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by Schulte S
(IM Injection; Injection, IM; Injection, Intramuscular)


An intramuscular (IM) injection is a shot. The needle goes into the muscle to deliver medication. This is usually done by a doctor or nurse. Sometimes, your doctor may teach you to inject yourself. IM injections are deeper than injections given under the skin.

Intramuscular Injection
intramuscular injection
A needle passes through skin and fat layers into the muscle fibers to deliver medication.
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Reasons for Procedure

Some medications are better absorbed when given in the muscle. Other medications may be given in the muscle if you are unable to take them by mouth.

Some examples of medications given using an IM injection:

Possible Complications

Complications associated with IM injections are:

  • Bleeding, soreness, or redness at the injection site
  • Allergic reaction to the medication
  • Infection (rare)

What to Expect

Prior to Procedure

  • Make sure you have all of the items that you will need in front of you.
  • Make sure that you have the right medication and that it has not expired.
  • Wash hands with warm, soapy water before giving the injection.
  • Select a site for injection. This should be an area on your body with a large muscle, such as the thigh.
  • Cleanse the area with an alcohol wipe.

Description of Procedure

To inject yourself:

  • Remove the needle cap.
  • Smooth the skin with one hand.
  • Hold the syringe the way you would a pencil. Insert the needle at a 90° angle to the skin. The needle should be completely covered by skin.
  • Hold the syringe with one hand. With the other, pull back the plunger to check for blood in the syringe.
    • If you see blood, do not inject. Withdraw the needle and start again at a new site.
    • If you do not see blood, slowly press down on the plunger until it stops.
  • Remove the needle from the skin.
  • If there is bleeding at the site of injection, apply a bandage.
  • Immediately put the syringe and needle into a container that is puncture-proof.
  • Find out what services are available in your area for disposing of biological waste.

Will It Hurt?

Depending on the medication, there is usually some discomfort at the injection site. Soreness in the muscle is also common.

Tips for minimizing pain include:

  • Inject medication that is at room temperature.
  • Remove all air bubbles from the syringe before the injection.
  • Relax the muscles in the injection area.
  • Quickly break through the skin.
  • Do not change the direction of the needle as it goes in or comes out.
  • Do not reuse disposable needles.

Care After Injection

Follow your doctor's instructions regarding care required for the injection site.

Call Your Doctor

Call your doctor if any of the following occur:

  • Difficulty giving yourself the injection
  • A lot of pain
  • Medication is injected into the wrong area
  • Redness, swelling, increasing pain, excessive bleeding, or any discharge from the injection site
  • Rash or hives develop
  • Difficulty breathing
  • Fever

If you think you have an emergency, call for medical help right away.


Family Doctor—American Academy of Family Physicians  http://familydoctor.org 

National Institute of Allergy and Infectious Diseases  http://www.niaid.nih.gov 


Canadian Diabetes Association  http://www.diabetes.ca 

Health Canada  http://www.hc-sc.gc.ca 


Intramuscular injection (IM). Cincinnati Children's website. Available at: http://www.cincinnatichildrens.org/health/i/intramuscular-injection. Updated December 2013. Accessed August 27, 2014.

Lesson 2: Administer intramuscular injection. Brookside Associates Multimedia Edition website. Available at: http://brooksidepress.org/intramuscular/lessons/lesson-2-administer-an-intramuscular-injection. Accessed August 27, 2014.

Selecting, evaluating, and using sharps disposal containers website. Centers for Disease Control and Prevention website. Available at: http://www.cdc.gov/niosh/docs/97-111. Updated June 6, 2014. Accessed August 27, 2014.

Revision Information