What Is a Glucose Curve for Cats, and Why Does Your Vet Want One?

If your cat has been diagnosed with diabetes, your veterinarian has probably asked for a glucose curve. It’s one of the most useful tools in managing feline diabetes, and one of the most misunderstood.

What a glucose curve actually is

A glucose curve is a series of blood glucose measurements taken at regular intervals (commonly every 2 hours over 10–12 hours), usually starting just before an insulin injection.

Plotted on a chart, those points draw a curve that answers three questions a single reading never can:

1. Is the insulin working at all? Does glucose come down after the injection?
2. How low does it go? The lowest point, called the nadir, typically occurs somewhere in the middle of the dosing interval. Where the nadir lands, and how low it dips, is the most important safety information in the whole curve.
3. How long does the effect last? Does glucose stay in a reasonable range for most of the cycle, or rebound quickly?

Your veterinarian uses the shape of the curve, not any single number, to evaluate whether the current dose and schedule suit your cat. Dose decisions are theirs to make; the curve is the evidence they make them with.

Why home curves beat clinic curves

A curve done at the clinic has a built-in flaw: stress. Many cats run dramatically higher glucose in a clinic cage than on their own sofa (stress hyperglycemia), which can make a working dose look like a failing one.

A curve collected at home, with your cat relaxed and eating normally, reflects reality. That’s why many vets now coach owners through home curves: same technique as everyday home glucose monitoring, just repeated through the day.

Practical tips for a home curve day

• Pick a quiet day when someone is home anyway. A weekend works well.
• Feed and inject exactly as your vet prescribed; the point is to observe a normal day.
• Log each reading with the exact time. Note meals and anything unusual (vomiting, big play session, a stressful event).
• Don’t panic-interpret mid-day. One odd value happens; the shape is what matters.
• Send the whole set to your vet, including the context notes.

The data problem nobody warns you about

Here’s the unglamorous truth of caring for a cat with diabetes: the testing is the easy part. The hard part is the bookkeeping. Readings on sticky notes, in three different phone apps, in a notebook the other family member can’t find. When the vet asks “how’s he been trending since March?”, memory fills the gaps, badly.

Good decisions need good records. That’s the core of what we’re building at Pawpoy: every reading logged in seconds, curves drawn automatically with your cat’s target range shaded in, and a one-click vet visit report, a clean PDF of curves, time-in-range, weight trend, and current foods that your vet can absorb in 30 seconds.

Pawpoy is free in early access and we’re onboarding gradually. Join the waitlist and we’ll email you when your spot opens.

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Pawpoy is a decision-support and tracking tool, not veterinary advice. Glucose curves should be planned with and interpreted by your veterinarian. Never adjust insulin doses on your own.