Hello again Debbie and thanks for waiting.
Sorry to hear Chevy is unwell, however I have worked out an answer for you below ...
Going on my past experience I would very much doubt if this is related in any way to the Gentamycin spray, as this is an antibiotic it would rarely have this effect, dogs can start to vomit for a variety of reasons which are sometimes hard to pin down. That said that there are a number of home remedies for vomiting in the dog which some owners try, these can often work well for uncomplicated cases where for example a dog has eaten something he should not have out in the yard, or had some unaccustomed rich foodstuff, or has somehow acquired a minor tummy bug of some sort. Here are some examples.
1. I am aware that some owners use Pepto-Bismol to treat their dogs with gastro-enteritis and report success. Here is a link to a web page which has all the information you might need including dose rates : LINK
2. Some owners try and control the situation with diet alone before they try anything else. This is logical and often works, the basis of this is to give the intestinal tract a complete rest and then bring it back slowly to function, resting the alimentary tract is the critical factor. It would go something like this ...
A. Starve him for 24 hours but make sure he has access to water.
B. The next day feed him four or five small light meals in the day. These meals should be the likes of chicken, fish, scrambled egg etc. with a little rice.
C. If he picks up on this diet gradually reintroduce his normal diet over the next few days.
3. Live yogurt added to the food can often help. Some gastro-enteritis situations are caused by an imbalance in the bacteria in your dog's gut. Live yogurt is full of " good " bacteria and will seed them into your dog's intestinal tract and restore the balance. A couple of tablespoons twice a day should be fine for a dog of your one's size.
Of course if any of the above does not quickly start to work or if Chevy deteriorates further in any way you should have your vet check him over just to be on the safe side.
I hope I have covered your question fully enough but if you would like further clarification or to talk things over a bit more then I will be on-line for the next hour or so and I will be more than pleased to continue working with you.
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