Key Takeaways
- There are different types of insulin depending on how quickly they work, when they peak and how long they last.
- Insulin is available in different strengths; the most common is U-100.
- All insulin available in the United States is manufactured in a laboratory, but animal insulin can still be imported for personal use.
Insulin Basics
The insulin your body makes is made by the beta cells inside your pancreas. Your beta cells are found in clusters of cells in your pancreas called the Islets of Langerhans. When you eat, your beta cells release insulin to help your body use blood glucose (blood sugar) as fuel for energy right away or store it for later use.
What are the most common forms of insulin?
There are different types of insulin and different ways to take it. Insulin can be taken as a liquid by injection or by using an insulin pump. It can also be inhaled in powder form through a special device. Insulin can’t be taken as a pill because your stomach acid would break it down like food.
- Liquid insulin comes in different strengths. The most common type used is U-100, which means it has 100 units of insulin in each milliliter. Stronger insulins, like U-500, can be used if you have severe insulin resistance. All insulins made in the United States are analog insulins, meaning that they’re synthetic forms of human insulin.
- Insulin powder comes in cartridges of units, but the strength isn’t exactly the same as the liquid U-100 insulin. Read more about a recent study with inhaled insulin for children and teens here inhaled insulin study in children and adolescents.
- Animal insulin, made from beef or pork, was once commonly used, but is no longer made in the U.S. If you need to take animal insulin, talk with your doctor about options to have it imported.
What types of insulin are there and how do they work?
Types of Insulin | ||
|---|---|---|
| The different types of insulin are based on how quickly it starts working (onset), when insulin is at its maximum strength (peak), and how long the insulin stays active in your body (duration). | ||
| Rapid-Acting Onset: about 15 minutes Peak: about 1–2 hours Duration: about 2–4 hours | Rapid-Acting Inhaled Onset: about 10–15 minutes Peak: about 30 minutes Duration: about 1.5–3 hours | Short-Acting Onset: about 30–60 minutes Peak: about 2–3 hours Duration: about 3–6 hours |
| Intermediate-Acting Onset: about 2-4 hours Peak: about 4–12 hours Duration: about 12–18 hours | Long-Acting Onset: about 1.5–4 hours Peak: No peak Duration: about 24 hours | Ultra Long-Acting Onset: about 6 hours Peak: No peak Duration: about 36+ hours |
What is the difference between bolus and basal insulin?
Bolus insulin is taken to cover rising blood glucose levels, usually from meals.
Basal insulin, sometimes called background insulin, is insulin that works through the day and night to manage blood glucose. Basal insulin can be rapid-acting insulin delivered steadily with an insulin pump, or long-acting insulins that have longer onsets and durations.
The Bottom Line
You can find more information about insulin on our Insulin Routines page.
Talk to your healthcare team about the insulin and delivery options that will work best for your treatment plan. Be sure to discuss your risk for low blood glucose (hypoglycemia) and how to manage ketones as part of your plan.
