Dosing Advice Based on Curve

Hi guys. Okay, so Lola has been on ProZinc insulin, 1 unit every 12 hours, for 2 weeks now. I’ve just done a glucose curve using a Freestyle InsuLinx meter, which I’ve converted into mg/dL in addition to showing mmol/L.

My spreadsheet is out of date, but I’ll update it later when I am home. Anyways, how do the curves look? For reference, on an average day, her AMPS and PMPS are both between 11 and 13 mmol/L, or 216 and 252 mg/dL. She started on the curve at 13.4 mmol/L (241 mg/dL), and nadir was 9.7 mmol/L (175 mg/dL).

She’s on 1 unit of ProZinc insulin every 12 hours. I’m going to talk to the vet, but would you guys recommend a dose adjustment?

Edit: To clarify, the numbers on the x axis represent hours since insulin, where I did her AMPS and insulin shot at 7:30 AM.

Edit #2: Lola also takes 3.75 mg prednisolone at the time of her morning insulin, so that may affect the curve, right?

 

Curve analysis:

• PSs aren't bad
• nadir around +6 - expected for ProZinc
• <50% drop at nadir suggesting that a small dose increase is in order
• duration is about 10 hours on this particular day.

Yes, her pred might affect the curve. If you can add data from PMPS until as late as you can manage on a day off that should tell the other half of the story. This daytime curve tells me that you could try 1.25 u at least during the day. It's possible that 1 u is enough at night when the pred is waning. Does it have a long half life?

FYI - most vets will roll their eyes at the idea of a quarter unit.

 

I agree with Kris. Based on this curve, I would increase to 1.25.

 

Thanks for the advice! In cats, prednisolone has a serum half-life of approximately 30 minutes, so it’s gone quite quickly. It’s known that prednisolone induces insulin resistance, but the kinetics of that/how long the resistance lasts after administration is unknown. In theory, it wouldn’t affect a PM curve, but it could affect an AM curve.

I will do a few spot checks in the PM on Saturday night. Nadir looks like it’s at about 6 hours, so if I give the shot at 7:00 PM, does it make sense to do a couple spot checks at 11:00 PM and 1:00 AM?

Haha, yeah. I’m thinking I’ll use a permanent marker to pre-mark the 1.25 spot on the syringe for more accuracy. What do you do to accurately estimate that amount?

 

I'd just eyeball it half way between the 1 u and 1.5 u marks. Consistency dose to dose is more important than absolute accuracy. Some people use calipers to ensure repeatability but I don't.

 

Yes, those would help.

 

Unfortunately, my syringes have marks in 1 unit increments. Where do you get syringes with 0.5 unit increments?

 

I order mine from ADWDiabetes.com: https://www.adwdiabetes.com/product/18553/ulticare-u40-pet-29g-3-10cc-1-2in-half-unit

 

I realize I'm a week late to the party here, but you can also order u100 syringes and then use this conversion chart. That way you can make smaller adjustments with greater accuracy.

Conversion chart: http://www.felinediabetes.com/insulin-conversions.htm

The u100 syringes are available at any pharmacy. WalMart has them for about $13, or you can order from ADW.