What’s a glucose curve?

One thing we found out quickly was the importance of the glucose curve, which is a series of blood sugar (glucose) measurements taken over the course of a day. 

It helped us. It helped our vet. And it helped Parker, though we hated having to poke him so many times throughout the day.

Why run a glucose curve?

The purpose is to track how your dog’s blood sugar changes after receiving insulin and eating a meal. By plotting these values on a graph, you and your vet can see:

• When the insulin starts working (onset)
  
• When it works at its peak (nadir, which is the lowest blood sugar point)
  
• When it starts wearing off (duration)
  
• And whether the dose or timing needs adjusting
  

Think of it as a “day in the life” of your dog’s blood sugar, revealing whether the current treatment plan is keeping them in a healthy range.

Why do we call it a curve?

When you plot your dog’s glucose readings on a graph — with time of day on the horizontal (x) axis and blood sugar level on the vertical (y) axis — the points connect to form a shape that rises and falls like a gentle hill. This is the curve.

A healthy glucose curve should have a predictable shape — not too steep, not too flat. 

A steep drop could signal the insulin dose is too high, while a flat line might mean it’s not working enough. 

The shape of the curve is as important as the actual numbers, because it shows not just how high or low the blood sugar goes, but how it changes over time.

Why is it important?

Every dog’s response to insulin is unique. Even the same dog may have changes over time due to age, weight, activity level, or other health issues. A glucose curve helps:

• Prevent hypoglycemia (dangerously low blood sugar)
  
• Avoid hyperglycemia (persistently high blood sugar)
  
• Reduce diabetes symptoms like thirst, hunger, and fatigue
  
• Guide your vet in making safe, effective adjustments to treatment
  

Regular glucose curves are especially important when:

• Your dog is newly diagnosed
  
• You’re starting a new insulin type or dose
  
• Symptoms return or worsen
  
• Your vet recommends a recheck

What we've learned

Running a glucose curve is a simple yet powerful test that helps fine-tune your dog’s insulin dose so they can feel their best and avoid dangerous highs and lows in blood sugar. It may be a bit unpleasant for you and your dog – especially getting readings in the middle of the night  – but you will be better informed about your diabetic dog’s health.

As a next step, we recommend learning how to run a glucose curve.