What Are the Best Intramuscular Injection Sites?

Intramuscular (IM) injections are shots delivered to a large muscle. The shot can be given by a healthcare provider or self-administered to any one of four injection sites on the body. IM injections are used for people of all ages, including infants.

Some IM injection sites may be preferred over others, depending on the age of the recipient, the type of medication used, the dose, the intramuscular needle size, and whether the shot is being given to yourself or by someone else. Choosing the right site is important as it helps reduce the risk of injury and ensures that the medicine is properly absorbed.

Self-administered IM injections may be used for different reasons, including assisted fertility treatments, gender-affirming hormone therapy, vitamin B12 supplementation, and some disease-modifying treatments for autoimmune diseases like rheumatoid arthritis.

The article lists the four sites commonly used for intramuscular injections and provides instructions on how to give the shots safely. It also discusses the right injection technique as well as possible side effects. 

Where Are the Four Intramuscular Injection Sites?

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

Upper Arm

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

To find the injection site, feel for the bone at the top of your arm where your arm meets your shoulder. The injection site is about two inches below that spot (or roughly two or three finger widths). Be sure to give the injection in the center of the muscles where it is thickest.

It can be difficult to give yourself a shot in the deltoid muscle. You may need help from a partner.

Thigh

Your vastus lateralis and rectus femoris muscles are located in your thigh. They make up what is known as the quadriceps (quad) muscle.

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.

Buttock

The dorsogluteal muscle is the large muscle located in your buttocks. It is one of the largest muscles on the body but one that can be awkward to access on your own. For this site, you will need a partner.

To find this site, divide one butt cheek into fourths from top to bottom and side to side. Your partner will want to give the injection in the outer, upper quadrant toward the hip. This is the part of the buttocks with the least fatty tissue.

Hip

Your ventrogluteal muscle is located near your hip. While it is possible to give yourself a shot there, it may be easier to do with a partner.

To find the 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.

Proper Technique for IM Injections

Your healthcare provider will give you a prescription for your IM medication as well as for the appropriately sized syringes and needles. The gauge of the needle is especially important as small needles can fail if the injectable medication is thick.

A nurse or other healthcare provider will teach you or your partner how to deliver the injections. It is important that you are comfortable with the technique before doing it yourself.

If you are concerned about pain, you can numb the injection site for five to 10 minutes with ice. There are also numbing creams, typically containing lidocaine, available at most drugstores.

To give yourself or your partner an IM injection:

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.
    

Possible Side Effects

There may be temporary pain and discomfort during the IM injection itself, but these tend to ease quite quickly. There also be minor bleeding, pain, swelling, or redness following the shot.

If you give yourself an injection in the dorsogluteal site, there is a risk of sciatic nerve injury. This can lead to a painful condition called sciatica that tends to resolve on its own but can make you uncomfortable for several days or weeks. Significant bleeding is also possible.

Although unlikely, it is possible to get an infection from an IM injection. This can occur if you do not adhere to hygienic practices (like washing your hands), reuse needles or syringes, or use medications that are expired or look tainted.

Summary

There are four sites on your body that can be used to give yourself an intramuscular 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

The idea of giving yourself an intramuscular injection can make you squeamish, but, with practice, most people become quite comfortable doing so. As with anything, practice makes perfect. While you're getting the hang of it, you can practice by giving shots to an orange.

The main thing to remember is not to "stab" the needle but to give the shot with a brisk, controlled movement. To do so, you need to hold the syringe firmly. If you don't, you'll have less control when administering the shot and may end up bouncing the needle off of the skin.