If you’re considering insulin to manage type 2 diabetes, odds are you’ve already tried diet, exercise, and oral medicines. If these aren't keeping your blood sugar level in a healthy range, your doctor might have recommended starting insulin.

Insulin therapy isn’t as simple as giving yourself a daily injection and watching your blood sugar levels go down. Any number of factors can change your body’s need for insulin, from the kinds of food you eat to how much you exercise. Insulin also comes in different forms. Some types start to work quickly but don’t last long. Others get to work more slowly but last for hours.

Based on your health, lifestyle, and blood sugar goals, your doctor will help you decide which type of insulin is best for you and how often to give yourself injections. When it comes to taking insulin, consistency is key. Changes to your dose, diet, and exercise can throw off your blood sugar control. Once your doctor sets a routine for you, it’s important that you stick with it.

Here’s what to expect as you and your doctor establish your insulin routine.

Choosing an insulin type

Insulin comes in four types, based on how long it takes to start working, how long it takes until it gets to the highest level in the body — the peak — and how long its effects last:

  • Rapid-acting insulin takes 5 to 15 minutes to start working, peaks after about an hour, and lasts 2 to 4 hours.
  • Short-acting insulin takes 30 to 45 minutes to start working, peaks between 2 and 3 hours, and lasts 3 to 6 hours.
  • Intermediate-acting insulin takes 2 hours to start working, peaks between 4 and 12 hours, and then lasts 12 to 18 hours.
  • Long-acting insulin takes 2 hours to start working, doesn’t have a peak, and lasts about 24 hours.

You might need to take a combination of these types depending on how much insulin your body makes and how well it works. For example, you might take long-acting insulin once or twice a day only, or you may add rapid-acting insulin before meals and when you need it to bring down high blood sugar. Or you might combine insulin with an oral medicine.

Fine-tuning your dose

Your doctor will prescribe an insulin dose for you. You’ll also need to calculate some of your doses based on your daily blood sugar readings and the number of carbohydrates you eat.

Other factors can also influence your blood sugar levels, and how much insulin you need. These include:

  • exercise
  • illness
  • stress
  • kidney function

Ask your doctor how to adjust your dose based on these and other factors.

Testing your blood sugar

The only way to know if your blood sugar is within range, and if you need to adjust your insulin dose or timing, is to test it. Ask your doctor how often to check your blood sugar.

Typically, people with type 2 diabetes test their blood sugar once or twice or even more each day — usually first thing in the morning, possibly before meals, and possibly before bedtime. You might also need to test before and after exercise, or when you’re stressed or sick. All of these factors can affect your blood sugar levels.

Picking a delivery method

When it comes to giving yourself insulin, you have a few delivery choices:

  • A syringe is a hollow tube with a needle on one end.
  • Insulin pens contain a cartridge of insulin that either comes prefilled or that you fill yourself. You dial the dose into the pen, and then inject insulin through the needle.
  • Insulin pumps streamline the process by automatically delivering insulin into your skin through a thin plastic tube called a catheter. You can program the pump to deliver continuous small doses of insulin throughout the day and larger doses around mealtimes. These are more common for those with type 1 diabetes.
  • Jet injectors don’t use a needle. Instead, they use high pressure to push a spray of insulin through your skin.

Your doctor will help you decide which method to use based on the costs, your preferences, and your lifestyle.

Staying on your insulin routine

Here are a few tips to help you stick with your insulin routine:

  • Keep track of your numbers. Knowing how your blood sugar fluctuates throughout the day and day to day will make it easier to manage. Each time you test your blood sugar, write the results in a journal or keep them in an app like mySugr or BG Monitor on your phone. Share your results with your doctor.
  • Follow your schedule. Test your blood sugar and give yourself insulin at the times of day your doctor recommended. Changing your schedule can throw off your blood sugar control.
  • Watch your food choices and portion sizes. Excess carbs can hijack your blood sugar control. Try to keep your carb count steady so you can balance it with your insulin needs. A carb-counting app like Carb Counting with Lenny might help you track your carb intake.
  • Stay in touch with your medical team. If you’re having trouble managing your blood sugar levels, talk to your doctor or diabetes educator. You might need to adjust your insulin dose or diet.

If you find that you can’t stick with your routine or your blood sugar numbers aren’t staying within range, see your doctor. You might need to fine-tune your insulin dose, timing, or other parts of your routine.