My Wally was on Marbocyl tablets. I used to crush the tablet, mix with a little water and syringe it in. To crush the tablet I put it in a little lid and used the end of a teaspoon handle, like a mini pestle and mortar. The teaspoon had a rounded handle with a flat end. I did the same for Daisy's Tramadol tablets, although they were much harder to crush.
Wally started off with injectible Marbocyl, but the injections can sometimes sting, due to the carrier substance I think. It did sting Wally and it upset him. He couldn't tolerate any upset or stress as it triggered mouth breathing, so he was put on the tablet form instead.