What is an intramuscular injection?

An intramuscular (IM) injection is the injection of a medication into a muscle. An IM injection may be recommended because large muscles have more blood vessels in them than skin tissue. This enables faster absorption of the drug.

Where do you give an intramuscular injection?

The best sites for an intramuscular injection are: Deltoid muscle of the shoulder Vastus lateralis muscle on the outside of the thigh Rectus femoris muscle on the front of the thigh Dorsogluteal muscle on the upper buttock Ventrogluteal muscle on the hip just above the dorsogluteal muscle

How do you give an intramuscular injection?

To give an intramuscular injection, either to yourself or someone else: Gather your supplies. Wash your hands. Clean the injection site with an alcohol swab. Remove the cap from the needle. Push the needle through the rubber seal on top of the vial. Draw back the plunger to fill the syringe. Withdraw the needle from the vial. Remove any air bubbles by gently tapping the syringe and compressing the plunger. Holding the syringe like a dart, position the needle at a 90-degree angle to the injection site. Insert the needle with a brisk, controlled motion. Compress the plunger to inject the drug. Remove the needle. Apply pressure to the injection site with some gauze. Discard the needle and syringe safely.

When is an intramuscular injection avoided?

For people with a severe bleeding disorder or low platelet count , intramuscular injections may be avoided due to the risk of bleeding. They may also not be appropriate for people with hypovolemic shock or muscle wasting as these conditions may affect drug absorption.

The Best Injection Sites for an Intramuscular Injection

If you're undergoing assisted fertility treatment, you may need to give yourself shots.

When you give yourself a shot, it's important to choose the right injection site on your body. This will help ensure that the medicine is absorbed the way it should be. It will also help prevent injury.

Woman using an Insulin injection — IAN HOOTON / Getty Images

Fertility shots are given intramuscularly (IM). This means the shot is given in the muscle. Your muscles are located under a layer of insulating fat.

At first, the idea of giving yourself shots may seem overwhelming. With preparation and practice, though, it can become quick and painless.

This article looks at the best sites for intramuscular injection. It also discusses the right injection technique and possible side effects.

Where Are the Four Injection Sites?

There are four sites you can use to give yourself a shot. These sites have large, easy-to-locate muscles with little fatty tissue.

Upper Arm

Your deltoid muscle is in your upper arm, just below your shoulder.

To find this site, feel for the bone at the top of your arm where your arm meets your shoulder. The injection site is about 2 inches below that spot. This should be equal to two or three finger widths. Make sure to give the injection in the center of this part of your upper arm.

Note that it can be difficult to give yourself a shot in this site. You may need help from a partner.

Thigh

Your vastus lateralis and rectus femoris muscles are located in your thigh.

To find these muscles, imagine lines dividing the front of your thigh into thirds from the top to the bottom.

To inject into the vastus lateralis, the needle should go into the middle third on the outer portion of your thigh. To inject into the rectus femoris muscle, the needle should go in the middle third at the front of your thigh.

Hip

Your ventrogluteal muscle is located near your hip.

For injections in this site, you'll need a partner to do the injection for you. To find this site, lie on your back and have your partner stand facing your hips.

Have your partner place the heel of their hand so that their wrist is lined up with your thigh. Your partner's thumb should be pointed toward your groin and their fingers should be pointed toward your head.

They should be able to feel the border of a bony area with their ring finger and pinkie. Next, your partner should spread their pointer finger and middle finger into a V and give the injection between those fingers.

Buttocks

The dorsogluteal muscle is the large muscle located in your buttocks.

This injection site should also be accessed with the help of a partner. To find this site, divide one butt cheek into fourths, with two fourths side by side at the bottom and two on top. You will always want to give the injection in the outer, upper quadrant, almost toward the hip.

Learning Injection Technique

Your healthcare provider will give you a prescription for your medication. You will also receive a prescription for the syringes and needles.

A nurse or other healthcare provider can help you learn how to give yourself shots. You may be asked to watch a video or practice on a doll. It is important to make sure you are comfortable with the technique before you start doing it yourself.

There are a few ways to make sure your injections are safe and painless. This includes:

Numbing the area beforehand with ice
Selecting your injection site carefully

Make sure to carefully feel for your selected muscle before giving yourself an injection. Find a comfortable position and try to relax your muscle as much as possible.

How to Choose the Right Needle to Give Yourself an Injection

It is a good idea to alternate sites with each injection. This will help you avoid swelling and soreness.

Some people may have an injury, wound, or other reason to avoid certain injection sites. If this is you, your healthcare provider may recommend a particular site for your shots.

Recap

A nurse or other healthcare provider can help you learn to give yourself a shot. Make sure you are comfortable with the technique before you try doing it yourself.

Possible Side Effects of Injections

Watch out for side effects. These could include:

Pain
Redness
Swelling
Warmth
Pus or drainage at the injection site

Report any concerns to your healthcare provider or nurse.

Summary

There are four sites on your body that can be used to give yourself an injection. These include the upper arm, thigh, hip, and buttocks.

Make sure you are comfortable with the injection technique before you start giving yourself shots. A nurse or other healthcare provider can show you how to do it.

Look out for side effects and report any concerns to your healthcare provider.

A Word From Verywell

Not all injections are intramuscular. Some conditions require other types of injections, such as subcutaneous. Subcutaneous injections are given in the fat layer just under the skin.

Conditions that require other types of injections include:

Multiple sclerosis, an autoimmune disease that affects the nerves
Diabetes, a condition that causes high blood sugar
Nutritional deficiencies

If you have already learned to give yourself IM injections, you should be able to learn to give other types. This could be helpful if you have loved ones that need to inject medication for a health condition.

Frequently Asked Questions

What is an intramuscular injection?

An intramuscular (IM) injection is the injection of a medication into a muscle. An IM injection may be recommended because large muscles have more blood vessels in them than skin tissue. This enables faster absorption of the drug.
Where do you give an intramuscular injection?
The best sites for an intramuscular injection are:
- Deltoid muscle of the shoulder
- Vastus lateralis muscle on the outside of the thigh
- Rectus femoris muscle on the front of the thigh
- Dorsogluteal muscle on the upper buttock
- Ventrogluteal muscle on the hip just above the dorsogluteal muscle
Learn More: Overcoming Your Fear of Self-Injection
How do you give an intramuscular injection?
To give an intramuscular injection, either to yourself or someone else:
1. Gather your supplies.
2. Wash your hands.
3. Clean the injection site with an alcohol swab.
4. Remove the cap from the needle.
5. Push the needle through the rubber seal on top of the vial.
6. Draw back the plunger to fill the syringe.
7. Withdraw the needle from the vial.
8. Remove any air bubbles by gently tapping the syringe and compressing the plunger.
9. Holding the syringe like a dart, position the needle at a 90-degree angle to the injection site.
10. Insert the needle with a brisk, controlled motion.
11. Compress the plunger to inject the drug.
12. Remove the needle.
13. Apply pressure to the injection site with some gauze.
14. Discard the needle and syringe safely.
Learn More: How to Reduce Injection Pain
When is an intramuscular injection avoided?

For people with a severe bleeding disorder or low platelet count, intramuscular injections may be avoided due to the risk of bleeding. They may also not be appropriate for people with hypovolemic shock or muscle wasting as these conditions may affect drug absorption.