Blood Glucose Curve and Insulin Dose Calculator
Plot a serial blood glucose curve, calculate nadir, duration of insulin effect and time in range, and get a structured interpretation built on the 2018 AAHA Diabetes Management Guidelines for Dogs and Cats. For use by veterinary professionals.
1 Patient
2 Insulin and timing
3 Curve data
Samples
| Time | Blood glucose (mmol/L) | Hours post-insulin |
|---|
4 Glucose curve
5 Curve metrics
6 Interpretation and dose guidance
AAHA 2018 targets and reference values used by this calculator
| Parameter | Dog | Cat |
|---|---|---|
| Acceptable blood glucose range through the day | 100 to 250 mg/dL (5.5 to 13.9 mmol/L) | 120 to 300 mg/dL (6.7 to 16.7 mmol/L) |
| Ideal nadir | 90 to 150 mg/dL (5.0 to 8.3 mmol/L) | 90 to 160 mg/dL (5.0 to 8.9 mmol/L) |
| Hypoglycaemia threshold used here | Below 65 mg/dL (3.6 mmol/L) | Below 65 mg/dL (3.6 mmol/L) |
| Approximate renal threshold | 180 to 220 mg/dL (10 to 12 mmol/L) | 240 to 290 mg/dL (13 to 16 mmol/L) |
| Ideal duration of insulin effect on q12h dosing | 10 to 14 hours | 10 to 14 hours |
| Curve sampling | Every 2 hours for at least 12 hours, starting immediately before the insulin dose. Sample every hour if the glucose is falling fast or hypoglycaemia is suspected. | |
Duration of insulin effect is measured here from the injection to the first point after the nadir where glucose rises back above 250 mg/dL (13.9 mmol/L) in dogs or 300 mg/dL (16.7 mmol/L) in cats, using linear interpolation between samples.
Insulin reference table
| Product | Type and strength | Typical starting dose | Usual duration |
|---|
Concentration is the single most common cause of an insulin overdose. U-40 products must be drawn with U-40 syringes and U-100 products with U-100 syringes. Drawing a U-40 insulin with a U-100 syringe delivers 40 percent of the intended dose. Drawing a U-100 insulin with a U-40 syringe delivers 250 percent of the intended dose.
SGLT2 inhibitors such as bexagliflozin and velagliflozin are not insulin. Cats managed on those drugs are not monitored with insulin glucose curves and require ketone monitoring instead. Do not use this tool to make dose decisions for them.
Why a single curve can mislead you
- Day to day variation in the same patient is large, especially in cats. AAHA advises interpreting curves alongside clinical signs, body weight, water intake, urination and fructosamine rather than in isolation.
- Stress hyperglycaemia in hospitalised cats can produce a flat, high, uninterpretable curve. Home sampling or continuous interstitial glucose monitoring is preferred where possible.
- Do not change the dose on a curve that conflicts with the clinical picture. A well controlled patient at home with an ugly in-clinic curve usually has a sampling problem, not a dosing problem.
- Somogyi or insulin-induced hyperglycaemia is over-diagnosed. Confirm a documented low nadir before attributing rebound to it, and never increase the dose on that pattern.
- Give at least 5 to 7 days on a new dose, and preferably longer for glargine and detemir, before repeating a curve, unless hypoglycaemia is suspected.
This calculator is a clinical decision support tool for registered veterinary professionals. It does not replace clinical judgement, patient history or examination. All dose suggestions are guidance only and must be confirmed against the product label, current formulary and the individual patient before use. Owners should never adjust insulin without veterinary direction.