Dr. MJ Bazos MD,
Insulin Regimens for People with Type 1 Diabetes
What is insulin?
Insulin is a hormone that controls the level of
sugar (also called glucose) in your body. When you have type 1 diabetes, your
body doesn't make enough insulin. This causes sugar to build up in your blood.
Over time, high blood sugar levels can cause serious health problems, such as
blindness, kidney problems, and damage to the nerves in your legs and feet. It's
very important for you to keep your blood sugar level as close to normal as
possible. If you do this, you can avoid or delay many of the serious health
problems caused by diabetes.
How do I use insulin?
Types of insulin
Rapid-acting, such as insulin lispro (
brand name: Humalog); this insulin starts to work very quickly (within 15
minutes) and lasts for 3 to 4 hours. A similar kind of insulin is insulin aspart
(brand name: Novolog).
Short-acting, such as Regular (R)
insulin; this insulin starts working within 30 minutes and lasts about 6 to 8
hours. It reaches its peak in 2 to 4 hours.
Intermediate-acting, such as NPH (N) or
Lente (L) insulin; this insulin starts working in 1 to 3 hours and lasts 16 to
Long-acting, such as Ultralente (U)
insulin; this insulin doesn't start to work for 4 to 6 hours but lasts 24 to 28
hours. It reaches its peak in 8 to 10 hours. A new insulin, called insulin
glargine ( brand name: Lantus), lasts for 24 hours but has no
Because your body doesn't make enough insulin,
you must give yourself insulin with injections, an insulin pen or an insulin
pump. There are different kinds of insulin (see box at right). They all start
working and keep working at different speeds. Your doctor will talk with you
about what insulin to use. Your doctor might want you to use more than one kind
of insulin every day. Some insulins can be mixed together.
What is a flexible insulin
A flexible insulin regimen lets you adjust when
you take insulin and how much you use. With a conventional regimen, you take
insulin at set times and have to follow a strict schedule. A flexible regimen
allows for changes in your schedule and lets you adjust your insulin dose as
needed. For example, you might increase the dose of insulin if you eat a meal
with a lot of carbohydrates. Or you might lower your insulin dose if you're
going to exercise. A flexible regimen also may help you keep tighter control
over your blood sugar level. A flexible insulin regimen has benefits, but it
means you'll have to make some extra effort. You must check your blood sugar
level regularly and keep track of what you eat (this means counting the grams of
carbohydrates you eat). You must also learn how your body reacts to insulin and
how to adjust your dose. Too much insulin can give you a condition called
hypoglycemia (blood sugar level is too low). Too little insulin can give you
hyperglycemia (blood sugar level is too high). Both of these conditions can be
dangerous to your health.
When should I take insulin?
Your doctor or the health care team will talk
with you about when to take insulin. Remember that some insulins start working
faster, while others keep working longer. It's important to pay attention to the
time between taking insulin and eating a meal. For example, regular insulin has
to be taken 20 to 30 minutes before eating. Insulin lispro starts working
faster, so it should be taken no more than 15 minutes before eating a meal.
Why should I count carbohydrates?
Carbohydrates are the main nutrients that affect
your blood sugar level. For this reason, they can change the amount of insulin
you need to take. Your doctor or someone in your diabetes care team can teach
you how to count grams of carbohydrates and how to adjust the amount of insulin
you take, depending on what you eat.