When administering an intramuscular injection, what angle should the needle be inserted?

When administering an intramuscular injection, the needle should be inserted at a 90-degree angle to ensure the medication is deposited deep into the muscle tissue. This angle allows for proper penetration through the skin and subcutaneous tissue, placing the medication directly into the muscle, facilitating quicker absorption and more effective results.

Using a 90-degree angle ensures that the needle reaches the muscle fibers effectively without the risk of injecting into subcutaneous fat or other tissues, which could alter the action of the medication or lead to complications. An intramuscular route is particularly preferred for medications that require a fast onset of action or larger volumes.

Other angles, such as 45 degrees, 30 degrees, or 15 degrees, are not appropriate for intramuscular injections, as they would not effectively reach the muscle layer, potentially leading to inadequate drug absorption or inconsistent therapeutic effects.