How to calculate an insulin dose


Before using the dose calculator, make sure your therapy settings are correct and that all of your recent doses are logged.

  1. Open the InPen app.

  2. Tap the orange dose calculator icon on the home screen.

  3. Enter your current blood glucose and/or the number of grams of carbs you are eating or plan to eat. If you have already connected your glucose meter to the InPen app, your current blood glucose will automatically appear in the blood glucose cell.

    Dose calculator screen on InPen app

    View the Recommendation or Warning at the top of the screen and act accordingly.

    • If you see Units of Insulin, this is the recommended number of units of insulin to take now.

    • If you see Grams of Carbs, eat that many grams of carbohydrates now to avoid low blood glucose in the near future.

    • If you see 0 Units, no additional food or insulin is recommended at this time.

    • The Eat fast acting carbohydrates to treat your low blood glucose recommendation will be shown if you entered a very low blood glucose value, regardless of active insulin or carbs entered. If your blood glucose is low, it is important that you eat fast-acting carbohydrates. If you believe the message is in error, then check the blood glucose value you entered.

    • The Monitor Glucose Warning will be shown if your glucose may drop low due to your active insulin. Check your glucose frequently over the next few hours.

    • The Insulin Stacking Warning will be shown if the recommended dose plus active insulin is greater than your maximum dose setting. If you've seen this warning, verify that your glucose and carbohydrate values are correct.

      Eat fast acting carbohydrates recommendation screen on InPen app

  4. When you are done using the calculator, tap Save to automatically save your entries to the Logbook.

Additional information about the dose calculator:

Multi-part dose

The InPen can deliver a maximum of 30 units per injection. For doses greater than 30 units, the dose must be split into multiple doses. If for any reason a dose is split into multiple doses, each dose that is delivered will be logged separately. To ensure that your insulin is tracked correctly, always take the larger dose first. If you forget how much insulin was recommended, open the logbook to view the recommendation.

The math behind the dose calculator

If you entered a value in the carbs cell, you can see the math used in the calculation by tapping the arrow in the recommendation banner at the top of the screen. Tap Calculator to return and save your dose. Note that dose recommendations are rounded down to the nearest half unit.

Dose calculator screen InPen app

Blood glucose range

The dose calculator only accepts blood glucose values between 20 – 600 mg/dL. If you believe you receive the following message in error, then check the value you entered. If your blood glucose is outside this range, take immediate action to correct it prior to using the dose calculator.

Blood glucose range screen InPen app

Carbohydrate range

The dose calculator only accepts carbohydrate values between 0 - 200 g. If you receive the following message in error, then check the value you entered.

 Carbohydrate range screen InPen app