Question about Dexamethasone injectable, 2mg/ML

[Djones]

I am figuring out how to dose my gelding to nebulize him with Dex injectable mixed 1:1 with .9% saline, per the Flexineb instructions. I can’t get ahold of my vet (another story). anyway. I have a Flexineb, I have the correct saline, and I have a brand new bottle of Dex 2mg/ML

In reading over the literature for the Dex, the way “I” read it is that for every one ML of the injectable, there are two MG of Dex. If the dosing is 2.5 to 5 mg (as per the insert, shown here):

https://dailymed.nlm.nih.gov/dailymed/fda/fdaDrugXsl.cfm?setid=846a642a-8844-4a2a-ab13-fcfe9d5b655a&type=display)

then 5mg would be found in just 2.5 ML of Dexamethasone, but that seems wrong to me.

isn’t it by the horse’s weight? I am not trusting my memory on this. This seems to make a little more sense:

For the treatment of inflammatory or allergic conditions the following average doses
are advised. However the actual dose used should be determined by the severity of
the signs and the length of time for which they have been present.
Species Dosage
Horses, cattle, pigs 0.06 mg/kg body weight corresponding to 1.5 ml/50 kg
Dogs, cats 0.1 mg/kg body weight corresponding to 0.5 ml/10 kg

SOURCE:

Licence_VPA10791-004-001_04092017090359.pdf

YES I’m changing vets, ok. I know, I’m not happy either.

@Ghazzu, and others, help!

[Ghazzu]

Your math is correct, but I have no idea what the pharmacokinetics of inhaled dexamethasone are without searching the literature, so I can’t tell you what the dose should be.

It is also woth noting that the label doses of various drugs do not always match what is being prescribed for a particular condition.

[Ghazzu]

This paper used a nebulized dose of dexamethasone sodium phosphate of 5 mg/24 hours and apparently concluded it was reasonable.

[Djones]

@Ghazzu

This paper used a nebulized dose of dexamethasone sodium phosphate of 5 mg/24 hours and apparently concluded it was reasonable

Thank you!!! So he should get a volume of 2.5 ML of the 2mg/ML Dex and 2.5 ML of the saline.

I will leave my vet a message just to confirm he’s on board, and we’ll see if I get an answer

Again, a thousand thanks

[TheHunterKid90]

I hate that Dex is sold in 2mg and 4mg form. And you never know which you’ll get from the vet. always have to double check!

[DIR]

Can you share how your horse responds? I’ve been eyeing nebulizers, my Mare tolerates the Aservo inhaler but the $$$ add up quickly. If the dex dose could be that low, I’d be willing to try it.

[GoodTimes]

Yes, you always need to double check the dosage.
The dex that I have for nebulizing is 5 mg/ml. During bad flare ups I’ve used up to 10mg per day, weaning down to 5mg per day, than 2.5 mg per day, than every other day.

I live in Canada and our barn isn’t heated which means for 4-6 months it’s too cold to nebulize. I keep powdered dex at the barn so if the staff find him in a flare up they can just mix it in some grain or beet pulp and he’ll eat it. I keep the liquid/IV dex at home so it doesn’t freeze.

[Djones]

I’ll keep y’all posted. He was bad today.

VID_56801016_153935_933

[LCDR]

Older post, I know. Just FYI, you can order dexamethasone for veterinary use from Canada without a prescription. I did this to keep it stocked for my RAO gelding for many years, and the cost was significantly less than buying from my local vet.