From Dr Mike's Vet info
" I have researched this question in the past without finding a really good answer
for what causes vomiting in the morning (mostly) in some dogs or for what
to do about it.
The prevailing opinion is that many of the dogs that exhibit this clinical
sign have inflammatory bowel disease (IBD) or some other condition that
causes a decrease in gastric mobility. This may lead to gastric reflux when
the dog first gets up or when there is excitement, as your vets have
suggested. The gastric reflux causes some dogs to vomit. It is highly
likely that there are a number of causes of this behavior but this theory
does account for a big portion of the affected dogs, I suspect.
When possible, confirming or ruling our a diagnosis of IBD through food
trials, intestinal biopsy, ultrasonagraphy or other means can be helpful in
pointing out a direction for treatment efforts. In many instances, it is
not possible for clients to pursue the diagnostic testing right at the time
of the visit to their vet, though. Because of this, there is a tendency to
try treatment to see if it is possible to aid the pet without having a
specific diagnosis. The most common treatments are histamine (H2) blockers
like cimetidine (Tagamet Rx) or famotidine (Pepcid AC tm), feeding small
meals just before bed and using motility modifying medications like
metoclopramide (Reglan Rx). These things sometimes work to control the
problem and if no futher signs develop it is reasonable to continue
treatment prophylactically without a firm diagnosis, at least in my opinion.
If these things don't help, or are only partially effective, it would be
better to continue to work towards a diagnosis using one or more of the
tests mentioned above.
Good luck with this.
Mike Richards, DVM
If it were me I would start with the late night snack routine worked for us and many others without having to resort to medication.