Types of Insulin

Types of Insulin


Insulin is used to treat people who have diabetes. How quickly insulin starts to work and how long it lasts will be different depending on the type of insulin you use. Other factors that can affect insulin and your blood sugar are exercise, diet, illness, some medicines, stress, the dose, how you take it, or where you inject it. The table below is a general guide. Your results may be different.

Insulin is available in several strengths. U-100 is the most common. U-100 means there are 100 units of insulin in one millilitre of fluid. Other strengths include U-200, U-300, and U-500. For example, U-500 is five times more concentrated than U-100 regular insulin. Be sure to check the concentration of your insulin so you take the right amount.

Insulin is made by different companies. Ask your doctor or diabetes educator about the type of insulin you have and how to use it. See the table below for types of insulin and some examples. footnote 1

Types of insulin
Type Examples Appearance When it starts to work (onset) How long it lasts (duration)
Rapid-acting insulins (bolus insulin) are usually taken at the start of a meal.

Insulin aspart (NovoRapid)

Insulin glulisine (Apidra)

Insulin lispro (Humalog)

Clear 4–20 minutes 3–5 hours
Short-acting insulins (bolus insulin) are usually taken a short time before a meal.

Insulin regular (Entuzity, Humulin-R, Novolin ge Toronto)

Clear 15–30 minutes 6.5–24 hours
Intermediate-acting insulins (basal insulin) are usually taken between meals and at bedtime.

Insulin NPH (Humulin-N and Novolin ge NPH)

Cloudy 1-3 hours Up to 18 hours
Long-acting insulins (basal insulin) are usually taken between meals and at bedtime.

Insulin detemir (Levemir)

Insulin glargine (Lantus)

Clear 90 minutes 16–24 hours
Ultra long-acting insulins (basal insulin) are usually taken between meals and at bedtime.

Degludec (Tresiba)

Insuline glargine (Toujeo)

Clear 90 minutes 30–42 hours

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 insulins. These come in a premixed ratio such as 25/75, 30/70, 40/60, and 50/50. For example, 25/75 means the mixture is 25% rapid-acting insulin and 75% intermediate-acting insulin. They are usually taken 2 times a day at the start of a meal. These insulins look cloudy. The insulin will start to work as quickly as the fastest-acting insulin in the combination. It will last as long as the longest-acting insulin. Examples include:

  • Insulin regular and insulin NPH.
  • Insulin lispro and insulin lispro protamine.
  • Biphasic insulin aspart.



  1. Diabetes Canada Clinical Practice Guidelines Expert Committee, et al. (2018). Types of insulin. Canadian Journal of Diabetes, 42(Suppl 1): S314. DOI: 10.1016/j.jcjd.2017.12.006. Accessed November 16, 2018.


Current as of: March 1, 2023

Author: Healthwise Staff
Medical Review:
E. Gregory Thompson MD - Internal Medicine
Kathleen Romito MD - Family Medicine
Adam Husney MD - Family Medicine
David C.W. Lau MD, PhD, FRCPC - Endocrinology
Rhonda O'Brien MS, RD, CDE - Certified Diabetes Educator
Caroline S. Rhoads MD - Internal Medicine