When administering a subcutaneous injection, how should pharmacists position the needle?

When administering a subcutaneous injection, the most appropriate angle for the needle insertion is typically at a 45-degree angle. This angle allows for effective delivery of the medication into the subcutaneous tissue, which is the layer of fat and connective tissue just beneath the skin.

Positioning the needle at a 90-degree angle is more commonly associated with intramuscular injections, where the muscle beneath the skin needs to be reached. Subcutaneous injections, however, require a more shallow angle to ensure that the medication is placed in the correct tissue layer without going too deep into the muscle. A 45-degree angle helps minimize the risk of injecting into muscle and ensures that the desired absorption occurs from the fatty layer, which is essential for many vaccines and medications administered subcutaneously.

Choosing a different angle, such as horizontally against the skin, does not facilitate proper insertion into the subcutaneous layer and could lead to vaccine efficacy issues or discomfort for the patient.