What is basal and bolus?

In diabetes management, "basal" and "bolus" refer to two types of insulin doses that help control blood glucose levels throughout the day.

Basal Insulin

Basal insulin is the background or foundational insulin that your body needs to maintain stable blood glucose levels when you're not eating or digesting food. It provides a continuous, slow release of insulin to keep blood sugar levels steady between meals and overnight.

Filling a pump with insulin

How it Works

• Continuous delivery - delivered by an insulin pump as a constant infusion or provided by long-acting insulin injections (e.g., Lantus, Levemir) taken once or twice daily.

• It mimics the body's natural insulin production to regulate glucose production by the liver and maintain steady blood sugar levels throughout the day and night.
  

Bolus Insulin

Bolus insulin is the additional insulin you take to cover the carbohydrates you eat (mealtime insulin) or to correct high blood sugar levels.

How it Works

• The mealtime dose is calculated based on the number of carbohydrates in your meal and your current blood sugar level to help control post-meal glucose spikes.

• A correction dose is used to lower high blood sugar levels back to the target range, usually calculated based on a correction factor provided by your doctor,
  

Bolus Insulin

• Rapid-acting insulin is injected or delivered through an insulin pump shortly before or after meals to manage post-meal blood sugar spikes (e.g., NovoLog, Humalog)
  

Combined Use

Many people with diabetes use both basal and bolus insulin to mimic the body's natural insulin production and maintain optimal blood glucose control.

• Basal Insulin provides a steady background insulin level.

• Bolus Insulin is an adjusted dose based on meals and correction needs throughout the day.

Understanding the difference between basal and bolus insulin is crucial for effective diabetes management. Properly balancing these two types of insulin doses helps maintain stable blood sugar levels, reduce the risk of complications and improve overall quality of life for individuals with diabetes.