Dog Vomits After Drinking, What Could It Be?

If it's happening right after exercise or excitement chances are she's gulping a lot of air down with the water and just needs to calm down/cool down a bit before being offered a drink. But given that you've stated "for 3 days off and on", I'm guessing that's not the case so I'll offer another opinion.

The obvious answer is... Your dog in nauseous, and so when she drinks it upsets her tummy that much more and gives her something else to throw up. As to why her stomach is upset... The possibilities are varied and many. The easy/safe answer is... Take her to the vet, always good to err on the side of caution if you can afford to. The answer I think you're looking for is... It's probably just simple gastritis caused by something she ate that she shouldn't have, or a minor virus, and chances are she'll be just fine in a few days. If she's acting fairly normally aside from the vomiting you can give her Pepcid for a couple of days to help settle her stomach. The typical dose administered is 0.25 to 0.5 mg per pound (0.5 to 1.0 mg/kg) every 12 to 24 hours. If however, there is blood in the vomit or your dog is in obvious abdominal pain, or seems particularly depressed or weak, has a fever, or retches unproductively, you need to seek professional help... Hope she's doing better soon.

If you are giving cold water to your dog then it's not good for smaller breeds because they have bad respiratory systems such as bulldogs and they vomit.

Other reason could be:

Dogs usually drink too much of water very fast, if given to them after a long time frame, and the food/water comes right back up. So the water should always be there for him, in that manner he will not drink all of it at once.

My dog never vomited back water "until she had a "difficult" tooth extraction during cleaning". This all calculated to 3 hours of anesthesia administered by a tube in down her throat. Today she has been diagnosed with a partially collapsed trachia, which I am told is becoming more and more common place today. My personal diagnosis of this situation is that anesthesia administered for cleanings / extractions via a tube is causing these "partially collapsed esophagus".

If at all nothing appears from the outside then it could be a minor issue. Some of the minor causes of vomiting can be stomach or intestinal viruses, stomach or intestinal parasites, indiscretions such as eating garbage.

She doesn't seem ill otherwise and is vomiting less often about every 12 hrs or more. She still has a good appetite but the food isn't getting digested unless she eats just a small amt. Anyway we are taking hr to the vet today so we shall see. thanks for your answer!