All of a sudden high numbers on Lantus

TanyaAndProust

Member Since 2021
Hello,

My name is Tanya, and I have a cat named Proust who has been diagnosed with diabetes since November 2021 and asthma since a year earlier. Proust receives inhalation Flixotide twice daily, which was started at a 250 dosage but gradually lowered to 125, and insulin Glargin (Lantus) twice daily since November 2021, along with psyllium for constipation. We test his urine for glucose and ketones weekly. Food - Hills MD canned.

After starting insulin, Proust went into remission for half a year, but he needed to start insulinotherapy again after dental surgery. He has mostly been on 1.5 Units of insulin within normal healthy range of BG.

Recently, we noticed Proust's sugar levels had suddenly spiked to 19 mmol/L, which was much higher than the previous day's measurement of around 8. We tried to identify possible reasons for this, but we couldn't find any. We tried slowly increasing insulin, but it didn't work, so we took Proust to a veterinary clinic for lab results. The results showed that his globulins were a bit higher, and there was a very small number of bacteria in his urine. He was started on antibiotics, but his condition worsened. He lost his appetite and became less active, so we took him back to the clinic, where he was given IV fluids for a day and underwent additional tests such as USG and SDMA. However, no pathologies were found.

The veterinary clinic recommended that we gradually increase Proust's insulin dosage up to 5 units, monitor him closely, and observe any changes. Unfortunately, his sugar levels didn't improve even after increasing the insulin dosage to 5 units. IGF-1 results came back normal, meanwhile sugar rises up to 42 mmol\l, we’re increasing insulin, but nothing seems working…
Our vet would like to try rapid Prozinc insulin, but we don’t have it here in town.

*We’re located in Prague, Czech Republic (originally from Moscow, Russia; Proust was homeless back then in Moscow, rescued in 2015 along with other cats that live with us, all are healthy)

I’d appreciate any ideas on what to do next and how fast should I adjust insulin (our vet is cautious about the somogyi effect, she suggests to wait for 6 cycles each time we adjust the dose).

Thank you for reading this!

Spreadsheet
 
Hello and welcome. Thank you for rescuing Proust. Could you tell me what value the IGF-1 was? I'm glad to hear it was normal - I'm mostly just curious about the number. How long has he been back on insulin.

I cannot view the spreadsheet - which is the first thing I do. Could you change the permissions to viewable for all those with the link to it?

If you look over at our Lantus/Levemir/Biosimilars forum, we have a Sticky Note describing the two dosing methods here. Even the most aggressive one, Tight Regulation usually has you wait at least six cycles (three days) before increasing - providing appropriate testing is done.

One other thing, M/D is not a good food for a diabetic, its too high in carbs. Typically we suggest low carb food under 10%carbs, and the M/D is 13%, or what we consider medium carbs.
 
Thank you so much for the reply!
I’ve just updated permission settings to the spreadsheet file. Thanks for noticing that.
IGF-1 was 320 ng/ml (IDEXX lab in Liepzig).
Yes, usually we follow TR. But our numbers are crazy high now, and they get higher much faster than TR adjustments. Also it feels like, the higher the dose, the higher the numbers we get.

Yes, I will try to invent something else for him to eat with less carbs. He’s very stubborn about his food habits.
 
I thought the blood for the IGF-1 test would be sent to the UK from Liepzig, as it's so much closer. But in the UK, they measure IGF-1 in nmol/L. In the US, they measure in mg/dL.In the US, anything over 92 for IGF-1 is considered positive for acromegaly. It's over 1000 if tested in the UK. Could you double check with your vet where the blood was sent for the test.

This food list has a lot of diabetic friendly options available in Europe. UK Cat Food List

Thanks for fixing the permissions on the spreadsheet. You are increasing the dose too fast. On Feb 27th he had a very nice run of numbers under 100, when he was on 5 units. Then he bounced, but when you have green nadirs, you should hold the dose for 10 cycles to see where his blood sugar numbers went when the bounce was over. That can take up to six cycles to resolve.

Definition of what we call bouncing:
Bouncing is simply a natural reaction to what the cat's system perceives as a BG value that is "too low". "Too low" is relative. If a cat is used to BGs in the 200's, 300's, or higher for a long time, then even a BG that drops to 150 can trigger a "bounce". Bouncing can also be triggered if the blood glucose drops too low and/or too fast.The pancreas, then the liver, release glucogon, glycogen and counter-regulatory hormones. The end result is a dumping of "sugar" into the bloodstream to save the cat from going hypoglycemic from a perceived low. The action is often referred to as "liver panic" or "panicky liver". *Usually*, a bounce will clear kitty's system within 3 days (6 cycles).
Bouncing is a perfectly normal, though annoying (to us) behaviour.

I suspect you are on too high a dose at this point. I would go back to 5.0 units and shoot the same dose for at least 3 days, unless he goes under 50 (2.8).

You also seem to be changing the dose based somewhat on preshot numbers. With our dosing methods, we determine how to change the dose based on how low the dose takes the cat, not how high. That means shooting the same dose even if a lower preshot than you are used to. With Lantus, it gives flatter cycles if you shoot lower numbers.

And by the way, adding 1.5 to the Freestyle number does not get you "the real number". Are the numbers in your spreadsheet the Freestyle ones or with 1.5 added? We do find that in lower numbers, the Freestyle Libre tends to read lower, so it's good to have a handheld human meter to check when you see numbers that are lower.
 
@Wendy&Neko Thank you again for these thoughtful comments.
I’ve just double checked his IGF-1 results. It says “320 ng/ml” with reference “dwarf:<50 ng/ml
acromegaly: >665 ng/ml”

Just in case here’s the screenshot. Even though the letter says that the address is in Prague, the laboratory itself is situated in Germany, Leipzig (the closest branch to Prague). And all tests are performed there.

Thank you so much for that link with the UK’s food list, I was searching for it just now. I was so surprised and disappointed to learn that Hills MD wet is high carbo food and that all this “vet” “science” food is more like PR for our human brain…

Thank you very much for your advice on the spreadsheet and how to increase the doses. Now my husband and I are carefully reading and delving into it, for me it's all some kind of tricky mathematics and biochemistry, so I always ask my partner to double-check everything . :banghead:
Let's say we go back to 5.0 and sit on this dose for three days. If the sugar continues to rise during these days, then we start increasing the dose of insulin by 0.5? And another question, again, if we go back to 5.0, then how do we do that: sharply right away?i.e. we can shoot 5.0 units today?


And, yes, thanks for mentioning that Libre Freestyle can lower numbers. Btw, all numbers in our spreadsheet are raw numbers from Libre Freestyle sensor. I just noticed that Libre Freestyle differs in numbers with our human meter, but, I guess, that difference is not always linear, but anyway (for simplicity) I “created” a rule - if I want to get more real numbers, like those from the lab machine at the clinic, I’d have to add 1 or 1,5 to numbers from LibreFreestyle. (Everytime we do lab tests, we check the same drop of blood on our human meter and we scan Libre Sensor. Usually Libre Sensor is 1 or 1,5 lower than the lab machine, and our human meter is more or less always accurate as lab machine)
 
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The Idexx here (Canada) still sends the blood to Michigan State University in the US, the only place that does the IGF-1 test in North America. I presume Prague might do the same to send to the Royal Vet Clinic in London for the IGF-1 test. I know that's what happens in other clinics in Europe. Good to see the reference numbers, though they seem to have changed the acro positive indicator down. I had read that RVC was considering higher numbers close to 1000 as likely acromegaly.

Yes, you can start 5.0 units today. If test numbers are all high (above 300) after 3 days, go to 5.5 units. It's possible the 6 unit dose you shot the night of the 26th triggered the lower numbers of the AM of the 27th. The depot can influence several cycles after it was shot. Which is one of the reasons we find it easier to shoot the same consistent dose.

Are you testing for ketones at home? Anytime a cat is in higher numbers, and dose is reduced, it's a good practise.

It's great that you have the Libre, it means you won't miss any low numbers.
 
Yes, we test urine and blood for ketones at home. Thanks for reminding me to pay closer attention to that now :cat: And thank you again for answering all of my questions so quickly! :)
Whew..tonight we’re back to 5 units*fingers crossed* :nailbiting:
 
Proust who has been diagnosed with diabetes since November 2021 [ …] insulin Glargin (Lantus) twice daily since November 2021 […] After starting insulin, Proust went into remission for half a year
Just to clarify the timeline, when did Proust restart insulin?
 
Hello everyone,

First of all, I want to sincerely apologize for my long absence from the forum. Life has been incredibly demanding, and I’ve often found myself overwhelmed. I run a small home shelter for stray cats, many of whom are elderly or suffer from various illnesses. This has left me with little time or energy to participate here. At times, the emotional toll and sheer exhaustion led to periods of depression, making it even harder to engage. However, throughout this time, I’ve always kept in mind my desire to continue updating my thread and sharing our journey with you.

Now that I’ve managed to carve out some time, I’d like to share a significant development regarding my diabetic cat, which might be helpful for others managing similar situations.

**A Surprising Turnaround with Insulin Response**
Some time ago, my cat stopped responding to insulin altogether, even at higher doses. We were administering an increased dose of Lantus without any noticeable effect on his blood sugar levels. Then, almost miraculously, things changed. One day, his blood sugar dropped significantly—dangerously low, in fact—raising concerns about hypoglycemia.

From that point on, we began carefully reducing his insulin dosage. Over time, it became evident that he was once again responding to insulin. After much observation and investigation, I’ve developed a theory that might explain this phenomenon:

**The Role of Weight and Fat Metabolism**
It seems that my cat stops responding to insulin when he gains weight. My hypothesis is that during periods of weight gain, fat accumulates and insulin becomes "trapped" within the fat cells instead of being utilized by the body. Essentially, the insulin is present but inaccessible due to slowed metabolism and reduced fat usage—something that may be more pronounced in older cats with less active lifestyles.

To address this issue, we implemented a strategy focused on:
1. **Maintaining a Stable Weight:** Ensuring he doesn’t gain weight while keeping him well-fed and satisfied.
2. **Encouraging Fat Utilization:** Adjusting his diet and activity levels (as much as possible) to promote fat metabolism.

As soon as his body begins utilizing stored fat, it seems that the previously "trapped" insulin becomes active again, leading to sudden drops in blood sugar levels.

**Current Management and Stability**
At the moment, we’ve stabilized his condition after a lot of trial and error. His current insulin dosage ranges between 3 units and 3.75 units of Lantus depending on his weight fluctuations:
- **3 units:** When his weight is stable or slightly reduced.
- **3.25-3.5 units:** When there are minor signs of weight gain.
- **3.75 units:** When his blood sugar readings are higher due to potential fat accumulation.

His blood sugar levels now average between 6-7 mmol/L

**Dietary Adjustments**
We follow strict dietary guidelines based on recommendations from this forum and other trusted sources:
- **No dry food** whatsoever—it’s entirely unsuitable for diabetic cats.
- We use wet food with minimal carbohydrate content. In our case (we’re based in the Czech Republic), we’ve had excellent results with *Wild Freedom Senior* wet food for older cats. A friend who also manages a diabetic cat confirmed similar success with this brand.
- We tested nearly every diabetic-friendly brand available on Zooplus before settling on this one as the most effective for maintaining stable blood sugar levels.

**Challenges Along the Way**
During periods of high blood sugar, my cat experienced neuropathy in his paws—a common complication in diabetic cats (and humans). He would excessively lick his paws until they bled, which required bandaging and prolonged healing over several weeks. Thankfully, with better blood sugar control over the past year, this issue has fully resolved.
 
Another important aspect of managing diabetes was addressing his dental health issues. Over the past year, we performed several complex surgeries to remove rotten teeth from his mouth. These dental problems were likely contributing to chronic inflammation in his body, which can worsen diabetes management significantly
 
Thanks for the update,. I'm glad you've found something that works for Proust. Getting rid of any chronic infection/inflammation such as that dental, make a huge difference. We've seen cats go off of insulin as a result of dental and removing dry food. Without spreadsheet data, I cannot comment on the weight influence on his blood sugar, but I have seen papers talking about how important it is to get a diabetic to a good weight.

Should he get neuropathy again, methyl-B12 can be helpful.
 
Thanks for the update,. I'm glad you've found something that works for Proust. Getting rid of any chronic infection/inflammation such as that dental, make a huge difference. We've seen cats go off of insulin as a result of dental and removing dry food. Without spreadsheet data, I cannot comment on the weight influence on his blood sugar, but I have seen papers talking about how important it is to get a diabetic to a good weight.

Should he get neuropathy again, methyl-B12 can be helpful.

Thank you so much for your thoughtful reply – it truly warms my heart to see such people dedicating time and care to supporting diabetic cats and their guardians here. This kind of community effort brings real joy and meaning to life, especially when dealing with such challenging issues.

Just to clarify: we treated his teeth after stabilizing his blood sugar, and in our case, dental health didn’t directly impact his glucose levels. But I 100% agree oral hygiene matters! All our cats get yearly dental checkups, and we do surgical extractions the moment our vet recommends it.

About tracking data – I wish I could manage spreadsheets, but with our chaotic shelter life, we rely on the Glimp app on our phones. It logs daily blood glucose, insulin doses, behavior changes, and urine analysis etc..

Thank you for reminding me about methyl-B12:), I forgot to purchase some methyl-b12 for other cats :banghead:

Your kindness and expertise mean the world to us. Thanks again for being part of this journey! :bighug:
 
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