Thank you for your patience. Your question came through to me just a few moments ago, so apologies for the delay. These symptoms are definitely a worry and as you can probably imagine, there are a number of possible causes for this vomiting. Hopefully Otis is up to date deworming treatments and vaccinations. Potential causes for his symptoms include anything from acute gastroenteritis, to an endocrine issue, or even an internal organ issue. Whatever the case, the fact he has vomited up what appears to be blood is definitely a concern, and you will need to keep a very close eye on him. With hold any food for now until the morning, but do encourage him to drink plenty of water for now.
Otis may need to be seen by an ER vet if this vomiting continues this morning. For now, please keep a close eye on his mucus membranes, capillary refill time and respiratory rate as follows:
Mucus membranes - flip his lip and look at the color of his gums. They should maintain a nice salmon pink color. Get him to the emergency Vet if they appear white or very pale pink, or if they are a dark deep red color.
Capillary Refill time - this measures blood perfusion and test this by putting your thumb on his gum to apply pressure. After you release your thumb you will see the gum blanch. Capillary refill time is the amount of time it takes (in seconds) for the gum to return to a healthy pink color from the blanched white color. If 2 seconds or less don't worry - if it is taking significantly more time, again - off to the emergency Vet.
Respiratory Rate - if he is continuously panting throughout the night, this is a sign of shock and or pain and a signal for a trip to the emergency Vet.
For now, you may also want to try him with a little pepcid. The typical dose for this type of situation is 0.25mg per pound of body weight up to twice daily. You can read more about the use of Pepcid in dogs online here: http://www.petplace.com/article/drug-library/library/over-the-counter/famotidine-pepcid
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