I have two pups that take Metoclopramide for acid reflux as needed. It was designed for humans to combat nausea from chemo treatments and surgery. It has worked wonders on their reflux.
Vets used it regularly for reflux but when the more expensive meds came out, Vets mostly stopped using the cheaper tested Metoclopramide.
My dog takes two different anti-seizure prescription medicines. These are meds for humans that have epilepsy. Oh the irony.