You can also use an air bubble to help it mix. Let the bubble go from top to bottom, and then invert the syringe and let it go the other way. Do that a few times.
3 Likes
Just a few things to note:
1.) Humulin NPH can be mixed with Humulin R, so as far as it’s ability to mix, though it is not officially supported, it should work without issue, BUT they haven’t tested to say that with certainty.
2.) The biggest difference between NPH & Lantus or Tresiba is that NPH is what used to be used for basal, it’s biggest negative was that it has “Peaks” where you HAVE to eat or go Hypo. Lantus was the big game changer to that, because Lantus lasts 24 (technically supposed to be 36 I believe) hours WITH NOT “PEAKS”. So the BIGGEST benefit to it is that if the animal is having issues with lows that could be in part due to those peaks, which require eating at specific times. When I was a kid & used R/NPH I often had issues with lows at those peaks, even though I’ve always needed a lot more insulin than is average. Now the negative is that, in the US at least, Lantus requires a Rx & costs a LOT more. In the US the only humans that use NPH would be those who are buying over the counter because it can be had for like $20/vial & doesn’t require a prescription.
3.) Now as far as mixing insulin you can’t mix Lantus with NPH or other Humulin Insulins like R or 70/30. So Lantus would NOT work with your diluent. But like how 70/30 is a mix of NPH & R that mixes together & maintains both in balance so long as you properly shake/roll the vial until it is evenly cloudy. Likewise a mix of your diluent would be the same. My suggestion would be to reuse an old vial of your NPH after it is empty to be your mixed vial, just make sure to label it & keep in refrigerated & that it doesn’t freeze. Essentially what your diluent is doing is making it so that when you draw up 1 vial only part of it is the NPH (so long as properly mixed like with 70/30). The diluent is something that can safely take up space with Humulin R but has no Insulin in it, essentially the stuff that’s cut in half when you have a 200u/ml vial instead of the standard 100u/ml vials. & while the increasing of the concentration is tricky, the opposite should be more straightforward. But, & this I think needs to be stressed, thorough mixing is ESSENTIAL to getting consistent doses. As such I’d say mixing in syringe is a recipe for disaster as no matter how you go about mixing you will never be able to get a truly balanced mix if done in a syringe.
3 Likes
Made me laugh with this one.
Once I was done laughing I started wondering… did you dilute in a syringe? Could it be mixing in a syringe didn’t allow for precise dilution and you got more insulin than intended? Or did you just happen to have some very good chocolate around…?
2 Likes
Would this mean injecting once a day?
The current protocol for the dog is 2 meals and 2 injections.
(He also gets lots of honey in between cause of the hypo. Thinking of renaming him Winnie the Pooch…)
1 Like
So that would be a trial and error thing. It would appear that the vet is taking advantage of the peak with NPH to cover the food, you might be able to cover with a bit higher Lantus dose, or if the meal is low enough carb then you wouldn’t need to cover with additional insulin. See the graphs below. Are you timing the meals to coincide with the peak action of NPH currently? i.e. 4 hours post injection?
1 Like
No. The directions I have are to feed him and inject after the meal. I think this is the standard for dogs.
And indeed what happens with NPH is about 4 hours after the meal his sugar drops too low. If I try to avoid that and inject less the sugar levels remain sky high.
That’s what had me looking into diluting. Trying to reach the optimal amount at a very low dose. And from what I’m learning here, could be NPH is just not the right insulin for him.
1 Like
Mixing in a vial is better.
But I do think it can mix well in a syringe too. You can roll it and use the bubble to go up and down and it will mix up fine.
But if you have spare vials, that would be the easier way to go.
It mixed fine. I took 5 units. I can tell the difference between 5 and 10, there was no question about it.
The reason I trended low yesterday is because I did not turn off my pump basal. So the NPH was on top of the pump. But if it had been 10 units instead of 5, it would’ve been very obvious to me.
3 Likes
I told friends that someone I don’t know was willing to test diluting and injecting insulin in order to help my dog. You now have a bunch of fans in Israel. In awe of your generosity.
4 Likes
Thank you!
Dogs are my favorite people. 
5 Likes
I’ve been so careful not to shake the insulin vial, not to freeze it, to return it to the fridge quickly, and to replace it after 28 days…
I understand now that I can relax and stop doing all of that.
Definitely going to try cursing at the vials instead 
3 Likes
Thanks for everything you shared.
Definitely easier for me to mix in a vial. And as I’m giving tiny doses it’s especially important that the mixing is thorough.
I just don’t know how long a diluted vial would be good for.
I might just dilute in a vial and make a new batch every day.
How many times do you reuse a vial?
And do you do anything to clean it before reusing it?
1 Like
I bought sterile vials, and I also have old insulin vials.
Do you reuse those for dilutions?
And what would be your estimate, how long do you think a diluted vial would be good for?
2 Likes
Nora, everyone here uses vials multiple times. If you store your diluted vial in the fridge, probably a week, maybe a month. The only way to know is to test, do you get blood sugar readings from your dog, or just observe the lows from physical behaviors? The easiest way to know would be to use it until it no longer controls your dogs blood sugar based on meter readings.
2 Likes
Diluting in the sterile EMPTY vials is safer! Because you can never get all the insulin out of an old insulin vial. That means your dilution % would never be exact if you use an old insulin vial.
So put both the diluent and the NPH in an unused (empty) vial.
Once you have settled on a percentage of dilution (for example, if you figure out your dog needs 30% dilution), then you can reuse the same vial for that same percentage.
What I mean to say is that mixing 30% dilution into a vial that previously held 30%, that’s fine. But mixing 30% into a vial that previously held 50% dilution is NOT fine. Because you can never fully empty any syringe, so your dilution is never exact if you switch percentages in the same vial.
Sorry, hope that was not confusing. Does that all make sense?
So you need to figure out how much dilution to do. If 1/2 unit is too much for your dog, maybe you want to try 0.30 units next? So you would do 3 units of NPH and 7 units of diluent in the vial, and label your vial. And remember, now you would do 1 FULL unit of that mix, which would be only 0.30 units of insulin.
I have used diluted rapid insulin a long time, like months! But there may be some degradation, who knows. It’s hard to be completely certain.
If you dilute it in small batches it won’t stay in the vial too long compared to a big batch. So that might be the safe way to go.
Maybe dilute enough to last 2 weeks or so. I think that’s a safe time-frame.
2 Likes
I didn’t have readings this week (3 failed attempts of attaching freestyle libre. Gave him a break). Hopefully we’ll get one attached tomorrow and then I’ll do just that. Dilute, inject and get readings.
If vials can be reused that makes it even easier.
1 Like
Not confusing at all. Made perfect sense.
Got it. I’ll try different dilution percentages, see what works best for him, and I’ll make sure to label the vials.
Have I thanked you yet? 
2 Likes
Once you get the insulin dialed in, you may want to play a bit with the meal timing. That way, if you inject insulin then feed 1 or 2 hours later you might get a better response. I just don’t know enough about dog digestion to be more helpful here. With people, we try to get the digestion to match the insulin action curve. But of course everyone’s digestion is a bit different which requires much trial and error.
2 Likes
28 days - same as the original vial. You are working very carefully in a controlled environment with conditions that are sterile apart from the air you have to inject into the original vial to get the stuff out.
When I was young I injected from those vials in conditions that were certainly not anywhere near as sterile and without anywhere near the care you take; these are the real conditions those vials and their contents are required to deal with. The manufacturers are cautious; they have to deal with people like the younger me.
3 Likes
@jbowler Do you really replace your insulin vials every 28 days? I’ve been taking insulin for 42 years and have always just used a vial until it’s empty. Am I doing a bad thing? 
4 Likes
@Nora What a sweet heart you have to spend so much time and energy on making sure your dog is cared for with top-notch insulin protocols! I admire you greatly.
4 Likes