Gave a subcut injection IV... can anyone explain..

RE: Gave a subcut injection IV... can anyone explain..

Andrea Tarr — Tue, 20 Nov 2018 14:12:48 GMT

Hello

As you know Baytril (enrofloxacin) is only licensed for use IM or SC.

It is sometimes used IV in cases of severe sepsis (BSAVA Formulary), but if used in this way it should be diluted x10 with saline and infused slowly over 35-45 minutes. This is because the Baytril formulation contains potassium, and fast injection of potassium salts can affect heart rhythm.

Enrofloxacin would work if injected IV. Doing it this way would make sure you got antibacterial levels as quickly as possible (which you might want in cases such as severe sepsis - this would be uniicensed use). In other cases, it is sufficient and safer to give it IM or SC. In the case of enrofloxacin, the drug needs to come into contact with the bacteria, not interact with body receptors.

The choice of route for a drug depends on various factors - e.g. where the drug needs to get to, how well it is absorbed, whether you want to high levels of the drug in the body quickly, or instead want a longer more sustained effect.

In this case, the enrofloxacin would have had an antibacterial effect, and I assume from what you say that there were no adverse effects. So no harm done.

Andrea Tarr

Founder, www.veterinaryprescriber.rg https://cpd.veterinaryprescriber.org

RE: Gave a subcut injection IV... can anyone explain..

ashbee91 — Wed, 14 Nov 2018 15:23:18 GMT

Thanks guys. I understand that some medication can't be given IV due to reactions ie drop in BP/ anaphylaxis .. I just couldn't get my head around why when they were saying it doesn't work IV they still thought the patient was covered by it.

Perhaps the RVN that spoke to the vet got the wrong end of the stick, maybe the vet said it shouldnt be given IV and she's assumed that its because it doesnt work rather than because its not liscenced.. who knows!

But thanks for clearing that up... she couldn't understand what I was saying and its been bugging me since :)

RE: Gave a subcut injection IV... can anyone explain..

apache — Tue, 13 Nov 2018 22:33:24 GMT

[quote user="ashbee91"]The vet said that it doesn't work IV[/quote]

Your vet is wrong! Have used it lots of times IV in cows. Works just fine even though off licence. Perfectly safe and perhaps even more effective for reasons I can explain if you want.

RE: Gave a subcut injection IV... can anyone explain..

Alison Clare Hickman — Tue, 13 Nov 2018 21:06:07 GMT

Hello,

The drug is not licensed for IV administration... See NOAH http://www.noahcompendium.co.uk/?id=-446342

But that doesn't mean this particular one Baytril (enrofloxacin) has no action in the body if given IV. The receptors for the drug will still receive it but more quickly than SC or IM (or oral in its oral presentation). From my (reasonably quick) research tonight there are instances of IV enrofloxacin administration in dogs... See

https://www.msdmanuals.com/en-gb/professional/clinical-pharmacology/pharmacodynamics/overview-of-pharmacodynamics

You can see in the above article they were comparing speed, efficacy and concentrations between an oral and IV administration.

So, I extrapolate from this article that IV administration of the drug reaches the same receptors as those from other administration routes (just at a different speed) and that is why you were prevented from redosing your patient. You would have overdosed them.

Some drugs cause problems (from minor to major to fatal) if administered by the wrong route so clearly much care must be taken to select the correct route. An example of this is IV administration of Pethidine in the dog. It can cause an anaphylatic reaction. The drug would still work as an analgesic if given IV but as it has an adverse reaction when administered, it is not given by this route (normally).

I haven't been able to find a reason why enrofloxacin shouldn't be administered IV. Anyone??

I am sure your vet is aware of the altered pharmacodynamic of the Baytril (enrofloxacin) in the patient and has taken steps to alleviate or complement it's action.

Hope this helps.