Good on you for taking her in!! Diabetes is a completely manageable disease... although it is not necessarily cheap, we have a lot of tips for saving you money in the long run.
First, Prozinc is a good insulin! Although it is not necessarily cheap. None of the insulins we recommend are really cheap. Insulin is one thing you don't want to cheap out on! Prozinc should last you quite a while if it's handled properly (some report upwards of a year). Just keep an eye on it for discoloration or loss of effectiveness.
The best food for a diabetic is low carbohydrate canned or raw. No dry food at all, even grain free. Low carb canned is very cheap and not any more expensive than feeding dry - some common household brands are Friskies, Fancy Feast, Special Kitty, and of course there's more premium brands like Wellness, Merricks, Evo, etc. It all depends on your budget. Take a look at
this chart compiled by feline vet Lisa Pierson - it lists all of the carbohydrate percentages for a lot of common foods. You are looking at the "C" column under the "CALORIE%" title. You are looking for something under 8% carbs, but 3-5% works best for most. One missing from this chart is Petsmart's Grreat choice - any of their pate style foods (NO gravy) are low carb and very cheap. My cats like poultry platter.
And yes, you can use a human meter on her! The most expensive part of diabetes is home testing - testing strips for meters can get VERY pricy since we recommend testing at least 3 times a day! But fortunately there are cheap meters out there. If you're in the USA, the ReliOn Confirm and Micro from Walmart have very reasonably priced strips ($36 for 100) and there is also the new ReliOn Prime that has the cheapest strips ($9 for 50!!!) you also have a few other options, such as ordering strips online from places like American Diabetes Wholesale, local classified sites, or reseller sites like eBay.
I think a vial of insulin lasts 28 days and must be kept in the fridge and never shaken. Only rolled gently to mix the contents. Some people i think use their vials for longer - that's just what my vial says.
The 28 day expiry is for Lantus and it is applied to insulin kept at room temperature. This is a direction for human diabetics, because human diabetics use a LOT larger doses than our cats do, and will use a whole vial of Lantus before it expires, whereas our cats would barely make a dent in it! We refridgerate Lantus to make it last longer and use pen cartridges as they are more economical - I use my pen cartridges down to the last drop (3-4 months each one) but you could potentially get 4-6 + months out of a vial... you would still have to throw away some of it unless you have a high dose kitty.
