[anonymous]

I imagine it is similar to Rimadyl a very effective NSAID. Some dogs do very well on NSAIDs for pain management and as an anti-inflammatory.
However some dogs (not all) experience gastrointestinal side effects, not always right away.
I had a senior small breed that did very well on it for several months and then developed diarrhea, so he could no longer tolerate it.
So, I would say keep an eye on him and if he develops GI symptoms, don’t assume it’s GI related, I would hold the med and head right back to the vet.

https://www.fda.gov/AnimalVeterinary/NewsEvents/CVMUpdates/ucm491552.htm
March 21, 2016
The U.S. Food and Drug Administration today announced the approval of Galliprant (grapiprant tablets), a new animal drug intended to control pain and inflammation associated with osteoarthritis in dogs.
Osteoarthritis (OA) is a condition where cartilage – the protective material that cushions a joint – breaks down over time, causing the bones to rub against each other. This rubbing can permanently damage the joint and cause pain, inflammation, and lameness. Older and overweight dogs are at a higher risk of developing OA.
A new treatment option for dogs with OA, Galliprant is a prostaglandin E2 (PGE2) EP4 receptor antagonist; a non-cyclooxygenase inhibiting, non steroidal anti-inflammatory drug (NSAID). All NSAIDs carry certain risks, including vomiting, diarrhea, not eating/eating less, and lethargy. These drugs must be prescribed by a licensed veterinarian, because professional expertise is needed to diagnose and provide guidance in the control of OA pain.
Other NSAIDs that are FDA-approved for use in dogs include deracoxib (Deramaxx), carprofen (Rimadyl, Novocox, Carprieve, Quellin, Carprofen), meloxicam (Metacam, Loxicom, Orocam, Meloxidyl, Meloxicam), and firocoxib (Previcox).
The application for Galliprant is sponsored by Aratana Therapeutics