Types of Insulin

Topic Overview

Insulin is used to treat people who have diabetes . Each type of insulin acts over a specific amount of time. The amount of time can be affected by exercise, diet, illness, some medicines, stress, the dose, and where the insulin has been injected.

Insulin strength is usually U-100, or 100 units of insulin in one millilitre of fluid. Short-acting (regular) insulin is also available in U-500, or 500 units of insulin in one millilitre of fluid. This is five times more concentrated than U-100 regular insulin.

Insulin is made by different companies. Make sure you use the same type of insulin consistently.

Types of insulin 1

Type

Examples

Appearance

When it starts to work (onset)

The time of greatest effect (peak)

How long it lasts (duration)

Rapid-acting

         
 

Apidra (insulin glulisine)

Clear

10–15 minutes

1–1.5 hours

3–5 hours

 

Humalog (insulin lispro)

Clear

10–15 minutes

1–2 hours

3.5–4.75 hours

 

NovoRapid (insulin aspart)

Clear

10–15 minutes

1–1.5 hours

3–5 hours

Short-acting

         
 

Humulin R, Novolin ge Toronto (insulin regular)

Clear

30 minutes

2–3 hours

6.5 hours

Intermediate-acting

         
 

Humulin N, Novolin ge NPH(insulin NPH)

Cloudy

1–3 hours

5–8 hours

Up to 18 hours

Long-acting

         
 

Lantus (insulin glargine)

Clear

1.5 hours

Does not apply

Up to 24 hours

 

Levemir (insulin detemir)

Clear

1.5 hours

Does not apply

16 to 24 hours

Rapid-acting insulins work over a narrow, more predictable range of time. Because they work quickly, they are used most often at the start of a meal. Rapid-acting insulin acts most like insulin that is produced by the human pancreas. It quickly drops the blood sugar level and works for a short time. If a rapid-acting insulin is used instead of a short-acting insulin at the start of dinner, it may prevent severe drops in blood sugar level in the middle of the night.

Short-acting insulins take effect and wear off more quickly than long-acting insulins. A short-acting insulin is often used 30–60 minutes before a meal so that it has time to work. These liquid insulins are clear and do not settle out when the bottle (vial) sits for a while.

Intermediate- and long-acting insulins contain added substances (buffers) that make them work over a long time and that may make them look cloudy. When these types of insulin sit for even a few minutes, the buffered insulin settles to the bottom of the vial. But insulin glargine (Lantus) and insulin detemir (Levemir) are clear liquids (not cloudy).

Mixtures of insulin can sometimes be combined in the same syringe, for example, intermediate-acting and rapid- or short-acting insulin. Not all insulins can be mixed together.

For convenience, there are premixed rapid- and intermediate-acting insulin. The insulin will start to work as quickly as the fastest-acting insulin in the combination. It will peak when each type of insulin typically peaks, and it will last as long as the longest-acting insulin. Examples include:

  • 30% regular and 70% NPH (Humulin 30/70, Novolin ge 30/70).
  • 50% lispro and 50% lispro protamine (Humalog Mix 50).
  • 25% lispro and 75% lispro protamine (Humalog Mix 25).
  • 30% aspart and 70% aspart protamine (NovoMix 30).

References

Citations

  1. Canadian Diabetes Association Clinical Practice Guidelines Expert Committee (2013). Pharmacotherapy in type 1 diabetes section of Canadian Diabetes Association 2013 clinical practice guidelines for the prevention and management of diabetes in Canada. Canadian Journal of Diabetes, 37(Suppl 1): S56–S60. Also available online: http://guidelines.diabetes.ca.

Credits

ByHealthwise Staff

Primary Medical Reviewer E. Gregory Thompson, MD - Internal Medicine

Anne C. Poinier, MD - Internal Medicine

Specialist Medical Reviewer David C.W. Lau, MD, PhD, FRCPC - Endocrinology

Current as ofMarch 11, 2014