Opioids

RE: Opioids

mariette asselbergs — Tue, 30 Aug 2016 14:47:13 GMT

I have been using intravenous paracetamol (in dogs only obviously) at 10 mg/kg BID or TID, and have been very impressed by it. Result immediately visible in the animal's demeanour/pain scale, and no depression or sedative effect as the opioids. Especially in a bit longer treatment. Can be used in combi with opioids or as alternative, and in combi with NSADs, or ketamine.

Mariette

RE: Opioids

Lara Brunori — Sun, 28 Aug 2016 17:05:59 GMT

Thanks a lot for your replies :) it's always great to hear different experiences. I was taught that mixing partial and full agonist was not ideal and the concept is still sticking in my mind. Having said that in the last ISFM webinar "Pain recognition and management", Jo Murrell mentioned the possibility of topping up bup with methadone. I've tried to find something in the literature but without success. Is it just another of those things that we just have to "believe" in?

RE: Opioids

David Mills — Sun, 28 Aug 2016 00:50:01 GMT

[quote user="Michael Woodhouse"]I know that is the theory, but a dog painful on buprenorphine/butorphanol that gets methadone seems less painful. [/quote]

Yep it's largely been discredited now. It would only hold if buprenorphine occupied all the mu receptors, which it doesn't, which means rescue analgesia with a full mu agonist works. It's an undergrad thing as said, which surprises me.

Butorphanol works on kappa receptors, so can be used alongside mu agonists without any interference.

I suspect re the OP there was insufficient absorption from the fenatnyl patch. I don't like them because, compared to injections, there are too many variables regarding absorption especially post-sx where the animal may be cold etc.

RE: Opioids

Michael Woodhouse — Sat, 27 Aug 2016 22:06:13 GMT

[quote user="Robert Falconer-Taylor"]You should not mix pure agonists with partial agonists like buprenorphine as the latter can knock the former of the receptor which is what you mean by competing.[/quote]

I know that is the theory, but a dog painful on buprenorphine/butorphanol that gets methadone seems less painful. I'm starting to think this is one of those undergrad theory things we all get taught that are not so clear cut in practice.

I would happily give methadone to the animal with a fentanyl patch. I think I would reach for ketamine first - I've loving that as an analgesic.

RE: Opioids

Robert FalconerTaylor — Sat, 27 Aug 2016 17:56:41 GMT

Both are pure mu receptor agonists so can be use together, net effect depends on occupancy of course. You should not mix pure agonists with partial agonists like buprenorphine as the latter can knock the former of the receptor which is what you mean by competing.