White foam may be an issue of an empty stomach as with the yellow foam, however it can also point to one of several very serious and sometimes fatal issues.
The most common reasons for this include:
1) Blockage - When a dog swallows a non-food item of a chunk of food that is too large to safely pass, this can cause a partial or full blockage of the stomach and/or intestines. In some cases, the Beagle's first symptom may be vomiting of clear or white fluid - this can happen hours before any other clinical signs.
This brings to mind a dog that swallowed a roll of medical tape - unbeknown to the owners- that was tucked into a lower bathroom cabinet. Hours afterward, he vomited a puddle of clear fluid and seemed fine afterward. It was not until about 7 hours later that he showed other signs of distress.
Once taken to the vet, he needed emergency surgery to remove the tape, which had wound its way through the dog's intestines. It came very close to being a fatal situation.
Beagles have a high level of curiosity and are capable of mouthing and then swallowing all sorts of dangerous items. This includes Popsicle sticks, keys, rolls of floss, jewelry, shoe laces, pen caps, paper clips… If it can fit in his mouth, it can be swallowed. Keeping all of these sorts of object off the floor and from accessible places is prudent, not just for puppy care but for Beagles of all ages.
For this reason, if your Beagle vomits white or clear liquid with or without foam or mucus, you'll want to:
1- Search over the areas of the house that he had access to, looking for anything that was disturbed as a possible clue that he may have gotten into something that he should not have.
2- Closely watch him/her for any other developing signs or to see if he vomits a second time. Other red flags are: straining to eliminate a bowel movement, restlessness, acting panicked, whining, non-interest in eating or drinking, retreating, any signs of discomfort. In these cases, this warrants an immediate vet visit and this is considered an emergency.
2) Bloat - This exceedingly serious condition involves the stomach rotating or twisting in response to eating and exercising too closely together or eating too fast. However, if you see the warning signs of bloat, always seek help even if you do not believe that your Beagle did either of those two things.
Other symptoms include: Bloated abdomen, heavy panting, dry heaving, restlessness, pacing, not able to sit or lie comfortably, retreating, anxiousness and/or hunched over positioning.
This is considered an extreme emergency and a dog with bloat needs to be treated ASAP.
3) Other possible causes - There are many other possible causes that vary greatly. This includes kennel cough, diabetes, kidney disease, infection of the digestive tract, food allergies, hepatitis and even rabies.
Treatment - Since vomiting white foam can be a quick, acute case that is easily treated or it can point to a very serious issue that needs prompt professional intervention, it is important to keep a close eye on your Beagle.
If treatment at home is not working or if there are any other signs, you'll want to bring your dog to be examined right away.