Insulin Therapy

Insulin Therapy

Some people who have type 2 diabetes need insulin therapy as well. Because normal digestion interferes with insulin taken by mouth, insulin must be injected.

Insulin injections involve using a fine needle and syringe or an insulin pen injector — a device that looks like an ink pen, except the cartridge is filled with insulin.

There are many types of insulin one of the most important differences is the duration of action. 

Rapid-acting insulin is often called mealtime insulin, since it is used around 15 minutes before having a meal. The rapid-acting insulin is necessary to cover the increased need for insulin after a meal.

Short-acting insulin normally starts working after 30 to 60 minutes. Depending on the insulin product its effect lasts for about eight hours.

Most of the insulin used nowadays, are so called human insulins. In contrast to the once commonly used animal insulin this insulin is produced in the lab. They act similarly to the insulin that is produced in a healthy pancreas. In recent years, also the so-called analog insulins have been developed. Because of their  exchanged or changed order of small protein modules they are somewhat better used therapeutically. Their effects kicks in quicker than those of the rapid acting human insulins.

The intermediate-acting insulin normally kicks in around 1 to 3 hours after injection can last up until 16 hours.

The long-acting insulin normally starts working after 60 to 120 minutes. Its effects last from 20 to 26 hours. Long-acting insulin simulates the basic supply of insulin, in particular those of the liver. This type of basic supply of insulin is also called basal insulin.

Insulin type Generic and brand names Onset Peak Duration
Rapid-acting Insulin aspart (NovoLog) Insulin glulisine (Apidra) Insulin lispro (Humalog) 15 minutes 30 to 90 minutes 3 to 5 hours
Short-acting Insulin regular (Humulin R, Novolin R) 30 to 60 minutes 2 to 4 hours 5 to 8 hours
Intermediate-acting Insulin NPH human (Humulin N, Novolin N) 1 to 3 hours 8 hours 12 to 16 hours
Long-acting Insulin glargine (Lantus) Insulin detemir (Levemir) 1 hour No clear peak 20 to 26 hours

Depending on your needs, pre-mixed insulin — a combination of specific proportions of intermediate-acting and short- or rapid-acting insulin in one bottle or insulin pen — may be an option.

Nevertheless one has to keep in mind that none of the insulin products can reproduce the exact physiological situation of a non-diabetic person. Hence, your doctor has to decide individually, which type of insulin or which combination of different types is most useful to a patient. When to use which type of insulin depends on the therapy the doctor decides to follow.

The Conventional Insulin Therapy

When you are following a conventional insulin therapy then you are most likely to inject two times a day a mixture of normal and long-acting (intermediate) insulin. It will be decided based on insulin dosage, injection time, amount and time of day as well as physical activity. These factors should be kept as stable as possible.

The Intensive Insulin Therapy

If you have type 1 diabetes — and in some cases if you have type 2 diabetes — intensive insulin therapy may be the key to long-term health.

This aggressive therapy isn’t easy, but the benefits are real.

What is intensive insulin therapy?

Intensive insulin therapy is an aggressive treatment approach designed to control your blood sugar levels. Intensive insulin therapy requires close monitoring of blood sugar levels and frequent doses of insulin. Intensive insulin therapy can prevent or slow the progression of long-term diabetes complications.

If you choose to try intensive insulin therapy, you’ll work with your doctor to set various goals. Ideally, this means:

  • Blood sugar level before meals: 70 to 130 milligrams per deciliter (mg/dL), or 3.9 to 7.2 millimoles per liter (mmol/L)
  • Blood sugar level two hours after meals: less than 160  mg/dL (10 mmol/L)
  • Hemoglobin A1C (glycated hemoglobin, an indicator of your blood sugar control for the past few months): less than 7 percent