Towards the end I gave Jengo CBD oil. It isn't regulated whatsoever, so be careful about the supplier you choose. They all will usually say something like 99.9% pure CBD meaning they've extracted the THC leaving only a .1% trace amount. THC is what causes a high. What I found was that different suppliers seemed to have had different interpretations of what 99.9% pure meant. Do your research and find a supplier who knows what they are doing and is set up for repeatability batch after batch. A lab dedicated to dogs is even better.
I had no intention of getting Jengo stoned. He hated being drugged. But, I wanted to take the edge off of his pain and reduce his anxiety after he became partially blind following his stroke. IMO, CBD helped. But I watched him closely and only gave it to him if I felt he was having a bad day, which wasn't everyday.