Injectable Insulin for Type 2 Diabetes: When, Why, and How

Most people with type 2 diabetes will eventually require insulin, and the transition is easier than you might think.

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you may be able to treat the condition with lifestyle changes, such as exercise and weight loss, and with oral medications at first, most people with type 2 diabetes eventually need to take insulin by injection.
It is possible to treat type 2 diabetes with lifestyle changes, but most people with the condition eventually need to take insulin by injection.iStock.com

Blood sugar control is one of the most important parts of type 2 diabetes management.

Although you may be able to treat the condition at first with oral medication and lifestyle changes, such as exercise and weight loss, most people with type 2 diabetes eventually need to take insulin by injection.

"There are several scenarios in which insulin treatment should start, including in patients with significant hyperglycemia who are symptomatic," explained Alaleh Mazhari, DO, an associate professor of endocrinology at Loyola Medicine in Maywood, Illinois.

"In these cases, the need for insulin may be short-term. Other situations include patients who are on multiple diabetic medications with uncontrolled diabetes, and uncontrolled diabetes in pregnancy, to name a few."

Do People With Type 2 Diabetes Have to Be on Insulin?

Do People With Type 2 Diabetes Have to Be on Insulin?

Here's what you need to know about taking insulin in the short term and the long term.

Insulin for Short-Term Blood Sugar Control

Doctors use a blood test called a hemoglobin A1C test to measure average blood sugar control over a two- to three-month period.

The treatment target for most people with diabetes is an A1C of 7 percent or less; those with higher levels may need a more intensive medication plan.

"The American Association of Clinical Endocrinologists recommends starting a person with type 2 diabetes on insulin if their A1C is above 9 percent and they have symptoms," said Mazhari.

Symptoms of type 2 diabetes include thirst, hunger, frequent urination, and weight loss.

Research published in February 2013 in the journal The Lancet Diabetes & Endocrinology reviewed several studies that focused on the temporary use of insulin to restore sugar control in people with type 2 diabetes.

The results showed that a two- to five-week course of short-term intensive insulin therapy (IIT) can induce remission in patients who are early in the course of type 2 diabetes. At three months after stopping the IIT, 66 percent of patients were still in remission, and at six months, 59 percent were still in remission.

Insulin for Long-Term Blood Sugar Control

"After 10 to 20 years, almost all patients with type 2 diabetes will need insulin," Mazhari said.

"Once they lose most of the cells in the pancreas that make insulin, no other diabetes medication can help. They may have been on one, two, or three diabetes medications, but their A1C can no longer be kept in a safe range."

Switching from numerous diabetes drugs to insulin can streamline your efforts.

Type 2 diabetes is a progressive disease, so treatment plans will change. When it's not possible to meet blood sugar control goals with lifestyle changes or other medication, insulin is the next step.

The change can have upsides, particularly for patients who have been on a complicated regimen of three or four drugs, with lots of side effects. Changing to insulin can actually be a lot better.

Making the Switch to Insulin

Making the transition is much easier than it used to be because most patients are started on a long-acting insulin that does not need to be matched with food intake.

Insulin pens that are preloaded are replacing insulin that needs to be drawn up into a syringe. Patients may still be worried about giving themselves injections, but because the needle is so tiny the adjustment is often quick.

Toujeo and Lantus are long-acting forms of insulin that are available in a prefilled injectable pen.

There's also a type of rapid-acting insulin, Afrezza, that can be inhaled through the mouth via an inhaler.

And a new class of medication called sodium-glucose cotransporter 2 (SGLT2) inhibitors is also available now, according to Mazhari. "It works via a different pathway that's not pancreas-dependent, offering another medical therapy option for patients with type 2 diabetes."

The key to an easy transition to insulin is education.

"Patients need to know how to take their insulin properly since there are many formulations on the market, including short- and long-acting insulin and premixed," Mazhari said. "Most can be started on a long-acting insulin once a day, though for some patients short-acting or mealtime insulin may be necessary as well. Insulin doses need to be further adjusted depending on blood sugar readings."

Important Insulin Basics

Dosing and Type Your dosing schedule and insulin type will depend on how advanced your diabetes is, plus your weight, age, level of physical activity, and the diabetic diet you're on. There's no "standard dose" for insulin.

Self-Testing Work with your team to come up with a blood sugar testing schedule at home. You may be instructed to check your blood sugar three or four times per day during the adjustment period.

Your healthcare team will use information about your fasting, pre-meal, and post-meal blood sugar levels to make changes to your insulin regimen.

Hypoglycemia Learn the symptoms of low blood sugar, or hypoglycemia, and what to do if you have them. The warning signs include feeling cold, shaky, dizzy, or confused. Symptoms can come on suddenly, so patients should know to drink a half-glass of juice, eat some hard candies, or chew some glucose tabs.

Treatment Team During the transition, stay in close contact with your treatment team. People starting insulin are often advised to meet with their health care providers on a weekly basis until blood sugars stabilize and the appropriate insulin dose is determined.

"The goal of type 2 diabetes treatment is to control blood sugar early, in order to prevent or delay the development of complications and, in those who already have them, to slow or halt their progression, if possible," said Mazhari.

"The earlier diabetes control is achieved, the better it is for the patient. Unfortunately, in those who already have complications, some of the damage is not reversible," said Mazhari. "We do our best to control diabetes using the available medications, including insulin, while working with patients to modify their diet and lifestyle."

"Obesity increases insulin resistance, but more activity and weight loss can lead to better insulin resistance and glucose control. In many cases this can help reduce the number or dose of the diabetic medication the patient is on, including insulin," Mazhari added.