Technically Speaking: Choosing the Proper Needle Length for Vaccination
Published on in Vaccine Update for Healthcare Providers
Published on in Vaccine Update for Healthcare Providers
Editor’s note: This is an updated version of the article originally published in August 2014.
Selecting the proper needle length when vaccinating your patients is critical — vaccine must reach the desired tissue site for optimal immune response to occur. To determine the proper needle length to use in each situation, you must consider the following factors:
Below is a summary of the guidance for choosing the proper needle length for intramuscular and subcutaneous injections based on CDC’s General Best Practice Guidelines for Immunization (Vaccine Administration).
Intramuscular (IM) injections: Injection site and needle size
Subcutaneous (Subcut) injections: Injection site and needle size
Intramuscular (IM) injections
The deltoid muscle is most often used as the site for IM injections in adults. Needle length is usually 1"–1½", 22–25 gauge, but a longer or shorter needle may be needed depending on the patient's weight.
Note: An alternate site for IM injection in adults is the anterolateral thigh muscle. The needle length and gauge are the same as when the deltoid muscle is used, i.e., 1"–1½” length, 22–25 gauge.
You should choose needle length based on the weight of your adult patients, as follows:
Subcutaneous (Subcut) injections
Contributed by: Deborah Wexler, MD
Categories: Vaccine Update July 2020, Technically Speaking
Materials in this section are updated as new information and vaccines become available. The Vaccine Education Center staff regularly reviews materials for accuracy.
You should not consider the information in this site to be specific, professional medical advice for your personal health or for your family's personal health. You should not use it to replace any relationship with a physician or other qualified healthcare professional. For medical concerns, including decisions about vaccinations, medications and other treatments, you should always consult your physician or, in serious cases, seek immediate assistance from emergency personnel.