It’s lunchtime. You’re about to eat a sandwich that has 16 grams of carbs per 100 grams. But you had a snack an hour ago. And you played hockey yesterday evening. And you had a hypo last night. How much insulin do you inject?
This is the reason bolus calculators exist. You can keep all of these details in one place on your smartphone, and the calculator…well…calculates.
So, you want to find out how it works. You’ve come to the right place.
Why use a Bolus Calculator?
Aside from the benefit of having that mental maths done for you, a bolus calculator will usually keep a record of what you’ve been up to. This is ideal for showing to your doctor; those details can help establish a pattern. From that, you can see what needs to be improved, and what you’re doing right.
Hopefully, more will be going right once you’ve started using the bolus calculator: you will be receiving more accurate recommendations for insulin dosage, and therefore, greater control of your diabetes as a whole.
In the case of Hedia, establishing a pattern will be even easier since you can transfer your blood glucose measurements wirelessly to the Hedia logbook. This logbook can also contain carbs found on Hedia’s food database.
So, instead of guessing how many carbs are in your meal, you can just search on the app – leading to more accurate calculations.
From a day-to-day perspective, more accurate calculations lead to fewer roller coaster rides. In turn, this helps to lead a fuller life with fewer worries. For more information on why those roller coaster rides might happen – and for tips on how to avoid them – read Blood Sugar After Eating.
Details Needed for Bolus Calculation
You can get any bolus calculator online, but be aware that not all bolus calculators are CE marked. Fortunately, ours is. Say hello to our app, Hedia Diabetes Assistant (HDA).
Once you’ve downloaded the app, and the purple icon is gracing your smartphone, you can get started. To get set up for the first calculation, you’ll need to enter information specific about your diabetes. This is so that Hedia’s recommendations can be tailored to you.
- Pen or pump?
Whether you use a pen to inject insulin manually, or whether you have an insulin pump attached to you that delivers insulin mechanically.
- The units of measurement: mmol/L or mg/dL?
These are the units for measuring blood glucose. The worldwide standard is mmol/L, while the US standard is mg/dL.
- Type of Insulin? (Optional question.)
What kind of fast-acting insulin (for example, Novorapid) and what kind of long-acting insulin (for example, Lantus).
Your ratio that your healthcare professional will help establish. The app will ask you “How many carbs can you eat for one unit of insulin?”. For further clarification, HDA will explain that the insulin-to-carb-ratio is calculated using the 500-rule: “Divide 500 with the total units of insulin (both basal and bolus) you take in one day”.
Insulin sensitivity factor?
Your healthcare professional will help establish how sensitive your body is to insulin. To put your insulin sensitivity factor in HDA’s words: “How much does 1 unit of insulin lower your Blood Glucose?”.
This is calculated using the 100-rule (mmol/L) or the 1800-rule (mg/dL): divide either 100 or 1800 with your daily dose (total amount of insulin taken in a day, including long-acting insulin).
After those questions about diabetes, you will be presented with some questions regarding preferences for the app, such as notification settings. Then, you just confirm the details, and you’re ready to go!
Don’t worry, you won’t be asked these questions each time. The diabetes assistant will save the details for future calculations. Of course, you can also edit your answers in settings.
In case you aren’t familiar with some of the terms bolus calculators use.
Bolus = the dose of insulin taken at a meal
Insulin on board (IOB) / active insulin = the insulin that remains active in the body after a bolus, usually for up to 4 hours
Basal insulin = the dose of insulin that plays a part between meals
Daily dose = the combination of basal and bolus in a day
Correction dose = amount of insulin that is needed to adjust blood glucose when it is above target level
Carbohydrate recommendation = amount of carbs to be consumed when blood glucose is below target level
How to use Hedia Diabetes Assistant
It’s quite easy, really. Just press the (+) icon at the bottom of the screen, and fill in how much detail you want:
1) Current blood glucose level
2) Food and drink
Hedia may also ask you if you have used insulin within the last 4 hours, which you can enter at the same time.
You can choose to add all three or whichever information you want to update. It’s up to you.
It’s important, however, to use your judgment. While a bolus calculator will take a load off your mind, you should still remain vigilant. A calculator can only work with the data it is given: double-check what you’re entering.
Hedia will send a warning if your blood glucose levels are dangerously low. Yet, you cannot always rely on a calculator to tell you this. Use your judgment to see whether a bolus calculator’s recommendations seem right.
What the Bolus Calculator Actually does
It calculates your bolus, yes. But how does it get to giving a recommended dose for the bolus? Hedia Diabetes Assistant uses all or some of the following:
- Insulin-to-carb ratio and insulin sensitivity factor (which you’ve already provided)
- Current blood glucose level (that has been entered when requesting a calculation)
- Carbohydrates entered
- Insulin amount taken within the last 4 hours
These are finally used to calculate:
- Your recommended insulin dose
When you ask Hedia for a recommended insulin dose, you don’t need to enter all of this information. You can even simply enter how much food you’ve eaten, and get a bolus calculation after that.
And Hedia will remember previous entries, so Hedia will have an idea of how much insulin on board (or active insulin) you have. This could be described more simply as: food + correction dose – active insulin – activity.
It’s a clever little assistant, you see.
Download your Bolus Calculator Online
Read more about Hedia’s bolus calculator here, and more about Hedia’s other features on our webpage. You can also check out the guide of our founder, Peter Lucas, on how to use Hedia, and watch our video guides on our welcome page!