Insulin: What You Need to Know
Experts believe even more people with type 2 should take insulin to control blood glucose - the earlier, the better.
If you live long enough with type 2 diabetes, odds are good you'll eventually need insulin," says William Polonsky, Ph.D., CDE, assistant clinical professor in psychiatry at the University of California, San Diego, and author of Diabetes Burnout: What to Do When You Can't Take It Anymore. The decision to start insulin isn't easy. How do you know if you need to take it, and, if you do, what's the best way to start? Before you and your doctor make a decision, find out the latest on insulin.
Insulin and Taking Control
Insulin In Your Body
Research has shown that type 2 diabetes naturally progresses as your body produces less and less insulin. Your beta cells - the cells in the pancreas that produce insulin - slowly lose function. Experts believe that by the time you're diagnosed with type 2 diabetes, you've already lost half of your beta cell function. And the loss continues. "About six years after being diagnosed, most people have only about a quarter of their beta cell function left," says Anthony McCall, M.D., Ph.D., endocrinologist and James M. Moss Professor in Diabetes at the University of Virginia Health System. "With this minimal function, the need for injected insulin increases." Some experts believe initiating insulin early in the course of type 2 diabetes can lower blood glucose and even preserve some beta cell function.
Insulin resistance is another health issue common in people with type 2 diabetes. It refers to your body's inability to effectively use the insulin you make, which complicates blood glucose control.
To stay healthy with type 2 diabetes, your goal should be metabolic control of blood glucose, blood lipids, and blood pressure. To control blood glucose, you need to match your diabetes care to your body's waning supply of insulin. At diagnosis, some people still produce enough insulin to hit their blood glucose targets by eating healthfully, getting physical activity, and losing weight. Others need to start diabetes medications and/or insulin right away. As the body gradually produces less insulin, nearly everyone with type 2 diabetes needs diabetes medication and/or insulin. When you go on insulin, you will still need to eat healthfully and be physical active most days.
Dealing With Fear
The Fear Factor
Many people are afraid to start taking insulin. "This is the moment at which diabetes becomes real," Polonsky says. "Some believe that starting insulin means their health will worsen. Others fear the injections themselves or are anxious about the disruptions, inconveniences, and changes taking insulin will cause." A few people worry about hypoglycemia
(when blood glucose falls below 70 mg/dl and you feel dizzy or shaky). It happens, but it's rare in people with type 2 diabetes.
Polonsky, who speaks internationally to health care providers about effective ways to help people start insulin, believes doctors often escalate these fears by positioning the need for insulin as a punishment for a patient's failure to make lifestyle changes to control blood glucose. In reality, the problem is beta cell failure that happens naturally during the course of diabetes. It is not from failing to follow a healthful diet.
Face Your Fears
Be honest with your health care providers about any concerns you have about taking insulin. "Get the facts you need about taking insulin in the 21st century," McCall suggests. He believes many fears are due to dated knowledge.
Esther Workman is an A1C Champion, a spokesperson in a program that encourages people with type 2 diabetes who've achieved an A1C of less than 7 percent to help others gain glycemic control. Esther has taken insulin for 15 years. When her doctor told her she needed insulin, he said, "The fear is worse than the fact." With these words, Esther says she "just did it and found taking insulin to be no big deal." She advises, "Keep your eyes on the prize - blood glucose control and your health."
When to Start
How do you know you need insulin, and how should you start taking it? "You need insulin if your A1C is higher than 6.5 or 7 percent, despite eating healthfully, being active, and taking diabetes pills in effective doses," McCall says. "Doctors should get people started on insulin in a timely fashion." If your diabetes is out of control (blood glucose levels above 250 mg/dl and A1C above 9), then insulin is the only therapy that will lower your blood glucose levels enough. If you gain better control, you may be able to manage without insulin for a while.
How to Start
You may begin with a simple regimen, such as one injection of intermediate- or long-acting insulin at night or a combination insulin at breakfast and supper. "Talk frequently with your doctor or request guidelines for adjusting your insulin dose until you achieve blood glucose control," Polonsky encourages. Eventually, you may need a more complex regimen that more closely mimics the way your pancreas releases insulin.
What About Your Pills?
Should you stay on your diabetes pills when you start taking insulin? Doctors have varying opinions. Many agree that you should stay on the pills that treat insulin resistance, such as metformin (Glucophage) or a glitazone (Avandia or Actos). Some doctors suggest you stop taking pills that work by helping your pancreas produce more insulin, such as sulfonylureas, others don't. If you don't improve, ask questions.
Types of Insulin
Insulin has come a long way in the past 15 years. There are now four main types - some bolus, some basal. They differ in their action curve: the onset (when insulin starts to lower blood glucose); the peak (when it lowers blood glucose the most); and duration (how long the effect lasts). Bolus insulin covers blood glucose rise from food. Basal insulin covers between-meal and overnight blood glucose levels. People generally need half of their insulin as bolus and half as basal. The four main types are: Rapid-acting: This bolus insulin works quickly, helping to control glucose levels during and just after meals. Common names are lispro (Humalog), aspart (NovoLog), and glulisine (Apidra).
- Short-acting or regular: This bolus insulin takes longer to lower blood glucose than rapid-acting. It was the only bolus insulin prior to 1995 and is used less now.
- Intermediate-acting: This works slower and lowers blood glucose levels throughout the day to cover both basal and bolus needs. The common names are NPH (Humulin N and Novolin N) and lente (Lente).
- Long-acting: This controls blood glucose levels throughout the day to cover basal needs. Ultralente was the first in this category, but, in 2006, it will no longer be produced. Glargine (Lantus) was introduced in 2001. Detemir (Levemir) was approved by the FDA in 2005 and will be available later in 2006. Both are taken once or twice a day.
In addition, several combinations of insulin are available with varying amounts of bolus and basal insulin to control blood glucose and make taking insulin simpler. People typically take one dose before breakfast and another before supper.
How you take insulin is your choice. For shots, your grandmother's glass syringes and big needles are long gone. Now plastic syringes, fine needles, and other devices make it easier. If you choose the traditional vial and syringe, pick the size syringe and needle that are right for you.
Insulin pens come with single and combination insulins. You place a thin, short needle on the pen for each injection. To select a dose, you turn a dial, then press a plunger to deliver the insulin. Pens are convenient to carry and provide accurate dosing.
Insulin pumps available today are open-loop pumps, meaning they don't contain a glucose sensor to measure blood glucose levels. The open-loop pumps use just rapid-acting insulin, which is delivered under the skin (the same as injections) continuously to meet basal insulin needs and when you eat to meet bolus needs. Rather than taking multiple injections each day, you change the infusion set every two or three days. More people with type 2 diabetes are now going on insulin pumps.
Talk to your doctor, diabetes educator, or pharmacist about your options.
The Future of Insulin
A glimpse into the crystal ball reveals that more insulin advances are percolating. There will be new insulins, such as the long-acting insulin detemir. Improvements will be made in the open-loop pumps currently on the market, and efforts will continue on implantable, closed-loop pumps.
Work progresses on alternate ways to take insulin. Exubera, being reviewed by the U.S. Food and Drug Administration, is a dry powder to be inhaled through the mouth. It's a short-acting insulin for mealtimes. Investigation is ongoing for delivering insulin buccally - via the tongue, throat, and cheeks - or a skin patch.
While the progress on new insulin products and delivery systems is encouraging, don't delay getting started on insulin if your doctor and your diabetes health status indicate you need it now. The insulins available today are safe, relatively easy to take, and less painful than ever. Plus, starting to take insulin sooner rather than later may improve your health fairly quickly and make your life better for many days and years to come.
10 Guidelines for Starting Insulin
- Know your doctor's plan up front. Ask what A1C and blood glucose measures she uses and how she would get you started on insulin.
- Think short term, not long term. Start taking insulin when your doctor recommends it and see whether you feel better and have more energy.
- Ask to be referred to a diabetes education program to learn the ins and outs of taking insulin.
- Have a plan with your health care professional to increase your dose until you hit your blood glucose targets.
- Get the inside scoop by talking to people who have successfully transitioned to insulin.
- Explore your options for insulin delivery. Check what your health plan covers.
- Continue to eat healthfully and to get regular physical activity.
- Strive for consistency. Take your insulin and eat at similar times every day to the extent possible.
- Store insulin properly. Keep the pen or vial of insulin in use at room temperature and keep extras in the refrigerator.
- Carry a source of carbohydrate to treat low blood glucose - Glucose tablets or hard candy. Start with 15 grams of carbohydrate.