How to Safely Administer an Intramuscular Vaccine in Adults

We all know how important vaccines are, but do you know that how you administer them can affect patient safety? This article reviews how to prevent vaccine-related injuries by using the right supplies and techniques. Nurses Safety Article

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How to Safely Administer an Intramuscular Vaccine in Adults

Have you seen a nurse eyeball a vaccine site before giving an injection? Does it make you think twice? Do you know that if a vaccine is not given in the correct location of the deltoid muscle, a vaccine-related shoulder injury or nerve injury could occur? To prevent vaccine-related shoulder and nerve injuries, it is important for the nurse to use the correct supplies, landmarking, and technique. This article will review how to:

  • Gather the right supplies
  • Use aseptic technique
  • Landmark the injection site
  • Administer the vaccine

Gather the Right Supplies

Start by gathering your needle and syringe. To avoid using a needle that is too short or too long, assess the patient's weight. This is important because a needle that is too short will inject into subcutaneous tissue, and a needle that is too long could hit bone or the axillary nerve. The CDC recommends using a one-inch 22- to 25-gauge needle for men 130-260 lbs and women 130-200 lbs. For patients who weigh under 130 lbs, use a 22 to 25-gauge 1-inch or a ⅝ inch needle for those with an especially small frame. For men greater than 260 lbs and women greater than 200 lbs, use a 22- to 25-gauge 1.5-inch needle. A 1 mL or 2 mL syringe can be used. Draw up your vaccine as indicated and gather any other supplies you will need, such as gloves, rubbing alcohol prep, gauze, and adhesive bandage.

Use Aseptic Technique

Before touching the patient, wash your hands with soap and water or use an alcohol-based hand sanitizer. To wash your hands, rub them together with soap and water for at least 15 seconds. Make sure you wash all surfaces of your hands. Rinse and use paper towels to dry. If using alcohol-based hand sanitizer, put sanitizer on hands and rub onto all surfaces until fully dry. Put on gloves.

Landmark the Injection Site


The deltoid muscle in the upper arm is the recommended injection site for most vaccines. Administering the injection too high in the deltoid muscle can cause a shoulder injury, and administering too low could hit the radial nerve. To give the vaccine safely, it is essential that the nurse locate the correct injection site. The deltoid muscle is located in the upper arm and has a triangular shape. To find the injection site, you will need to ask the patient to expose their shoulder completely. Make sure the patient's sleeve can be rolled up over the shoulder or removed. To locate the injection site, palpate the top of the shoulder, starting at the clavicle and moving toward the shoulder joint. You will feel a bony prominence where the clavicle meets the acromion process. The small flat part of the bone just beyond this bony prominence is the acromion process (see illustration). This is the point you will use to measure to the middle or thickest part of the deltoid muscle, which is located approximately 2 inches below the acromion. You can measure using your finger widths. Depending on the size of your fingers, 2 to 3 finger widths are approximately 2 inches. Starting at the acromion, rest 2 to 3 fingers on the shoulder and note the location. This will be your injection site. The injection site should be along the midline of the shoulder. It should also be above the armpit or axillary fold.

Administer the Vaccine

Once you have found your injection site, cleanse the site with your alcohol prep and allow it to dry. Ask the patient to relax their arm along their body and take a deep breath. Some nurses like to start a conversation to keep the patient relaxed. There is no need to pinch or stretch the skin. Insert the needle at a 90-degree angle using a smooth, swift motion. Do not aspirate. Inject the vaccine and dispose of the needle and syringe in an appropriate sharps container. Use your gauze or adhesive bandage as needed. Remove your gloves and perform hand hygiene.

Following these recommended guidelines will help ensure the vaccine is effective and keep your patients safe and injury free! 


Shoulder injury related to vaccine administration (SIRVA)

Shoulder injury related to vaccine administration and other injection site events

Katherine is an R.N., B.S.N. with experience in medical-surgical, cardiac, and gastrointestinal nursing. She enjoys writing health content about a variety of topics. When she is not writing, you can find her in the kitchen cooking for her hungry teenage boys or attending one of their sporting events.

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Specializes in Med nurse in med-surg., float, HH, and PDN.

How do you tell a pharmacist that she gives the vaccines too high on the shoulder? 

Specializes in Neurosurgery, Pediatric Transplant, OB.

Great article! Thanks for sharing.

Specializes in ICU.

I appreciate the clear importance that you pointed out about landmarks. This is key when giving injections in the muscle ? 

Specializes in Clinical Research, Outpt Women's Health.
No Stars In My Eyes said:

How do you tell a pharmacist that she gives the vaccines too high on the shoulder? 

Leave them a copy of the article ?

I'm so glad you added "do not aspirate". A huge controversy was created around aspiration without any evidence. 

Specializes in Surgical Specialty Clinic - Ambulatory Care.

"Do not stretch or pull the skin" So z-track is not good practice anymore more? Why not? Just curious as it is my favorite thing to do.


Also thank you for the weight and needle length recommendations 

Specializes in Health Writer, Registered Nurse.

I saw many nurses giving vaccines so low in the arm when the vaccine clinics were in affect.  Thank you for a refresher article for those who may have not given IM injections in a while.

Specializes in Licensed Practical Nurse.

According to the recommendations of the World Health Organization (WHO) and the US Advisory Committee on Immunization Practices (ACIP), intramuscular vaccination is performed as follows:

Holding your hand on the shoulder of the vaccinated person, carefully hold and stretch between your thumb and forefinger the area where the Injection will be performed 2-3 fingers below the shoulder process of the scapula,
With a firm, quick motion, insert the syringe needle at a right angle (90°) to the skin surface,
Gently and steadily press the plunger of the syringe, at the same time be careful that the needle does not move in the tissues,
After administering the entire volume of vaccine, pull out the needle in a decisive motion in a line perpendicular to the skin surface (at the same angle at which it was inserted),
Do not rub the injection site, a clean gauze pad can be applied to the skin after injection.