Maximum Volume for Deltoid Intramuscular Injection
The standard maximum volume for deltoid intramuscular injection is 0.5 mL for children aged 3 years and older and adults, with some vaccines using 0.25 mL for younger children (6-35 months). 1
Volume Guidelines by Age
Infants and Young Children (6-35 months)
- 0.25 mL or 0.5 mL depending on the specific vaccine product 1
- For Fluzone: both 0.25 mL and 0.5 mL doses demonstrate comparable safety and immunogenicity 1
- For Afluria: 0.25 mL is the recommended dose from multidose vials 1
- Important caveat: A 0.5 mL prefilled syringe should never be split into two 0.25 mL doses due to sterility concerns 1
Children ≥3 Years and Adults
- 0.5 mL is the standard dose volume for intramuscular vaccines 1
- This volume applies to Fluarix, FluLaval, and Flucelvax products 1
Anatomical Site Selection
Preferred Injection Location
- Deltoid muscle is the recommended site for older children and adults 1
- The anterolateral thigh should be used for infants and young children instead 1
Needle Length Considerations
- Adults and older children: needle length >1 inch may be needed, as needles <1 inch might be insufficient to penetrate muscle tissue 1
- Children with adequate deltoid mass: 7/8 to 1.25 inches is recommended 1
Critical Safety Considerations
The volume limit of 0.5 mL in the deltoid is based on vaccine administration guidelines, which represent the most extensively studied intramuscular injections in this site. While these guidelines specifically address vaccines, they establish the practical upper limit for deltoid injection volumes in clinical practice.
Why Volume Matters
- Larger volumes risk inadequate muscle penetration and subcutaneous deposition 1
- The deltoid has limited muscle mass compared to larger injection sites like the vastus lateralis 2
- Excessive volume can cause local pain, reduced absorption, and increased adverse reactions 1
Alternative Sites for Larger Volumes
- For volumes exceeding 0.5 mL, consider the anterolateral thigh (vastus lateralis), which accommodates larger volumes and provides more rapid absorption for certain medications 2
- The gluteal region is another option for larger volumes, though it has fallen out of favor for routine use