The insulin activity curve
Below the glucose and insulin charts, the Charts tab draws Expected Insulin Activity (estimate): a blue curve of relative insulin activity over the last 12, 24 or 48 hours, with a dashed green line at each injection and an orange dot at the estimated peak. It is a textbook estimate — the published typical onset, peak and duration for the insulin type each dose was recorded under, shaped into a curve and added up — not a measurement or prediction of your cat’s response. The app says so under the ⓘ button, on the disclaimer you agreed to, and here: do not use it for dosing decisions.
How to read it
Section titled “How to read it”| Element | Meaning |
|---|---|
| Blue area and line | Relative activity, sampled every 15 minutes, drawn with a smooth curve |
| Vertical axis: Low / Mid / Peak | The curve is scaled so its highest point in the visible window is “Peak”. The axis is deliberately not a percentage of anything measurable — labelling it 0–100 % invited reading it as a measurement of the cat |
| Green dashed lines with 2.0u and a syringe | Injections inside the window, labelled with their units |
| Orange dot, Peak ~7:42 AM | Where the combined curve is highest |
| Current: Lantus (Glargine) (under the title) | The insulin type currently selected in Settings |
| This window includes Vetsulin/Caninsulin and ProZinc (PZI) doses. | Shown only when the doses in the window were recorded under more than one type — the curve reflects each dose’s own type, not the Current one |
Under the chart, two From the typical curve cards:
- Expected peak — the clock time of the orange dot (N/A if the curve is flat).
- Doses still in window — how many logged doses have not yet run past their type’s duration as of now (a Lantus dose counts for 24 hours, an NPH dose for 7).
The segment control offers 12h, 24h and 48h, each ending now. Doses given before the window still contribute the tail of their curve inside it — the app looks back a full 24 hours (the longest duration of any type) before the window start.
What the curve is built from
Section titled “What the curve is built from”Each dose contributes its type’s shape, multiplied by its units; the contributions are summed and the total is divided by its own maximum, so the result is always 0–1 and only relative height means anything.
| Insulin type (as listed in Settings) | Onset | Peak | Duration | Shape family |
|---|---|---|---|---|
| Lantus (Glargine) | 1.5 h | 5.0 h | 24 h | Long-acting: ramps to a flat plateau at a quarter height for the whole duration, tapering over the last two hours — no distinct peak |
| Levemir (Detemir) | 1.5 h | 5.0 h | 24 h | Long-acting, same flat profile |
| ProZinc (PZI) | 0.75 h | 6.0 h | 16 h | Intermediate: smooth (quadratic) rise to a clear peak, then exponential decline |
| Vetsulin/Caninsulin | 0.5 h | 3.5 h | 10 h | Short-acting: quick (sine) rise to a sharp peak, then a faster decline |
| NPH | 1.0 h | 4.0 h | 7 h | Short-acting, same shape |
| Custom | 1.0 h | 4.0 h | 12 h | Intermediate shape with default numbers |
These are the same three numbers shown under the type in Settings › Insulin Settings and in the Insulin Profile ⓘ sheet (which also carries the disclaimer This chart is an informational estimate based on published typical insulin curves…).
Which type a dose uses. Every dose is stored with the type name it was logged under, and the curve models it with that type. If you change insulins in Settings, old doses keep their old shape and new doses get the new one — that is what the mixed-types caption is for. A dose whose recorded name is not one of the five known insulins (a custom insulin, or a hand-edited CSV row) uses the Custom profile; a dose with no recorded type at all (rows from very early versions) uses whatever is selected now.
Empty and error states
Section titled “Empty and error states”- No Insulin Data — Add insulin doses to see activity curve: nothing logged in the last window-plus-24-hours.
- Couldn’t Load Insulin Doses — Your data is still saved. Pull the Charts tab away and back, or reopen SugarPaws, to try again.: the read failed; this is deliberately distinct from “you have none”.