aw, anna, keep your chin up. i agree with wendy, it's very likely he's got one of the high dose conditions, or perhaps both iaa and acro.
punkin had acro only and he got up to 15.5u before we had him treated. Lauren's Tommy was diagnosed the same time as punkin and his IGF-1 was higher, and she did great keeping him regulated.
the best advice that people here gave me was to keep my eyes on the blood sugar numbers, not the size of the dose. I repeated that to myself a bazillion times. let's just work on getting Bailey into better numbers. When kitties are like yours, i like to refer to the Tilly page description of the protocol. It gives the option of increasing after 2 days, depending on the nadirs:
http://www.tillydiabetes.net/en_6_protocol2.htm
Most cats need to have their dose increased. Do it in 0.25 IU or 0.5 IU steps (0.25 IU if the cat is getting a low dose and/or relatively low BGs, 0.5 IU if the cat is getting a higher dose and/or relatively high BGs). Hold each dose for 5-7 days. However, if the cat is producing continuously high BGs (nadir always >=300 mg/dl), only hold the dose for 2-3 days before increasing it by 0.5 IU. Alternatively, if the cat is continuously producing moderately elevated BGs (nadir always >=200 mg/dl), increase the dose every 2-3 days by 0.25 IU ( if the cat is getting a low dose) or 0.5 IU (if the cat is getting a higher dose). From this point onward test for ketones once per week, or more often if the nadirs are still >=200 mg/dl.
You can see from Bailey's ss that he's getting dose increases, giving you a lower nadir (although still mostly high 200's), and then his numbers go up and stay there. Sometimes when you inch up in smaller increases, or you take too long between dose increases - even the 6 cycles recommended in most situations, it encourages the higher numbers and takes even more insulin to get the numbers down. For that reason, in your specific case, i think taking the more aggressive options listed above, using the 0.5u increases and perhaps increasing after 4 cycles on a dose until you see blues is a smart way to go. This isn't for other kitties, but specifically for Bailey because of his particular situation. I don't want lurkers to think this is the best way for most cats. For most cats we are more conservative, but cats with high dose needs aren't most cats and a more aggressive approach can be more helpful for them.
if you want to change insulins, i would go to Levemir (detemir) not PZI. We know that longer duration helps smooth out a cat's blood sugar and that's all better for them. PZI's duration is shortest of these three insulins, Lantus is in the middle, and Levemir has the longest duration. But you can keep on with the Lantus and if you want to switch, i'd use up the Lantus first. It works fine. If Bailey begins to flinch when you're giving him shots, he may be reacting to the acidic base of the Lantus. It didn't bother punkin but it does bother some cats, and sometimes it begins to bother them as the dose gets larger. Levemir has a neutral base and doesn't sting. Here is a good link on what the differences are between these two.
http://www.diabetesclinic.ca/en/diab/2treat/lantus_vs_levemir.htm
We have several high dose kitties here. You're not alone. We'll continue to help you, so don't despair. You will get to the right dose and Bailey will get under control. :YMHUG:
