Recommended Injection Site for Flu Shot in 4-Year-Olds
For a 4-year-old child, the flu shot should be administered intramuscularly in the deltoid muscle of the upper arm. 1
Site Selection by Age
At 4 years of age, children have transitioned from the infant/toddler injection site recommendations:
- Children ≥4 years: The deltoid muscle is the preferred site for intramuscular influenza vaccination 1
- Infants and young children <4 years: The anterolateral aspect of the thigh is preferred 1
The ACIP guidelines consistently specify that for "adults and older children, the deltoid is the preferred site," while "infants and younger children should be vaccinated in the anterolateral thigh." 1 The age cutoff where deltoid becomes preferred is at 4 years of age. 1
Dosing Considerations for 4-Year-Olds
- Dose volume: 0.5 mL per dose for all children ≥36 months (≥3 years) 1
- Number of doses: Most 4-year-olds will require only 1 dose per season, unless they are receiving their first-ever influenza vaccine and have never been vaccinated before, in which case 2 doses given ≥4 weeks apart are needed 1
Administration Technique
- Needle insertion: Administer at a 90-degree angle into the deltoid muscle 1
- Site preparation: Clean the injection site with an alcohol swab before administration 2
- Aspiration: Not required for vaccine administration at recommended injection sites, as no large blood vessels exist at these anatomically safe locations 3
Common Pitfall to Avoid
The most critical error would be continuing to use the anterolateral thigh site in a 4-year-old. While this was the correct site when the child was younger, the deltoid muscle is now sufficiently developed and is the guideline-recommended site at this age. 1