Insulin Types & Action

Insulin Types &  Their Action

Here we give an overview of the different types and brand names of insulin available in Canada, plus details about their action time (how long each takes to start working, when it peaks, and how long it lasts).

All people with type 1 diabetes are “insulin dependent.” That is, we must take insulin by injection (syringe or pen) or infusion (insulin pump). Insulin cannot be taken by mouth because stomach acids will destroy it. Insulin helps sugar get into the body’s cells, which also helps children grow.

Brands of Insulin

Your child will be taking human insulin. It does not come from humans but is made in a laboratory. It is like the insulin our body makes. There are three companies that make insulin:


  • Eli Lilly (Humulin N® and Humalog®)
  • Novo Nordisk (Novolin ge NPH®, NovoRapid®, Fiasp® and Levemir®)
  • Sanofi Aventis (Lantus®, Apidra®)

Insulin Action

There are many types of insulin. They are differentiated by the way they act in terms of:

  • Onset (the length of time it takes to start working after injection/infusion);
  • Peak (the time at which insulin action is strongest); and
  • Duration (how long the insulin lasts).

Rapid-Acting Insulin

  • Clear
  • Onset: starts to work in approximately 15 - 20 minutes
  • Peak: strongest action at approximately 1 hour
  • Duration: lasts approximately 3-5 hours
  • Examples: Humalog® (insulin lispro), NovoRapid® (insulin aspart), Fiasp® (insulin aspart), Apidra® (insulin glulisine)
Waltzing The Dragon Inc
Rapid-Acting Insulin Curve

Note 1: “Rapid”-acting insulin may not act as rapidly as the name seems to suggest. It’s important to remember that rapid-acting insulin takes at least 15 minutes to even start having an effect, and it takes about an hour to peak. This has important implications for timing of insulin with food intake.

Note 2: NovoRapid® and Fiasp® have the same active ingredient (insulin aspart). However, Fiasp® also contains vitamin B3 (in the form of niacinamide), which speeds up how fast your body absorbs the insulin: it enters your bloodstream in approximately 2½ minutes (half as long as NovoRapid®). However, Fiasp® still takes about 15 minutes to start lowering your blood sugar (compared to about 20 minutes for NovoRapid®).

With a quicker onset and shorter tail, Fiasp® is currently the fastest-acting insulin available in Canada, which means you have more flexibility in how long (how short!) before eating you need to take it to minimize post-meal spikes.

Intermediate-Acting Insulin

  • Cloudy
  • Onset: starts to work in 2-4 hours
  • Peak: strongest action at 6-10 hours
  • Duration: lasts about 18 hours (up to 24 hours)
  • Examples: Humulin N®, Novolin NPH®
Waltzing The Dragon Inc
Intermediate-Acting Insulin Curve

Long-Acting (Basal) Insulin

  • Clear
  • Onset: starts to work in 60-90 minutes
  • Peak: none (provides a consistent concentration of insulin over the duration of insulin action)
  • Duration: lasts 12-24 hours
  • Examples: Lantus® (insulin glargine), Levemir® (insulin detemir)
Waltzing The Dragon Inc
Long-Acting Insulin Curve

Short-Acting Insulin

(or "Regular" insulin; an earlier generation of insulin, not commonly used today)

  • Clear
  • Onset: starts to work in about 30 minutes
  • Peak: strongest action at 2-4 hours
  • Duration: lasts approximately 4-6 hours
  • Examples: Humilin R®, Novolin Toronto®


The above information was adapted with permission from The Alberta Children’s Hospital Diabetes Clinic information handouts.

The above information was reviewed for content accuracy by clinical staff of the Alberta Children’s Hospital Diabetes Clinic.