If you’re no longer able to manage your diabetes condition with diet, exercise, and non-insulin medication, your doctor may prescribe insulin as the next step in your diabetes treatment plan. Insulin is a common treatment option for people with type 2 diabetes. Adding insulin to your treatment plan can help you gain better control over your blood sugar levels.

Many people with type 2 diabetes will eventually need insulin. The reason is that the body can simply stop making enough insulin to control blood sugar levels. "The cells that make insulin can be lost, so you have less insulin to work with," says Leann Olansky, MD, an endocrinologist at the Cleveland Clinic in Ohio. Another problem is that your body may no longer be able to effectively use the insulin it does make. When either of these problems occurs, your doctor will likely prescribe insulin.

Making the Decision to Add Insulin Medication

Your doctor will take into account a number of factors before recommending an insulin treatment plan. These include:

  • How high your blood sugar levels are
  • Other health conditions you have
  • Your age
  • Other medications you take
  • How much insulin your body is producing
  • How long you've had diabetes

Once your doctor decides that you need insulin to gain better control of your blood sugar, the next step is to determine the type of insulin you should use, how much you need to take, and when to take it.

More than 20 types of insulin are available in the United States. They vary in how fast they work, when they peak, how long they last, and how much they cost. For example, some insulin is fast-acting — it starts working within 15 minutes, peaks in about an hour, and lasts for up to 4 hours. Long-acting insulin, on the other hand, reaches the bloodstream more slowly after being injected and steadily controls blood sugar levels over the course of a day. Other types of insulin include short-acting and intermediate-acting.

For some people, one or two insulin injections each day are enough to keep blood sugar within a normal range. Others may need several injections a day. You'll work with your doctor to determine which type of insulin you need to use, how much, and how often. Keep in mind that your insulin dosages may need to be adjusted over time.

Setting Target Blood Sugar Levels

Once you start taking insulin, monitoring your blood sugar levels is important. Your doctor may need to adjust your dosage over time to make sure your diabetes is under tight control and that your blood sugar is kept as close to normal as possible.

For adults with diabetes, the American Diabetes Association recommends a normal pre-meal blood sugar range of 70 to 130 milligrams per deciliter (mg/dl) of blood. One to two hours after a meal has started, blood sugar levels should be less than 180 mg/dl.

Target blood sugar levels may vary from person to person and be more or less strict depending on a number of factors, such as:

  • How long you've had diabetes
  • Your age
  • Other health conditions you have
  • How well you understand the risks associated with taking too much insulin

Your doctor will offer guidance on what your personal target blood sugar level should be and how to manage your insulin regimen to keep your blood sugar balanced. By staying within your target range and avoiding big swings in your blood sugar levels, you can help prevent short-term problems like low blood sugar (hypoglycemia) and reduce the risk of serious long-term diabetes complications like heart disease and stroke.