Hi there, and welcome to you and your kitty.
As other members have already posted, we know only too well how overwhelming and scary things can be in the early days after diagnosis.

Melanie (
@Brashworks), one of our members here, made an absolutely wonderful video about how well her kitty, Genghis, has done since she was diagnosed and successfully treated with insulin. I've posted a link to the video below because I think it will help you to feel more hopeful and positive that your kitty will feel better again.
Lantus is what is known as a depot insulin. Over several days it builds up a little 'tank' (depot) of insulin in a kitty's body; a bit like a chemical pancreas (but one without an OFF switch). It can therefore take administration of several doses before the full effect of a dose can be judged.
Home testing will help you to keep your kitty safe and monitor how he is doing on a particular dose.
Tracking blood glucose results in a spreadsheet will help you to better understand how your kitty is responding to his insulin and it will help you to fine tune your kitty's dose so that he can safely get the greatest benefit from his insulin treatment. The spreadsheet also helps members here to give you better tips and suggestions as you go along.
As his body starts to use the insulin you should first start to see improvements along the lines of less drinking and less peeing. If he's currently hungry all the time then his appetite should start to return to normal as the insulin treatment starts to benefit him. Over time he should start showing more interest in grooming. Between that and the insulin helping his body to use nutrients properly again his coat condition should start showing clear signs of improvement. If he has lost too much weight prior to Dx then the insulin treatment should halt the weight loss and he should start regaining lost weight as treatment progresses. The transformation that effective FD treatment brings about can be
jaw-droppingly impressive.
Can you let us know your kitty's current weight, and whether he is underweight, overweight, or at ideal weight. Also, does he have any other medical issues alongside the diabetes Dx?
Mogs
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