@ Angela
It would be best to take your dog to a veterinarian for an examination and a diagnosis.
I would refrain from giving the dog antacids and other over the counter meds and supplements not intended for veterinary use. Unless the examining vet recommends.
What someone says worked for their dog may not be best for yours.
There are many reasons why a dog would exhibit the symptoms you described.
Many medications and supplements are not benign and have side effects.
Taking 3 or 4 different meds to treat the same condition is called polypharmacy, common among the elderly. Healthcare professionals discourage it.
Ps: Eating grass is not normal and could be an indication of GI upset among other things.
