Many people with type 2 diabetes need insulin therapy to help manage their blood sugar levels. If you need insulin therapy, starting it sooner rather than later can help lower your risk of complications.

Take a moment to learn more about insulin therapy and the factors that can affect your prescribed dosage.

1. Your doctor might prescribe basal insulin, bolus insulin, or both

  • Basal insulin. To help you maintain a low and steady level of insulin between meals, your doctor might prescribe background insulin replacement. They’ll advise you to take an injection of intermediate-acting or long-acting insulin once or twice a day. You can also use an insulin pump to give yourself a steady flow of rapid-acting insulin throughout the day.
  • Bolus insulin. To provide a surge of insulin after meals or as a correction for when your blood sugar is high, your doctor might prescribe bolus insulin replacement. They’ll advise you to take an injection of rapid-acting or short-acting insulin before you eat or when your blood sugar is high.

Some people with type 2 diabetes only need basal or bolus insulin replacement. Others benefit from a combination of both. Your doctor will advise you about which regimen is best for you.

2. If you’re prescribed basal insulin, you’ll take the same amount every day

If your doctor prescribes basal insulin, they’ll advise you to take a set amount of it each day. For example, they might ask you to take 10 units of long-acting insulin before bed each night.

If that isn’t enough to manage your blood sugar levels, they can prescribe more insulin. If your blood sugar management improves with time, they can reduce your dose. The amount of insulin will be adjusted based on your blood sugars.

3. If you’re prescribed bolus insulin, the amount you take will vary

If your doctor adds bolus insulin to your treatment plan, they’ll prescribe a certain ratio of rapid-acting or regular-actinginsulin to carbohydrates. This way your carb intake can be more flexible and you’ll adjust your mealtime insulin accordingly. Another option is to stick to a certain amount of carbs with each meal and take a fixed amount of insulin, though this approach offers less flexibility. 

In other words, you’ll have to match the amount of bolus insulin that you take to the amount of carbohydrates that you eat. If you plan to eat a meal that’s high in carbohydrates, you’ll need to take more bolus insulin beforehand. If you plan to eat a low-carb meal, you’ll take less bolus insulin beforehand.

You can also take bolus insulin to correct a high blood sugar. Your doctor will likely give you a “correction factor” to help you figure out how much insulin you need. This is also commonly known as a sliding scale.

4. Many factors affect the type and amount of insulin you need

Many factors affect the type and amount of basal or bolus insulin that you might need to take, including:

  • how much insulin your body produces on its own
  • how sensitive or resistant you are to insulin
  • how many carbohydrates you eat
  • how much exercise you get
  • how much sleep you get
  • how much you weigh
  • sickness or stress
  • alcohol intake
  • other medications, such as steroids

Any other medications you take for type 2 diabetes can affect how your body responds to insulin therapy, too. Weight loss surgery can also affect your insulin needs.

5. Your insulin needs can change over time

Changes to your treatment plan, lifestyle habits, weight, or overall health can affect how your body responds to your prescribed insulin regimen.

For example, if you lose weight, your doctor might be able to lower your prescribed insulin dose. If you adjust your diet to eat fewer carbohydrates, that can also reduce the amount of insulin that you need.

On the other hand, if you gain weight, your doctor might have to increase your prescribed insulin dose. If your body becomes more resistant to insulin, which happens with weight gain, that’ll also affect the amount of insulin that you need.

Always talk to your doctor before making any changes to your insulin regimen.

6. Blood sugar tests help you understand your insulin needs

To learn how well your current treatment plan is working, it’s important to test your blood sugar according to your doctor’s recommendations. For example, they’ll likely advise you to use home testing equipment to monitor and log your blood sugar each day. They’ll also order A1C tests, which provide information about your average blood sugar levels over the past three months.

If you find it hard to manage your blood sugar levels using your current treatment plan, talk to your doctor. They might recommend changes to your insulin regimen or other prescribed treatments.

The takeaway

If you’ve been prescribed insulin therapy, your healthcare team will work with you to ensure you have everything you need to use insulin effectively. They can also help you develop healthier lifestyle habits, which might reduce the amount of insulin you need.

Never make changes to your insulin regimen without talking to your doctor first. Following your prescribed treatment plan is vital to protecting your health and reducing your risk of complications from diabetes.