Two common ways injections are given are intramuscular (IM) and subcutaneous (subcut) injections.
Intramuscular Injections (IM)
IM injections deliver medication directly into a muscle. This method allows for faster absorption of the medication compared to subcutaneous injections. Common injection sites include the deltoid muscle in the upper arm, the vastus lateralis muscle in the thigh, and the gluteus maximus muscle in the buttock. The specific site chosen depends on factors such as the age and size of the patient, and the volume of medication being administered. https://www.drugs.com/article/injection-types-sites.html provides further information on injection sites.
Subcutaneous Injections (Subcut)
Subcutaneous injections deliver medication into the fatty tissue layer just beneath the skin. This method is often used for medications that don't require rapid absorption. Common injection sites include the outer aspect of the upper arm, the anterior thigh, and the abdomen. Smaller volumes of medication are typically administered subcutaneously compared to intramuscular injections. The CDC provides detailed guidance on vaccine administration routes and sites, including subcutaneous injections. https://www.cdc.gov/vaccines/hcp/admin/administer-vaccines.html
Other injection methods exist, such as intravenous (IV) and intrathecal injections, but IM and subcut are the two most commonly encountered methods for routine medication administration.
