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12.1 Administering Oral Medications

Oral medications may be administered via the oral, sublingual, buccal, or feeding tube route. Before administering oral medications, it is important for the nurse to consider the preparation of the medication because preparation has implications for how the medication should be administered. By following the steps of oral medication administration, ensuring the medication “rights” are confirmed at the three checkpoints, and following appropriate delegation procedures, the nurse may ensure safe administration of oral medications.

12.2 Administering Parenteral Medications

Parenteral medications are injected directly into the tissues and circulatory system, thus bypassing the gastrointestinal tract. Administering medications parenterally eliminates the effects of first-pass metabolism, allows for faster onset, and provides stronger effects than oral medications. Common routes for parenteral medication administration include intramuscular, subcutaneous, intravenous, and intradermal. When administering parenteral medications, it is essential to ensure the safety of both the patient and the nurse. Guidelines for ensuring safety include confirming the medication rights and protecting sterility. These guidelines also ensure that the appropriate procedures for administration are followed, which include cleansing the site, engaging needle safety devices, and ensuring proper disposal of needles. When administering parenteral medications, the nurse is responsible for gathering the necessary equipment, including syringes, needles, or needleless systems. The equipment used will depend on a number of factors, including the type of medication, location of injection, amount of medication required, and the size of the patient.

12.3 Preparing Unit-Dose Packaged Medications

Vials store liquid or powder medications that are administered via the parenteral route. They may be single-use (used one time for one patient) or multidose in which a dose may be administered to one or more patients. When removing medication from a vial, always check the expiration date before use, remove the plastic cap, and wipe the rubber stopper with an alcohol swab. Inject air equivalent to the desired dose into the vial before withdrawing the medication.

Ampules are small glass containers that hold a single dose of liquid medication. Caution must be taken to prevent cutting yourself on the broken glass. A filtered needle must be used to withdraw the medication, and the ampule must be disposed of in the sharps container. Medications also may come prepared in prefilled cartridges, such as injector devices and prefilled syringes. Other medications may come supplied as a powder and require a liquid to be added to reconstitute the medication into a solution form that would be suitable for parenteral administration. Medications may be mixed in one syringe if they are compatible and the total volume does not exceed the maximum volume for the site of injection. Long-acting insulins may never be mixed.

12.4 Administering Intradermal Injections

Intradermal medications are injected into the dermis. The ID route has the most prolonged absorption time of the various parenteral routes because there are fewer blood vessels and no muscle tissue available to distribute the medications. Common sites for ID injections include the anterior surface of the forearm, posterior surface of the upper arm, the upper back and under the scapula, and upper chest. A variety of medications may be administered intradermally, including Botox injections, allergy testing, steroids, local anesthesia, and TB testing.

Intradermal injections are administered at a 5- to 15-degree angle, using a 26G to 27G gauge needle that is 0.25 to 0.5 in (6.4 to 13 mm) long. Prior to injecting the medication, the nurse holds the skin taut, inserts the needle into the skin with the bevel up, and slowly injects the medication. Presence of a wheal confirms placement into the dermis.

12.5 Administering Subcutaneous Injections

Subcutaneous medications are injected beneath the skin into the adipose tissue. Medications administered via this route have a slow, sustained rate of absorption because of a lack of blood vessels found within the tissue. The most commonly used sites include the outer portion of the upper arm, the upper back, the abdomen below the costal margin to the iliac crest no closer to the umbilicus than 1 in (2.5 cm), the upper ventral gluteal region, and the anterior thigh. A variety of medications may be given subcutaneously, including narcotics, antiemetics, heparin, fertility medications, and insulin. Subcutaneous injections are administered at a 45- to 90-degree angle, using a 25- to 30-gauge needle that is 3/8 to 5/8 in (9.5 to 16 mm) long. Before injecting the medication, grasp or pinch the skin to pull the adipose tissue away from the muscle. Inject the needle into the skin using a quick, dart-like motion and slowly inject the medication at a rate of approximately 10 seconds per mL.

12.6 Administering Intramuscular Injections

Intramuscular medications are injected directly into the muscle. Medications administered via the IM route may be absorbed faster than those injected via the SQ or ID routes because of the increased blood supply found within muscles. Common sites for IM injections include the deltoid, vastus lateralis, and ventrogluteal muscles, depending on the patient’s age, condition, type of medication to be administered, and volume of medication required. The IM route is preferred when larger volumes of fluids are required or the solution is concentrated, viscous, or oil based. A variety of medications may be given intramuscularly, including narcotics, antibiotics, vaccines, immunoglobulins, and hormonal medications.

Intramuscular injections are administered at a 90-degree angle, using a 5/8 to 1.5 in (13 to 38 mm) long, 18G to 25G needle, depending on the patient’s body composition and amount of adipose tissue, age, type of medication, amount of the medication to be administered, and viscosity of the medication. Before injecting the medication, hold the skin or use the Z-track method to secure the area for the injection. Aspirate (if required by agency policy) by pulling back on the plunger to check for blood return, then slowly inject the medication at a rate of approximately 10 seconds per mL, unless otherwise indicated.


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