Brand new to forum as of last night. 16-yo domestic short hair that has been on twice daily Lantus for 6 years and Fancy Feast classic chicken pate. Fine until last weeks. Think I missed some signs... Desperate for advice on whether to dose or wait 6 more days until an appointment with an internal medicine specialist (current course recommended by vet)? Kitty (Dinah) was fine for 5.5 years, but has had an odyssey over the past couple of months. Current vet recommendation is to withhold insulin. Comprehensive details below. Thanks to anyone who reads through it and can give advice on - to dose or not to dose? ====================== Imagine that your 10-yo cat was diagnosed as diabetic 6 years ago (rapid weight loss and intense thirst). And imagine that, for the past 6 years, you didn't know about this forum, or the concept of TR control, or the forum's spreadsheet, or not to use (very small amounts) of dry food as a treat for getting injections or ear pricks. But you have been doing just fine regulating your cat (healthy, fine clinically, seemingly playful and happy, etc) on twice daily injections of Lantus and Fancy Feast chicken pate until just these past few months, with the last 4-6 weeks being particularly challenging to figure out. Over these quite successful years, she has gradually required less insulin and less insulin. Never more. Year 1 and Year 2 at 1.0 to 0.75 units per dose. Years 3-4 at 0.75 to 0.6. Year 5 going 0.6 to 0.4. In the last 6 months, she's been showing the need for 0.4 to 0.25 to 0.1 and showing signs that 0.1 may be too much relative to her historic norms. On top of all this, 0.1 units is extremely difficult to dose accurately, as the residual liquid in the syringe needle itself is rather significant relative to the actual dose volume. So one extra little bit of pressure or one wiggle by kitty and significant-relative-to-her-very-low-dose insulin is injected. You start noticing lethargy and her pre-shot BGs much lower (or higher) than historic norms. Sometimes very much lower or very much higher. [She is not on TR. That concept is brand new to me upon finding this forum yesterday. Historically, she has been 250-300 pre-shot falling to, and cruising at, between 80 and 120 during +3 to +9. This regimen, while not TR, has worked. For literally 5.75 years.] The recent pre-shot numbers on the 0.1 units dose might show 80 or 60 or 400. I only give if she's above 275 based on what has worked for her historically. Instead of interpreting this wonkiness and progressively lower dosing as a sign that she might be ready to try no insulin, you instead become fixated on how difficult administering small doses is. So, vet approved, you switch to PZI, which is U40, so that you can measure out more liquid, and you use a U100 syringe (with conversion of course) to facilitate larger volume, and presumably more accurate, dosing. Upon this switch to PZI 3.5 weeks ago, your vet somehow (I'm absolutely kicking myself here...) talks you into using 0.5 units PZI instead of the 0.1 units Lantus because she knows that (1) they have different formulations for different durations of action and that (2) the insulin proteins themselves have differences at several different amino acid positions and (3) are produced by different production processes. For the first week on PZI, you ignore the weird BG because 'hey, her body is getting used to something new.' You catch her pre-shot extraordinarily low (for her) a few times (80 at +12, remember she's normally 250-300 and been doing fine with that for 5.75 years). The next day, you find it at 450, which is higher than you've ever measured her in 6 years! Enter the FreeStyle Libre sensor, where you are getting BG numbers in real-time, literally every minute if you want but a minimum of every 15 minutes in the data log. We periodically check with our AccuChek meter and ear pricks and confirm that the FreeStyle Libre and the AccuChek meter we've used for years are measuring the same. (Hooray for the FreeStyle Libre and for the vet's installation of the sensor. It is incredible to have this level of information like a human diabetic would and not have to do any ear pricks, except an occasional doublecheck.) During the first week with the sensor (week 2 since you switched to PZI), you witness the same dose of insulin becoming less effective with each subsequent dose. The curves shift higher in BG at all time points and get tighter. You also occasionally observe long periods of flat, high, jagged BGs. You also note sharp falls and sharp rebounds ('bounces' maybe you call them...). You go higher on the insulin and administer with overlap in a cycle to force her back down. It works and drops her into her historic range but the fall and bounce are both crazy fast (100 BG down or up in an hour). You come across websites describing the Somogyi effect that seem to perfectly describe all of the various patterns that you are witnessing. So it dawns on you to cut the insulin dose (from 0.5 to 0.4 to 0.3 to 0.25 to 0.2). Even as you walk down to low doses, you see rapid falls and rises like a roller coaster. She starts peeing sweet-smelling, sticky urine in your entryway (not in the litter box in the basement). You say to heck with PZI as a failed experiment, it's back to Lantus. It worked for the last 5.75 years just fine. She continues to spray sweet-smelling pee in the entryway (and not in her basement box during these days), though she does use her box for poop. You give the same Lantus dose (0.1 units) that you were doing up until a few weeks prior when you attempted the switch to the PZI. That drops her BG from 500 down to 350 in about +3.5 hours. But it just sits there at 350 for the entire 12 hours. It's flat. Not U-shaped like historic curves. You dose a second time with Lantus at 0.1 units. Again, a drop (from 350 to about 225) and 12 hours of basically flat BGs. You go for the 3rd dose of 0.1 units Lantus at +12. You witness her BG rapidly dropping from 270 down to 50 and see it not leveling off. You observe it hit "LO" (below 40) and spike straight up to 288 only 80 minutes later. She vomits twice during this period and drinks excessively. No seizures. You call ER in middle of night, and decide with person on other end that with no seizing and isolated vomiting to keep her at home and avoid the stress of car and hospital. You are terrified to administer insulin after this. Her BG goes "HI" (ie above 500) for 6 hours, and you haven't given insulin in 24 hours. So you opt to dose your most minuscule dose ever - 0.05 units (below zero marking but can still make out a tiny bit of liquid). She drops from "HI" to about 390 within 3-4 hours. But she again does the thing where the BG is very flat for the next 20 hours. This time you waited longer than 12 hours of flatness to see if the flatness went away. It didn't, so at +21, you go ahead and very nervously dose 0.05 units. Eureka - she gives her first normal looking U-shaped curve with a gradual descent to a +7 nadir and a gradual climb back to pre-shot at +14. But her nadir is still high at 190 (reminder: hers are historically 80 to 120 for 5.75 years). So she's spent the beginning and end of the cycle in the 300s and low 400s. You dose 0.05 units again. But then your sensor's 14 days have expired. And both you and your spouse's Holidays are over, and you are back to work all day and can't get any BG readings. So all you have is a +10 of 440 (higher than the AMPS). Also of note after all this hyperglycemia and insulin overdosing on the PZI... in addition to sweet-smelling pee sprayed in atypical locations, she has started to shake her front legs out in front of her (neuropathy no doubt). She is thirsty. She is eating about 40-50% more food. And you find her sitting on her haunches staring glassy eyed at times (this is atypical). Her pupils do respond to light. Vet and emergency hospitals don't think ER visit warranted since not seizing or vomiting. You discuss all of this data and clinical observations with the vet (who is finally now back from the Holidays) yesterday (Jan 6th) on the same day the sensor stopped. She recommends an appointment with an internal medicine expert, which you make. But the soonest appointment is still 1 week away. She also recommends to stop giving insulin for the time being. You agree, thinking that you misread all of the signs during these past few turbulent months where her insulin dose was coming down and down and pre-shot numbers were wonky. So she has now not had insulin for over 36 hours. All five BGs we've taken during these 36 hours have been 400-440, so seemingly flat but high. FWIW, I have observed no leg shaking (which was prevalent for a couple of days). And she had a kitten-like play session this morning with the laser. However, her appetite is still up. Her thirst is still up. Her peeing sweet-pee in the entryway is still happening. So, the question is... Do I wait 6 more days with no insulin until I finally get seen by an internal medicine specialist? (Having dosed insulin every day for 6 years, this is incredibly unnerving.). And if I do dose in the interim, how the heck do I accurately measure 0.05 units? (Anyone ever used a 0.2 to 2.5 microliter micropipettor to aid with this?) If I missed all the signs of potentially wanting to go off insulin and instead created a huge horrible overdose storm these past few weeks, will her body gradually rid itself of this sugar? I did buy keto strips this evening and will test for ketones the next time she pees in our entryway. I know that was a lot of information. Major thanks to anyone who made it this far. Desperate for any advice. I did mine the data from her FreeStyle Libre sensor and put it into the forum's spreadsheet in my signature block. I have the full data (14 days worth every 15 minutes) plotted in Excel if anyone wants to see it visually instead of in the tabular format.