Metoclopramide, also known as Reglan, is commonly used as an anti-emetic. It is, indeed, a motility drug. Essentially, it acts to stimulate the stomach, duodenem, and other organs of the GI tract to push food out more quickly. Or, in the case of someone with gastroparesis, at all.

This is the drug I was initially prescribed when I was diagnosed with my gastroparesis. However, it was not a good fit in my case as it can cross the blood brain barrier and cause side effects in a small number of people. For me, it somehow interfered with my mental abilities making me slow and stupid. I was clearly drugged while on it.

I have no idea what effect it might have on a pet, though.