Thank you for the prompt reply.
I would not be so worried about an interaction between any of the three drugs (clavamox, tramadol and denmarin) as all can safely be used together. However, the clavamox or the tramadol can have adverse effects at times on any given dog and certainly with the tramadol, it can be dose dependent. Tramadol can also cause a sense of dysphoria in some pets which is usually manifest is restlessness and seeming somewhat disoriented, but this is a bigger problem in cats than dogs. Clavamox can lead to GI upset in some pets which can cause panting and restlessness, but if he is eating and has normal stools, I doubt that is happening.
So the question is why is he panting and restless, especially at night. I would most highly consider discomfort as the cause and it could possibly be from the UTI (but should be better now) or the cancer plus/minus his arthritis. It sounds like a fast growing tumor and these can be painful so coupled with the pain of his arthritis, it may not be very well controlled with just the tramadol. The same holds true for his temperature. Even though 102.5 is still in the normal range, his increase may have been related to pain and inflammation.
Tramadol by itself is not the most effective pain control medication and you may need to get another medication on board as well. The concept of multi modal therapy (combining drugs) is very effective and if the Tramadol alone is not enough, adding another drug to the regime may be beneficial. This not only incorporates attacking the pain by a different mechanism of action, but the sometimes synergistic effect of the two drugs together allows you the keep the doses of both down, avoiding potential side effects. Two of the oral drugs I keep in mind to add for pain are a non-steroidal anti-inflammatory (like Rimadyl) and Gabapentin. Your vet will know if either is an appropriate choice for your dog if you need to provide extra pain relief now or on a more chronic level in the future. I would start there and see if the restlessness improves.
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