Source : http://www.health.gov.nl.ca/health/publications/immunization/S4/

Reference for IM Injection : NB Immunization Handbook, appendix XVI

Administering an IM injection to a child

Infants 18 months and less :

Vastus lateralis muscle (anterolateral surface of the thigh)

25 gauge, 5/8 to 1 inch needle

Have parent hold infant sideways in a cuddle/semi-recumbent position on lap

Parent can restrain outer arm. Place inside arm behind parents back

Legs can be placed in between parent’s knees, or held by parent

Vastus lateralis located on most lateral aspect of thigh

Is free of major nerves and blood vessels

To locate, divide area from top of femur to top of knee into 3 parts

Landmark a site in middle third of outer thigh

Children 18 months and over

Deltoid muscle, 25 gauge, 5/8 to 1 inch needle

Place child sideways on parent’s lap

Injection arm is held close to child’s body

Free arm is place behind parent’s back

Child’s legs can be place in between parents knees

Landmark by imagining injection site in middle of upside down triangle

with base at lower edge of acromial process, point opposite to axilla

Palpate acromial process; place 4 fingers across deltoid with top finger on acromial process;

this leaves 3 fingers lying below the acromial process

At bottom of the 4th finger in middle of muscle is the injection site

Care is needed to avoid the acromion, clavicle, humerus, brachial veins/arteries and radial nerve

Adults

Deltoid muscle, 25 gauge, 1 inch needle

May need to use 11/2 inch on larger adults ( e.g. overweight, large muscle)