Sorry to hear about your recent diagnosis. It is always tricky when dealing with co-morbidities.

Has your vet suggested monitoring the liver parameters and using liver support to assess its response? My dog had a liver tumour which was excised along with 2/3of her liver. She amazingly expanded her remaining lobe and returned to near normal function – so the recent issue may not be a forever problem and worth performing repeated blood tests including those looking at liver function, as well as monitoring thirst, weight etc.

Giving advice about other meds is almost impossible and discourage by the Veterinary Medicines Directorate and Royal College. However I can say you still have lots of options.

First off I would start tracking level of pain with a pain assessment tool as you may not need as much pain relief as you are expecting.

Then I would try to clarify what kind of pain your dog is experiencing. Are they suffering long background musculoskeletal pain worse on weight bearing, or is it short sharp intermittent episodes. I would want to know how well they cope with the pain or whether you think it is impacting them emotionally etc. Is it worse at night or during the day…

I would then discuss your findings and options with your vet. And if they are not able to support you can chat to a pain practitioner or a referral vet at once of the referral centres.

I would also not overlook the non therapeutic interventions like massage, exercise, heat etc

I hope that helps,
Hannah