Bolus Dose of Insulin

Woman injecting insulin into abdomen.
IAN HOOTON/Science Photo Library/Getty Images

Bolus Dose of Insulin Definition:

A bolus dose of insulin is the dose of regular or rapid-acting insulin that is injected to cover the food you eat in a meal or a snack. When an insulin pump is used, the bolus is given, in addition to the basal rate, to cover food intake. The bolus dose allows your cells to take in the glucose produced in digesting food so you maintain appropriate blood glucose levels.

Bolus doses are also used when blood glucose levels are too high, to lower the amount of glucose in the blood.

The Non-Diabetic Pancreas Delivers Bolus Doses of Insulin

Injecting insulin with each meal may seem unnatural, but you are simply doing by injection what a normal pancreas does in releasing insulin in a person who doesn't have diabetes. Your pancreas should be releasing a small amount of insulin continuously, day and night. This is the basal level of insulin. Then when you eat food, especially carbohydrates, the pancreas detects the increase in blood sugar and releases a bolus of insulin. The insulin then allows the cells to take in sugar, lowering the blood glucose level and allowing the cells to use it for fuel or store it. As a result, blood glucose levels stay within the normal zone and hyperglycemia is prevented.

Taking Bolus Doses of Insulin

Your doctor will work with you to establish how you take insulin and other diabetes medications.

There are many variations in what kind of insulin you take, when you take it, and how much you take. The goal will be to maintain your blood glucose level in the normal zone throughout the day.

When your diabetes results in high blood glucose after eating, your doctor will recommend an appropriate plan for injecting bolus doses of insulin at meals.

 Insulin must be injected because it is a protein and it would be broken down if taken in a pill. It can be injected by syringe, pen, or pump.

Bolus doses are figured by a combination of counting grams of carbohydrates of a meal or snack, and a current blood glucose reading taken before eating the meal. Usually, one unit of regular or rapid-acting insulin per 15 grams of carbs is a good starting point. This may be adjusted according to individual need. A bolus of regular insulin should be injected (or released via the pump) 1/2 hour before the meal. Rapid-acting insulins should be given at the start of the meal.

Bottom Line on Bolus Doses

Work with your doctor to ensure you are on the right medications and you understand when and how to administer them. While having to take a bolus injection when you eat is inconvenient, it is a key part of maintaining blood glucose control and preventing complications from diabetes. You are simply doing what the pancreas normally does and what our bodies expect to have happen when we eat and digest food. Everyone else in the room is giving themselves a bolus dose, even if they don't realize it. You just need a little technological help.


The Basics of Insulin. Retrieved December 13, 2007, from American Diabetes Association.

Insulin Routines, American Diabetes Association, June 29, 2015. Accessed February 11, 2016.