From: Alison Skipper
Date: 2001-02-26 07:39:00 UTC
Subject: Re: rimadyl and its relatives
> From: "Dr. Bruce Williams" <williams@e...>
> Subject: Re: rimadyl
> Alison Skipper <skipper@b...> wrote:
> > For what it's worth, injectable Rimadyl is available in the UK.
> Our other main choice for pain relief in exotics would
> > be meloxicam, which has the advantage of being in a liquid
> formulation and so can be accurately given to very small animals; but
> I don't think meloxicam is available in the US, is it?
> Dear Dr. Skipper -
> Yes, it does not appear that Rimadyl injectable is available in the
> U.S., nor meloxicam
What about ketoprofen? That's another one licenced for dogs and cats in the UK.
> thank you for bringing me up to speed on the use of these two. Now I
> believe that the use of this drug in the earlier post was as an
> antipyretic (I am assuming as the ferret complaint was a respiratory
> tract infection.) Are you currently using it for antipyretic
> purposes or just for post-op pain relief?
I should say at the outset that I don't see very many ferrets as a vet - they tend to come in for neutering and possibly vaccination and then we frequently don't see them again. The exotics section of our practice is only about a year old, so most of our ferret patients are still very young. Maybe they are all just very healthy! (I don't think it's because they are dissatisfied and go elsewhere - the rabbits come back all too often!) Because I have relatively little practical experience with sick ferrets, I tend to extrapolate from feline medicine
as a starting point in matters of drug usage and so on. In cats, we are generally fairly happy to use these drugs for very short courses - such as one injection for an acute pyrexia following a cat bite abscess. In an elderly cat or one in generally poor health, we'd maybe drop the dose or think twice about whether we really needed to give the drug. We usually only have cats on these medications long-term if we really have to, if the quality of life is so improved by the drug that the risks seem justified (and the owner thinks so!) - for example
with severe arthritis. I don't remember using Rimadyl in ferrets for antipyretic purposes, but I don't think I'd have a problem with it if I knew the pyrexia had a simple cause such as a bite. Of course, if you are only using it as a single dose, you are going to avoid most of the problems with variation of pharmacokinetics between species. [For anyone who's blinded by science, I should explain. Aspirin is commonly thought to be toxic in cats. In man, to keep blood levels of aspirin up where you want them, in spite of the breakdown of the drug in
the body, you need to give the drug three times a day. Because cats break aspirin down way more slowly than people, you need only give the drug once every three days to a cat to achieve the same effective dose. If you don't know this, and give the dose to a cat as often as to a person, of course you will cause toxicity, because you are actually giving nine times the dose you need to. If you just give the drug every third day, it's not so toxic. If you are using an unlicenced drug in a species where it's not been studied, as we are when we give any
of these things to ferrets, then you are gambling on how fast the ferret's body will use up the drug, which may vary with the state of its liver etc anyway. But if you only give one single dose, it's not so dangerous, because even if it happens to take a week to break the drug down, you still aren't going to cause problems by adding extra doses before the body's ready.] You have to be especially careful with cats because, as strict carnivores, they lack lots of useful enzymes that break down toxins in less fussy species such as the dog. Dr
Williams, has any work been done on ferret enzymes? (other than the need for taurine).
> I must admit that I am probably from the old school - my training was
> that post-op pain relief was employed primarily following orthopedic
> procedures, but I don't generally consider it after routine abdominal
> procedures in ferrets. Is this a common practice in the UK to
> prescribe post-op pain relief after spays?
It is now, it wasn't ten years ago. Friends of mine who've had Caesars tell me they were very glad of the pain relief afterwards....:-) Various studies have been done and found that a single dose administered (preferably) at the start of surgery made a great difference to the patterns of behaviour in cats after surgery, which were much more active and therefore presumably felt better with pain relief. In rabbits, where there are huge problems caused by gut stasis if the patient doesn't start eating quickly after surgey, we find that it makes a real
difference to the recovery of normal gut function. I would think the same argument to encourage prompt feeding would apply to ferrets, with different reasons. Our practice uses routine post-op pain relief after anything that you would expect to cause significant pain - dental extractions in dogs and cats, abdominal surgery, lump removal, etc. One single dose is generally enough to make the animal a lot more comfortable, and I think owners are happier too! I don't know what drugs you would use for this purpose in the US, though.
Thanks again for this excellent list,
Alison Skipper MRCVS, UK