Thank you for your patience. As you can probably imagine, there are quite a few things that could be causing these symptoms in your boy. Because he is an older dog, we have to consider everything from an acute gastroenteritis, to a toxicity or poisoning (hopefully there isn't anything he could have gotten in to around your home or yard), to an endocrine or internal organ issue. You are going to have to continue to keep a close eye on your boy if you can, and if his symptoms worsen at all, you will definitely need to get him seen by your local ER vet if you can. For now, you are best to with hold his food until the morning. From then you can start him on something bland and cooked, boneless, skinless chicken breast and boiled white rice is best for this. Make sure he has plenty of access to fresh water tonight and encourage him to drink.
It is great to hear his recent blood results were normal, so it is unlikely to be the further progression of an internal organ issue, however we can't rule out an acute organ problem or endocrine problem. Hopefully this is just a bit of gastroenteritis. As such, 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
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.
Best of luck with your boy. If he becomes any more lethargic, can't keep water down, or if any of the parameters mentioned above don't seem right, then play it safe and get him seen by your local ER vet tonight won't you. I hope all of the above makes sense? If you have more questions or if I can help in any other way, please do not hesitate to ask! If you would like to accept my answer, please press RATE OUR CONVERSATION (I am not compensated in any other way). Bonuses are always welcome. Thanks! I hope to work with you again soon!
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