What to do with low preshot test numbers

Q: My cat's pre-shot level was way below the usual value. Should I give the injection?

A:
There's no hard and fast rule, but if you don't have data on how your cat responds to insulin, here are some general guidelines. Below 150 mg/dl (8.3 mmol/L), don't give insulin. Between 150 and 200 (8.3-11.1 mmol/L), you have three options: a.) give nothing; b.) give a token dose (10-25% of the usual dose); c.) feed as usual, test in a couple of hours, and make a decision based on that value. Above 200 (11.1 mmol/L) but below the cat's normal pre-shot value, a reduced dose might be wise. In all cases, if you are reducing or eliminating insulin, it's wise to check for ketones in the urine. Above the normal pre-shot value, give the usual dose, but if the pre-shot value is consistently elevated, it's a good idea to schedule a full glucose curve to see whether a change in dose or insulin is appropriate. In most cases, the target "peak" value should not be below 100 mg/dl (5.6 mmol/L), and for some cats it might be higher.

Keep in mind that these are general guidelines, and they should be personalized to your own cat's reactions to insulin. If your experience is that your cat does not became hypoglycemic with a dose which is close to her usual, then your experience should be your guide.