Injections are used in a variety of medical settings and applications to administer medications, vaccines, or other substances directly into the body. The specific location of injection depends on the type of injection and the medication being administered.
Types of Injections and Their Locations:
- Subcutaneous Injections: These injections are administered into the fatty tissue just beneath the skin. Common sites include the fatty tissue behind the upper arm, the abdomen, or the thigh. Examples include insulin injections and some vaccines. [Reference: Subcutaneous injections may be administered in the fatty tissue behind the upper arm, in the abdomen, or in the thigh. Certain medications, including epinephrine, may be used either intramuscularly or subcutaneously. Others, such as insulin, are almost exclusively injected subcutaneously.]
- Intramuscular Injections: These injections are given into a muscle. The anterolateral thigh is a common site for adults, using a needle length adjusted for skin tightness. [Reference: For injections in the anterolateral thigh, use a 1½" needle for adults of any weight. Alternate needle lengths may be used if the skin is stretched tightly and...] Other sites may be used depending on the medication and the patient's age and condition.
- Intravenous Injections: These injections deliver medication directly into a vein, providing rapid absorption into the bloodstream.
- Intradermal Injections: These injections are administered into the dermis (the layer of skin below the epidermis). They are often used for allergy testing or skin testing.
- Intravitreal Injections: These injections are administered directly into the vitreous humor of the eye, and are used to treat various retinal conditions such as age-related macular degeneration (AMD) and diabetic retinopathy. [Reference: Intravitreal injections are used to administer medications to treat a variety of retinal conditions. Age-related macular degeneration (AMD), diabetic...]
- Intraosseous Injections: These injections are administered directly into the bone marrow, usually in emergency situations where intravenous access is difficult.
- Injection Wells: In industrial settings, injection wells are used to place fluids underground, such as carbon dioxide for long-term storage. [Reference: An injection well is used to place fluid underground into porous geologic formations. These underground formations may range from deep sandstone or limestone,...]
Examples of Injection Uses:
- Vaccines: Many vaccines are administered via subcutaneous or intramuscular injection. [Reference: Vaccines available in the United States are administered by 4 routes: Oral Route (PO): Oral vaccine is administered through drops to the mouth.]
- Medications: Many medications are administered via injection, particularly those that need rapid absorption or cannot be taken orally. Examples include insulin, steroids, and pain relief medications. [Reference: Side effects of steroid injections · pain and discomfort for a few days – paracetamol may help with this · temporary bruising or a collection of blood under the...]
- Cosmetic Procedures: Botox injections are commonly used for cosmetic purposes to reduce wrinkles. [Reference: Wrinkle-reducing treatments that use botulinum toxin injectables may also be used to treat chronic migraines ...]
