Insulin injections are a necessary part of insulin therapy, but where you inject insulin is not something to take lightly. Injection sites and insulin injection techniques can have an impact on the effectiveness of insulin therapy as well as your comfort levels. This blog post will walk you through how to choose the best insulin injection site for you and how to inject insulin into that site correctly.

In this Diabetic & Me article you will learn about:

  • What is the best injection site?
  • How and why rotate your injection sites?
  • Where should I not inject insulin?

What is the best injection site for insulin?

The best injection site for insulin is the abdomen. Injecting insulin on the stomach will ensure the insulin reaches your bloodstream quickly since there is no fatty tissue in that area to slow down absorption. You can also inject insulin in your thigh or buttocks, but these areas of the body may not absorb as quickly as the stomach or arm. However, injecting insulin in these areas can give you a sense of comfort since you'll be able to see the needle before it goes into your skin. If you feel more comfortable with a particular site, then stick with that one. It's important to inject into all areas of your body, but be aware that injections in some sites may require more force and pressure than others.

Insulin Injection Sites

1. Abdomen

When insulin is taken by injection, it is usually injected subcutaneously (under the skin), just below the fatty tissue.

If you inject insulin into your abdomen then your hemoglobin can use it more efficiently because insulin that travels with your blood has better access to the body's cells in the intestine, muscle, and other tissues where glucose occurs more often. 

2. Upper Arms

The upper arms are also a good place for insulin injections because insulin injections in this area could produce less swelling.

The injection point can be easily accessed to provide insulin if needed. There is less risk of jostling the insulin when injecting it as well, which reduces chances for air bubbles coming up in the insulin. There is also a reduced risk of creating bruises on this injection site and also evenly distributes insulin.

3. Thighs

For insulin injection sites, a good insulin injection site is in the thighs. It's better to inject insulin in the thighs because insulin is a protein and the muscles of your thighs weigh more than other areas so it absorbs insulin even better.

4. Lower back, hips, or buttocks

Insulin injection sites are a very personal choice, but insulin in the lower back, hips, or buttocks is generally the preferred insulin injection site for people with diabetes. Lower insulin injection sites were once more popular because it's easy to inject insulin quickly and it is less painful than areas such as the stomach or upper legs. 

How do I take an insulin injection?

Below you can find a few steps on how to inject insulin.

  • Wash your hands with soap and water before injecting insulin. This is not always possible when you are not home or in a place where you can't wash your hands.
  • Gather all the necessary supplies needed for injecting insulin including insulin, syringe(s), alcohol swabs, and needles. If you are using an insulin pump you will need to follow the steps according to your pump.
  • Select the site where you're injecting insulin by either injecting it into the lower back, upper legs, hips, or buttocks. Lower injection sites are usually preferred due to less pain and quick injection time.
  • Clean the injection site with an alcohol swab before injecting.
  • Inject your insulin slowly to prevent bumps.

Where should you not inject insulin?

Avoid sites that you plan on exercising as this can increase the risk of hypoglycemia due to increased absorption. Avoid injecting into areas of your skin, moles, or scar tissue, as these can also affect insulin absorption. If you develop lumps and bumps at injection sites, avoid the area of the bump for several months because that area will absorb insulin differently and this can affect your blood sugar levels.

Also, try to avoid places that you can't easily reach or places where your skin doesn't allow you to be pricked by a needle.

How to rotate your insulin injection site?

Insulin injection sites and how to inject insulin are a personal choice but it's important that you rotate your insulin site and technique as this can help avoid any build-up of insulin in one spot which may affect blood sugar levels.

The best way to rotate your insulin spots is to alternate injecting insulin into the lower back, upper legs, hips, or buttocks.

Below you can find a rotation scheme that you can use to rotate your injection sites.

Insulin Injection Rotations Sites

What happens if you don't rotate insulin injection sites?

If you often inject insulin in the same place, a thickening can develop under the skin. This creates scar tissue, as it were, often palpable as a small bump, sometimes also visible. Because the subcutaneous tissue is damaged, the insulin is not absorbed properly or very unpredictably. This usually increases the insulin requirement. These subcutaneous thickenings are referred to by the following names: injection site, injection infiltrate, lipodystrophy, lipoatrophy, or in short; lipos.

To prevent thickenings at the injection site, you are advised to change the injection site each time, both between the left and right side of the body and between the abdomen, thighs, flanks, and buttocks. Within an injection site, for example, the left side of the abdomen, you can give each injection with a finger width difference from the previous one. It is also good to use a new needle with each injection.

Can I Reuse My Syringe?

If you use your needle or syringe multiple times, there are the following risks:

  • The tip of the needle becomes blunt after just one use, the sliding layer on the tip may become worn and the tip of the needle may be deformed:
    • injections hurt more.
    • very small skin lesions or bruising may occur.
  • The pen needle is no longer sterile after first use:
    • reuse is unhygienic.
    • the risk of infections increases.
  • The insulin can crystallize in the pen needle:
    • the needle can become blocked, preventing safe insulin delivery is possible.
    • dosing errors are therefore possible and unexpectedly high blood glucose levels.
  • Formation or expansion of air bubbles in the ampoule:
    • the insulin may drip from the needle (during storage).
    • the insulin dosage becomes inaccurate.

Related article: How To Reduce Injection Site Bruising


Insulin injection sites are a very personal choice, but injecting insulin into the lower back, hips, or buttocks is generally preferred for people with diabetes. Lower injection sites were once more popular because it's easy to inject insulin quickly and less painful than areas such as the stomach or upper legs. However, injecting in these places can increase your risk of hypoglycemia due to increased absorption so you should avoid injecting into any area where you plan on exercising. 

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About the Author

Ely Fornoville

Hi, I'm Ely Fornoville, and I am the founder of Diabetic Me. Being a type 1 diabetic since 1996, I developed a passion to help people learn more about diabetes. I write about diabetes and share stories from other diabetics around the world. I currently use a Medtronic Guardian 4 CGM and a MiniMed 780G insulin pump with Humalog insulin.

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