OK.
I asked about whether Fred might have received both buprenorphine and mirtazapine (appetite stimulant) because there is a moderate drug interaction between the two. We had a cat here earlier in the year who experienced an adverse reaction when simultaneously treated with both of the aforementioned drugs.
While it is not common to see pupil dilation as a side effect of buprenorphine treatment but if my experience with Saoirse is anything to go by it shouldn't have lasted as long as you observed in Fred. That Fred's pupils remained dilated for so long and also that he seemed so 'trippy' yesterday it made me wonder about whether any other medication might be exerting an influence to cause such marked, unusual clinical signs. Bearing in mind that Fred received a sedative I had a quick look online and found the following:
https://www.cuteness.com/article/medication-sedate-cat
From the above article:
Common Side Effects
No medications are free from side effects. Common consequences of sedatives in cats include vomiting, hypotension, increased appetite, anxiety, hallucinations, disorientation, diarrhea and restlessness.
Also, I found another article written by a vet about one particular sedative called acepromazine and in that article the author mentions that this particular drug can interact to potentiate the effect of pain meds. (Not saying that this drug is what Fred may have received, just giving you the link to an article which shows that sedative/pain med interaction is not unheard of.) Here's the link:
http://www.petmd.com/blogs/fullyvet...m-not-big-fan-when-it-comes-sedation-ace-6937
I wonder whether the bupe and the remnants of the sedative in Fred's system might have interacted? Also if the sedative Fred received yesterday does have appetite stimulation as part of its side effect profile that might explain his slightly greater interest in food last night. Speculating here, but I hope it will give you some ideas of what to ask your vet about.
Mogs
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