Basal And Bolus Insulin: The Confusion Ends Here

Do you know the difference between “basal” and “bolus?” If you don’t, we’re here to help.

If you have diabetes and are taking insulin, you probably either give yourself insulin injections periodically or have a pump that injects insulin for you throughout the course of the day. Either method can be effective, but these two ways of getting insulin into your body have one distinct difference. Injections are considered “boluses,” while pumps have the ability to provide a basic (or “basal”) amount of insulin all day long and also perform boluses when necessary.

So now you may be wondering what the difference is. What are these “basal” and “bolus” terms? Well, the basic answer is that in a normal human body where the pancreas produces insulin and the insulin does its job, basal insulin is the low dosage of insulin that the body is constantly producing and shipping out to the cells that need it. It is the basic amount of insulin needed to function.

Bolus insulin, on the other hand, is what the body produces when a person eats carbohydrates or participates in some other activity that increases the need for insulin. It is an extra shot of insulin when you need it.


People with type 1 diabetes don’t produce any insulin at all and require pumps or injections to keep their blood sugar levels within a healthy range. Many people with type 2 diabetes still produce insulin, but their bodies have trouble getting it where it needs to go. Pumps are able to provide that basic amount of insulin needed throughout the day as well as boluses when necessary, while injections only provide boluses.

Does that mean you need a pump in order to function like a “normal” human being? Well, yes and no.

The short answer is that having a pump is much closer to the way insulin works in the average human body. So yes, if you want to have basal insulin acting in your body all day long, you’ll probably need a pump. But in some scenarios, basal insulin doses are not really necessary.

A pump isn’t for everybody. If you’re in good control of your diet, exercise routine, blood glucose testing, and insulin injections, you may not need a pump. Particularly for people with type 2 diabetes whose own insulin may still be doing some of the job on its own (but even for those with well-controlled type 1), basal insulin may not be necessary. But even for those with type 1 diabetes, longer-lasting insulins and having set routines for injections and your diet could eliminate the need for basal insulin.

Insulin injection pen.

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Of course, whether you choose injections or a pump, you’re still going to have to count carbohydrates. A pump can be set up to provide a certain amount of basal insulin, but it will only give boluses when you tell it to. No matter which option you choose, you’re still in control of your blood sugar and responsible for managing your treatment plan.

If you have questions or concerns about basal and bolus doses or whether you’re better off with a pump or manual injections of insulin, talk to your doctor.

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