Transitioning acro cat Mister from ProZinc to Levemir

Previous thread(s) here: https://felinediabetes.com/FDMB/threads/mister-has-very-high-igf-1-what-are-my-options.262196/

Mister's insulin resistance has never been worse, despite an increasingly high dose of ProZinc. He has IAA and Acromegaly (or Hypersomatotropism/HST). I ordered 15 pens of Levemir from Mark's Pharmacy in Canada that has just arrived.

First questions that come to mind are:

• What needles should I order given he is a high dose cat? Do I even need to seek out syringes with half unit markings? What happened to ReliOn U-100 syringes, I don't see them anywhere on Walmart's site?
  
• What initial dosing of Levemir should I go with?
• Should I even switch to Levemir so quickly after starting Cabergoline? I started him on Cabergoline compounded to 200μ/kg with 0.37ml EOD dosing on 05/06/22.

I'll be studying this sticky in the coming days: https://www.felinediabetes.com/FDMB...info-proper-handling-drawing-fine-dosing.151/

 

I'm going to tag @Wendy&Neko who is our go-to person for Acro/IAA.

 

Wendy is our expert on acromegaly. She's on the west coast she typically doesn't log in until later in the day.

 

I use SureComfort U100 1/2cc (.5mL) syringes from ADW. They are whole unit markings up to 50 units. I switched when he was getting above 30 units so I wasn’t having to use 2 syringes. Howie is currently on 35 units. Cabergoline has mixed reactions on some cats. I never saw the drastic reductions that some kitties have had (not all who use it are also IAA like ours). He gets .6mL each day but he is at half the concentration of yours. I never started it at EOD. But I do believe the Cabergoline has helped him from staying at really high doses (was up to 55 units before cabergoline). With IAA in the mix as well, it is a frustrating combination. As Wendy indicated earlier, we chase the dose until you get a breakthrough with the tumor that pulses or the anti auto bodies, and then he goes racing back down the scale. I just offer this to temper some expectations that you may/not see immediate reactions. He needs the dose he needs regardless if it makes sense or not. Wendy will need to respond about dosing with the switch to Lev. Big hugs…I know you’re frustrated and scared. Many of us have been there and still continue to live in that space.

 

Hello over on this forum. We usually counsel Acromegaly kitties that are starting Levemir to begin with 70% of their current insulin dose. This is because some cats will have a strong reaction to Levemir. Many do not (my Darcy did not) but it is good to be cautious. You should know within a couple of days whether Mister is one of the cats who does. Then you can take him back up pretty quickly in dose if he doesn’t have a strong reaction.

This is what I did with Wendy’s advice. Started with a 70 percent dose.

 

Typically when switching from an insulin like Prozinc to a long acting insulin like Levemir, we would take the previous dose of Prozinc and how the kitty was doing on that dose into consideration in deciding a starting dose for Lev.

In my experience, it is only when switching between two long acting insulins like between Lantus and Levemir that you would start off with 70% of current dose.

Given the last couple of days worth of numbers in your SS, I'd probably stick with 11u and see how that works. You'll want to get a feel for the new insulin and how it influences Mister's BG, by getting some additional extra tests to determine onsets and nadirs. The cycles can be quite different than what you experienced with Prozinc especially when the depot starts to build. Kind of feels like being a newbie all over again, until you can get more data on how Mister deals with Lev. You may find that onsets are a little later, as are potentially the nadirs. I have had some nadirs on Lev that actually were at preshot, or sometimes at +14-15, which means you may at some point need to get comfy with the idea of shooting a lower number than you perhaps have been used to in the past.

I'm not sure how the Cabergoline may affect things in the near term.

Be sure to insert a new blank line in your SS and add comment Switched from Prozinc to Levemir, so it is clear when you've started the new insulin. Best of luck.

 

If you were going to see anything drastic from cabergoline I suspect you would have seen it by now. Like Suzanne said, we usually recommend starting at 70% of current dose due to possibility of strong initial reaction, but his numbers are high and flat so see what Wendy says. You would give that dose about 5 days for the depot to build, and then after that can increase per TR method (you are following MPM on ProZinc which is almost identical to TR, there are some slight differences on when to increase and decrease).

Since he is on Cabergoline we do usually recommend a reduction point of 70 for TR (rather than the 50 the sticky says). It gives you a little extra padding in case the cabergoline starts to kick in on you

 

I think it’s fine to go ahead and start the Levemir now since it’s been a few weeks since you started the Cabergoline. It does take a few weeks for Cabergoline to kick in, bit with the cautious starting dose that I was talking about in the above post, Mister can be safely and carefully transitioned to Levemir. As I said, Darcy did not have a strong reaction and I needed to increase his doses back up closer to where we had been on Lantus- about 15% increases at a time. Then his Cabergoline also started to help out and we were able to start reducing insulin. He never did get back up as high as his highest Lantus dose.

 

Check out my spreadsheet. We started Cabergoline on 3/6 and started Levemir on 3/27.

 

He was up to 41 units of Lantus. My starting dose of Levemir was 29 units, which was 70 percent of 29 (slightly rounded up). I held that dose for three cycles when it was apparent that he was not having a strong reaction. I was advised to increase by 15 percent so we went up to 33 units where he was for a little while and then the Cabergoline started to do its thing and I did my first ever reductions! Hope this helps.

 

Welcome over on this side of things. Glad to hear the Levemir finally arrived. Like Christie correctly stated, we do NOT reduce the dose when switching between Prozinc and Lantus or Levemir. We only reduce the dose when switching between two depot insulins. Take a read of our Dosing Methods Sticky Notes which has a section on starting dose. So 11 units would be good to start. If you can post here the day you start and maybe for a few days after that, we can determine if you can be fast tracked up in dose. There are allowances for that as well, should Mister be stuck in high numbers. But post first so an experienced person can advice you on whether an earlier increase would be appropriate.

Since you are only doing the cabergoline every other day, it's going to take a while to build up enough to impact his numbers. I wouldn't worry about it at the moment.

As for syringes, most people use the 30 unit ones with half unit markings until they get closer to 30 units, should you get near there. Some acros are sensitive to small changes (Neko was), some aren't. We don't know yet where Mister fits in. Typically over 10 units your changes are by at least 1 unit (think around 10% of dose), but if tweaking a dose that's mostly good you might end up with 1/2 unit changes.

 

Hi! I really hope Mister does well with the Levimir!

 

Well, I want you to know that I am wishing you and Mister the very very best. I do hope the Levemir will be beneficial and that the Cabergoline will help him. I will be keeping an eye out to see if y’all are okay.

 

How’s Mister doing? It would be a good idea to put a row on your spreadsheet to indicate when you started the Levemir. I hope he’s feeling well.

 

Thanks for the well wishes. About to transition this weekend to Levemir, syringes just got here. Mister is up to 12u of ProZinc. Absolutely shocked his numbers aren't going lower. At this dose levels he absolutely FLEW through the entire bottle of ProZinc, I feel like I just bought it a couple weeks ago.

Probably will switch to Levemir tomorrow morning.

 

We will be thinking of you.

 

I had a very smooth transition from ProZinc so I hope you do too! It takes a bit to get your head wrapped around how the depot works and a much later nadir. Good luck!

 

Good Luck Amethyst has done very well on the Levemir!!

 

How often should I ramp up? I am thinking of doing 2u increases at this point. Still no where close to greens. This is really taking its toll: https://www.felinediabetes.com/FDMB/threads/mister-has-blood-in-urine-again.264436/

 

Good to see some blues again finally! Think of the increases as a percentage of the overall dose. Something in line with 10-15%. Between 10 and 20 units that usually means 1 unit increase and going to 2 units at 20. Let's see what 17 does when he's had 6 cycles before thinking of increasing a larger amount. The nature of the depot means it can take that time to really see what a dose can do. Note for any lurkers, this is a suggestion for higher dose cats with secondary endocrine conditions, specifically acromegaly.

If idiopathic cystitis, likely not caused by sugar in the urine, but could be stress related. Anything else happened to him lately?

 

Nothing stressful AFAIK. He aggressively whines like a baby in the late afternoon right before my workday ends to go outside as I am working from home.

He loves to stalk chipmunks, birds, and squirrels.

 

He's up to 20u now, just switched from EOD Cabergoline to every day dosing today. I'll give it 6 cycles, which means morning of 6/18 I am doing a 2u increase to 22u.

At what point should I just open the wallet and do SRT? Like when is this going to stop?! I just FLEW through using my second Levemir pen in what seemed like a few days.

 

Unfortunately no knowing. A lot seem to top out between 20-30U, but then others hit 50, 60, 80....

If SRT is something you're willing/able to do no harm in calling around to get some quotes, consultations, etc. I don't know how far out those kinds of things are booking

 

You might want to read this post - specifically the second one on there. Julie costed out her current costs on insulin vs after SRT. Of course that is over 10 years ago and the prices have gone up, but it'll give an idea of what to look at to do the comparisons. When I booked SRT, it was three weeks after I inquired. But that was also a while ago. Thankfully there are a lot more location options now too.

 

If I get to 30u we're are doing SRT. I will be contacting the UMN vet soon. 30u of Levemir costs like $2800 a year not including supplies.

I keep seeing average lifespan numbers after these treatments. Nearly all cats that do these procedures are older, and the average lifespan of a cat regardless of any illnesses is 10-15 years (and 2-5 years for outdoor cats). So these average lifespan numbers post treatment are simply just restating that general statistic I mentioned previous, no way to know if they lived longer than they would of because of the treatment or died early because of the treatment.

50 to 80u?! At that point, you can't afford NOT to do SRT.

 

Treating acromegaly with something like SRT is about than just cost savings on insulin. Stopping or slowing the effects of the excess growth hormone can make a huge quality of life difference. Lots of stories of side effects going away or reduced after treatment with SRT or cabergoline. Surgery, if successful is more curative, but also more risky.

I find the 10-15 year average to be low compared to what my experience is. But maybe if you include other conditions or diseases. I got almost 5 more years with Neko, which is definitely above the average for untreated cats. The majority of that time she was is pretty good shape.

If you are considering treatment, better sooner than later. The sooner it's done, the less damage done by the excess growth hormone. Also, SRT can take time to work.

 

I am ruling out surgery because I cannot risk an 8-15% chance of death after surgery. That's a huge chance. Plus no one locally does the surgery. Unless someone can convince me otherwise. In the end, I want the best possible Quality of Life and treatment for my cat. That's all that matters.

I just sent an email to the UMN to do a free phone consult and will move forward with SRT now. @Wendy&Neko @FrostD, and anyone else, let me know if this is not the optimal decision.

 

Here's the costs associated with Levemir (and I added ProZinc) according to my calculations. Let me know if these look correct: https://docs.google.com/spreadsheet...nml_vpmnBnwHpet7JIea7C4zsYhsEa2j6j7Z5/pubhtml

 

One thing for the spreadsheet, one usually draws a bit more than the dose they need, maybe 1/4-1/2 unit? To get rid of bubbles and fine tune the exact dose.

Will be interesting to hear the cost from UMN. If local, you'll be lucky that travel/hotel costs aren't part of it.

Some people with higher dose cats add Regular or R (Humulin) insulin. It's a shorter acting insulin that can take the numbers down. Levemir works great at keeping lower numbers flat, not so good at yanking down higher numbers. Just mentioning it as an option. I've seen a couple people who didn't want to give really high doses of Levemir, so compensated by giving R too. But then you've got more syringes, it requires more monitoring. A tradeoff. Plus you need to find someone to work with you to learn how to use it who has experience using it.

 

The optimal solution is whatever works for you and your desires for you + Mister.

We definitely started with a cost analysis as well for everything (cabergoline, may need multiple syringes per dose beyond a certain amount, etc).

The big unknown in terms of cost is if/when/how the SRT will affect dose. On one hand I think of Eddie who started around 15U, got down to about 7U-ish, but is back around 11U-ish now. Wendy definitely knows the trends better than I do.

Mister is still a pretty young cat, so it's not like he's 15 and you're trying to weigh everything.

 

SRT seems to always affect the dose, the question is to what extent and how long until it starts. Neko started down dose on the drive back home from CSU. I've seen another go up for 3 months to 50 units before turning it around after SRT. That cat had quite a bit larger tumour than Neko did. I've seen another at on 80 units come down considerably in dose. That caregiver stopped posting after a while so not sure how it ended up. Eddie's an oddball, he had failed hypophysectomy first, so part of his pituitary already gone, before SRT. His brother, exactly the same combo of treatments, went OTJ after SRT. ECID, each acrokitty even more different.

SRT neuters the tumour cells. They have to live their life and die. It just depends where in their life cycle they get zapped.

 

UMN VMC vet called two hours before my appointment for the initial visit for SRT consult and said they don't trust the accuracy of their machine for this particular procedure.

Back to the drawing board. Are there any known good vets that do SRT near MN?

 

I am so sorry about this. I know how frustrated you must be. I see you had some more nice blues last night, and I'm hoping more today.

 

I am suddenly in blue numbers now after consistent high numbers for many months.

No idea if this is a fluke due to him not eating well yesterday or what.

The last two days I've given a full dose when he was slightly below 200. Should I be looking to do a decrease?

 

No! These are pretty good numbers. You want to keep seeing them. Depending on the dosing method you are using, you reduce if you see a number either under 50 (human meter) if following TR, or under 90 if following SLGS.

 

Cabergoline! You switched to daily dosing. Or maybe you hit a good dose…. Or both. I’m happy you are seeing better numbers. It’s Very gratifying to see!

 

How is his eating today?

I have a running theory that with an IAA cat, if they get sick, it pulls the immune system a different direction and you can see better numbers for a bit. It happened with Mr Kitty twice and it's the only explanation I could come up with.

That, or it's cabergoline kicking in. Or you're hitting a breakthrough dose. Or perhaps IAA breaking a bit. Endless possibilities lok