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Insulin is a hormone produced by the pancreas that allows your body to absorb and use sugar (glucose) for energy. Insulin helps store glucose in your liver, fat, and muscles, and ultimately controls the amount of glucose in your bloodstream. If you are living with diabetes, insulin therapy may be necessary in managing your condition. The frequency, amount, type of insulin used, and the method of how you deliver insulin into the body can depend on the type of diabetes you have, lifestyle, preferences, and what is best to match the needs of your body.

Types of diabetes

There are different types of diabetes, which can impact dependence on insulin immediately upon diagnosis, or the need to add it in the future.

  • Type 1: For those living with type 1 diabetes, the pancreas is no longer able to produce insulin. For someone with type 1 diabetes, taking insulin is a requirement to survive.
  • Type 2: Individuals with type 2 diabetes are still able to make insulin, but their bodies may not utilize it properly. In addition to lifestyle changes, those with type 2 diabetes are often prescribed oral medications or other injectable medications that are not insulin. However, as type 2 diabetes progresses, an individual may need to take insulin to manage their blood sugar levels.
  • LADA (Latent Autoimmune Diabetes in Adults): This form of diabetes shares characteristics of both type 1 and type 2 diabetes and is diagnosed during adulthood. Initially, lifestyle and oral medications may be used to manage blood sugar levels, but eventually the pancreas will stop producing insulin altogether, which can take anywhere from a few months to several years, resulting in the need to take insulin.

The various types of insulin

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Insulin is categorized by how it enters and works in the bloodstream. It is helpful to understand how the insulin works, including the onset (the length of time before it begins to lower blood sugar,) the peak (the time when it is at its maximum effectiveness at lowering blood sugar levels,) and the duration (the length of time insulin continues to lower your blood sugar levels).

The type of insulin you need can depend on several factors, including your overall lifestyle, how your blood sugar shifts during the day, as well as the type of diabetes that you have.

The different types of insulin are:

  • Rapid-acting insulin: This will take effect about 15 minutes after an injection, it peaks in about 1 hour and continues to work lowering blood sugar for 4 hours.
  • Short-acting insulin: This will typically work within 30 minutes, peaks in the 2-3 hour range, and stays effective for 3-6 hours.
  • Intermediate-acting insulin: This type of insulin is working to help control glucose for 10-12 hours.
  • Long-acting and ultra-long acting insulin: This insulin can manage background glucose needs for up to 24-36 hours, though it can take several hours to enter the bloodstream.
  • Premixed/Combination insulin: This category of insulin contains a mix of rapid or short-acting insulin combined with an intermediate acting insulin.

Insulin also comes in different strengths, though the most common is U-100 (100 units of insulin per millimeter of fluid).

In addition, insulin can be categorized into how it functions by referring to basal and bolus insulin. Basal insulin is also often referred to as background insulin and provides the insulin needed between meals and while sleeping. Bolus insulin is used to cover carbohydrates consumed at mealtime and snacks, or if the blood sugar is above the target range and additional insulin is needed to lower the blood sugar.

How is insulin taken?

How and when insulin is taken is different for each person and can change over time. Insulin is delivered under the skin, and there are different methods it can be taken. Syringes with vials and insulin pens deliver insulin through a needle. There is also a form of insulin that can be administered by inhaling when rapid acting insulin is needed. Those on bolus and basal regimens can also use an insulin pump which delivers insulin through a thin plastic tube which is changed out by the user.

How much insulin, as well as what type you need, will vary. Your healthcare provider can help you determine the best course of insulin therapy for you.

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