to normal. So I would monitor this several times a day to ensure that she's not getting worse. If she's really dehydrated, a vet visit is in order. You can also feel her gums. They should be slick and wet. If they're sticky and not slick, then that's a sign of dehydration, which can be really bad because it starts the organs shutting down.
To help combat dehydration, you can add some unflavored pedialyte to her water in a 50/50 mix. If she won't go for that, offer some chicken or beef broth (no onions in the ingredients - they're toxic), a clear soup like chicken soup, or water with a bullion cube, as this will give it an appealing flavor. Sports drinks and clear juices (no citrus - the citric acid is upsetting to the tummy) can also be given - they're not the first choice, certainly - but mixed 50-50 with water, they will work - but only if she won't drink any of the other things, try these. We want her to drink more than usual because her body will need extra fluids to fight off whatever is causing this.
Now, this is important: we can't let her drink large amounts at once right now. Her stomach is upset and if she drinks too much at once, it will be even more upsetting. So let her have just a little bit at a time - every half-hour or so. Slowly, but surely is key here.
Also, a few things to check to monitor on your dog over the next couple of days. This will help you to assess her overall condition and if there is significant abnormalities, I would strongly recommend a vet visit asap:
A dog's normal rectal temperature is 100.5 to 102.5 degrees Fahrenheit. Ear temperature is slightly different: between 100.0 degrees and 103.0 degrees.
Checking the gums is an indicator of your dog's circulation. If there's internal bleeding, anemia, a disruption of normal blood flow, or serious illness, the gums will turn very pale, almost white in appearance. This means that the blood is not properly receiving oxygen or there's a loss of blood or red blood cells.
Normal gums will be bright pink to a pale pink. Abnormal gums are white with greyish, blue, or yellow.
Here is a link to a photo of normal gums: http://www.petmed.co.nz/images/gum_healthy.jpg
Here is a link to a couple of photos of pale gums: http://www.petplace.com/images-slide-show.aspx?id=3819&imageIndex=0 http://www.petplace.com/images-slide-show.aspx?id=728&imageIndex=0
I should note that I've seen perfectly healthy dogs with gums that are slightly paler than those pictured in the "normal gums" picture, but there's always a distinct pink tone.
For more information on checking your dog's gums, visit: http://www.ehow.com/how_3028_check-gums-dog.html
The normal heart rate varies depending on the size and age of the dog. A puppy has a heart rate of about 180 beats per minute. And adult dog will have a rate between 60-160 beats per minute. Small toy breeds can have normal heart rates of 180 beats per minute. The rule is the younger the dog, the faster the heart rate (for puppies). And the smaller the dog, the faster the heart rate. So I expect this little dog's heartrate will be near the 180 range.
Normal pulse is between 60 and 120.
Also, you can check capillary refill time. If you apply firm pressure to the gums, the area should turn pale and then quickly return back to normal (you can try this on your own skin to see what I mean). If there's no difference, or if your dog's gums take a long time to return back to normal, there could be a problem. The gums should return to normal in no less than one second and no more than two 1/2 seconds.
Signs of a really serious problem like bloat or an obstruction include: pale gums, blood in the vomit or feces, projectile vomiting, and no passage of matter through the digestive system (everything that he eats comes up, and nothing is coming out the other end either), a distended belly, and distress, like pacing, drooling and panting.
As promised, I'm also going to include some links to sites that list toxic plants food, and household items, as she could be exposed to a toxin that's triggering this episode of stomach upset. Plus, it's good info to have on-hand just in case. http://www.peteducation.com/article.cfm?cls=2&cat=1939&articleid=1030 http://www.cybercanine.com/toxicplants.htm http://www.peteducation.com/category_summary.cfm?cls=2&cat=1938
I have a couple of articles that I've written that you may find helpful. These articles are on vomiting in addition to diarrhea, which you may see in the next day or so - completely normal when the system is upset. http://dog-care.suite101.com/article.cfm/why_is_my_dog_vomitinghttp://dog-care.suite101.com/article.cfm/treat_your_dogs_vomiting_at_homehttp://dog-care.suite101.com/article.cfm/how_to_tell_if_your_dog_is_sickhttp://dog-care.suite101.com/article.cfm/diarrhea_causes_and_your_doghttp://dog-care.suite101.com/article.cfm/treating_a_dogs_diarrhea_at_home
So, give those tips a try and hopefully, she will be feeling better in no time! Just let me know if you have any additional questions!
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