Peabody 1 month in on glargine with dose increases and no movement

[Peabody's mom Dorene]

Hi,
I've mentioned in a prior thread that the glargine I'm using was given to me by my vet as donated insulin. I did question the potency/expiration/prior storage to be told by the vet that yes there could be some chance of decrease effectiveness in switching vials but it (this particular insulin sample) has helped regulate other cats.

We have been moved up to 3 units a week ago and honestly before we move up to 4, I want a fresh vial of my own! I'm almost fearful to go up in units then switch to a fresh new vial because of my thoughts about this donated portion.

Question for those who have been doing this a while:
1. How long and how many increases before you see movement in BG? I know this is probably hard to answer as every cat is different.
2. Have you noticed for yourself a decrease of effectiveness of your glargine when you get further away from the expiration date or as the vial gets closer to being empty (ie. change in BG control) as I know due to cost most if not all are using it till its gone?

Thanks
Dorene & Peabody

 

[Nan & Amber (GA)]

Are you saying... your vet has been passing the same vial back and forth to several patients? Even if he's aliquotting out portions for each patient (so you don't need to worry about what the last customer did with the vial itself), it's definitely the case that insulin will lose effectiveness over time once opened. That's why most of us use the pens rather than the vials, they contain a smaller volume and are less likely to lose effectiveness before being used up. Glargine lasts much longer than the manufacturer says, you can usually get a good six months/year out of it with proper care, but still, with your vet's approach, I'd be concerned too!

That said, you are getting some movement in numbers. You've hit blue at a recent pre-shot, and there may have been at least a little movement yesterday when you got the midday test. Other than that, I'm afraid it's impossible to tell how well (or not) the insulin is working, without more tests between shots. He could be dipping down every single day (and night), then rising back up by pre-shot, and you'd never know it.

I'm sorry, I just don't think you can properly assess either the insulin or the dose at the moment. I'm a bit worried about the pace of dose increases in full units, especially without knowing what's going on mid-cycle. It's very possible that Peabody has skipped over his perfect dose already without you knowing. We usually change doses by 0.25U, for exactly this reason. It's surprising but true, that small a change can have a big effect in a cat's body!

I definitely wouldn't increase to 4U right now, especially if you start on fresh insulin. Wait and see how he does on the new insulin before making any moves, and do what you can to collect more data between shots. Anything you can get, a before-bed test or an out-the-door-to-work test, will be helpful in assessing the insulin/dose .

 

[Wendy&Neko]

Is it possible for you to get tests in between the two preshot tests at night? Even a test just before bed if it's 2 or more hours after the shot? We determine how to change the Lantus dose based on how low the dose takes the cat. We know for sure that 3 units takes Peabody to at least 101, if not lower, as that 101 was a preshot value. Many cats go lower at night so those before bed tests will give us an idea what is happening at night. Lantus generally produces curves downward between the preshots. The low points are not always at +6. It's truly ECID on what their typical low point or nadir is, and can vary between cycles with the same cat.

Could you take the next couple of days to try mixing up the testing and getting the odd night time test? We could find out that 3 units is too much, even with dodgy insulin.

 

[Peabody's mom Dorene]

Is it possible for you to get tests in between the two preshot tests at night? Even a test just before bed if it's 2 or more hours after the shot? We determine how to change the Lantus dose based on how low the dose takes the cat. We know for sure that 3 units takes Peabody to at least 101, if not lower, as that 101 was a preshot value. Many cats go lower at night so those before bed tests will give us an idea what is happening at night. Lantus generally produces curves downward between the preshots. The low points are not always at +6. It's truly ECID on what their typical low point or nadir is, and can vary between cycles with the same cat.

Could you take the next couple of days to try mixing up the testing and getting the odd night time test? We could find out that 3 units is too much, even with dodgy insulin.

Yes I can do more testing. Peabody's not a super fan but I feel like he's getting more used to me doing ear pokes. I'm going to pick up new insulin tomorrow from the pharmacy, I would have ordered from Canada but I really am anxious to see if fresh insulin would help or at least take the dodgy insulin out of the equation of why he's not moving too much and put my mind at rest about that.

 

[Wendy&Neko]

Make one change at a time. Your current insulin and current dose got him to very low blues. Let's see what he's really doing on this dose and insulin first, for a couple days. Then try the change in insulin for several days. If you are following SLGS for dosing as per your signature, those low blues mean you stay at this dose.