Medication Administration > Chapter 2

Chapter II. Routes of Medication Administration

There are several different routes to administer medication. These include:
  • oral
  • topical
  • inhaled
  • parenteral

Oral medications

Administering drugs by the oral route is the safest and most convenient method of administering medications. Oral medications can be administered via the mouth, or they may also be administered into a feeding tube that is placed in the stomach or jejunum. If the patient isn't able to swallow water or fluids, or has nausea and vomiting, medications are usually not administered by the oral route. In some instances, medications may be administered by the sublingual or buccal route.

Oral administration

To administer an oral medication, first place the patient in a sitting position. Having the patient sit up in a chair or in the bed helps decrease the risk of aspiration of the fluid used to administer the medication. Have the patient drink a large enough volume of liquid to make sure that the medication moves smoothly through the esophagus and into the stomach. Some medications, such as alendronate (Fosamax), are very irritating to the esophagus if they become lodged and can cause serious problems. If the patient feels that a medication is lodged in his throat, offer a small amount of a soft food, such as bread or banana, to help move the medication into the stomach (Craven, 2009).

If you have a patient who is able to swallow soft foods, but can't easily swallow whole capsule or tablets, there are several techniques that you can use to help the patient. Some capsules can be opened and the contents placed on a soft food, such as applesauce or pudding. Many tablets can be crushed and placed on a soft food. Never crush a sustained or extended released tablet, because this will affect the availability of the medication. If you are unsure whether a medication can be opened or crushed, check with the pharmacist.

Administration through tubes

At times, you may administer medication through a tube directly into the stomach or jejunum. The medication may be administered through a nasogastric or gastric tube, or a percutaneous tube. When you are using a small-bore feeding tube to administer the medication, you must be careful to avoid the patient aspirating, and also clogging the administration tube. To decrease the risk of aspiration, place the patient in a high-Fowler's position. If the patient isn't able to tolerate a high-Fowler's position, the head of the bed should be raised to at least a 30-degree angle. Keep the patient upright for at least 30 minutes after administering the medication.

If you are administering a tablet through a tube, crush the tablet into fine particles and dissolve it in warm water. Flush the tube with at least 30 ml of warm water before and after administering the medication to help decrease the risk of clogging the tube (Craven, 2009). Again, never crush extended or sustained release medications.

Sublingual and buccal administration

The sublingual and buccal administration routes permit rapid absorption of medication and avoids first-pass metabolism that can break down the drug (Aschebrenner, 2009). The most common drug that is given by the sublingual or buccal route is nitroglycerin.

To administer a sublingual tablet, place the tablet under the patient's tongue. Instruct the patient not to bite or swallow the tablet. Also, direct the patient not to eat or drink anything until the medication is completely dissolved.

If you're administering a buccal medication, place the tablet in the pouch between the patient's cheek and gums. Again, instruct the patient not to bite or swallow the medication, or to drink or eat anything until the medication is dissolved.

Topical administration

Topical drugs work after being applied to a patient's skin or mucous membranes. Topical drugs may be a lotion, cream, ointment, paste, powder, or spray.Topical drugs are usually used for their local, not systemic, effects.

Lotion, creams, and ointments

Lotions, creams, and ointments are used to treat a skin problem or wound. They are among some of the simplest medications you will administer. Clean and dry the skin before applying any medication to it. Lotions and creams are rubbed into the skin until they are no longer visible. Ointments are placed on the skin and may either rubbed in until no longer visible, or applied in a layer that is left on the skin. Always follow the practitioners order for how much ointment to apply.

Transdermal medication

A transdermal medication is a topical medication that enters the patient's bloodstream and exerts a systemic effect (Craven, 2009). Most transdermal medications are applied as patches that control the amount of medication that is released so the patient receives a constant amount of medication over a set time period. The most common medications that are administered transdermally include nitroglycerin and pain medications, such as fentanyl. Always wear gloves when applying a transdermal medication to avoid absorption of the medication into your skin. Also, remember to remove the previous transdermal medication before applying the new medication, and rotate the site of administration.

Heat increases the absorption of transdermal medication, so if the patient has a temperature greater than 102 F, check with the practitioner before administering the medication. Also, never apply transdermal medication to broken skin because it may increase the rate of absorption, or cause erratic absorption.

Ophthalmic and otic medications

Ophthalmic medications are placed into the eye to treat eye infections, irritations, or glaucoma. When administering an ophthalmic medication, make sure not to touch the tip of the dropper to the patient's eye or eyelid.

Otic medications are placed in the patient's ear and are used to treat ear infections or remove or soften cerumen. Make sure the medication is at room temperature before administering it because if it is too hot or too cold it could cause nausea, vertigo, and pain.

Inhalation administration

Drugs are administered via inhalation because it is the easiest and fastest way to get drug directly to the airways, and there is little systemic effect. The most frequent type of device you will use to administer medication to the respiratory tract is a handheld inhaler. Handheld inhalers are used to administer medications such as bronchodilators and corticosteroids to the respiratory tract. When using an inhaler to administer medication, make sure the patient exhales, and then place the inhaler about 3" in front of his mouth. Have the patient begin to inhale with his mouth open, and then depress the inhaler to administer the medication. Have the patient hold his breath for 10 seconds, or as long as possible. This helps the medication reach the bronchioles in the lungs. After the patient uses a corticosteroid inhaler, have him rinse his mouth with water to help decrease the chance of fungal infections. Also, if you are administering a bronchodilator and a corticosteroid, administer the bronchodilator about five minutes before the corticosteroid. This allows the bronchodilator to open the bronchioles, which helps the corticosteroid be as effective as possible.

Cheap antibiotics online from pharmacy

Parenteral administration

Parenteral medication administration refers to the administration of medications by injection or infusion (Food and Drug Administration, 2006).Administering medication by the parenteral route promotes a quicker onset of drug action and higher drug levels because the drug avoids the breakdown that may occur in the liver or GI tract. Methods of parenteral administration include intradermal, subcutaneous, intramuscular, and intravenous administration.

Intradermal injection

Intradermal injections are administered into the dermis layer of skin. These injections are most commonly used for allergy and tuberculin skin testing. The most common areas of administration are the inner forearm, the upper arm, and the scapula. You will usually use a 1-ml syringe with a 3/8" to 5/8" 25G syringe to administer an intradermal injection.

After injecting the medication, do not massage or apply pressure to the site. The dermis is highly vascular and will quickly absorb the medication. If you are administering multiple injections, such as with allergy testing, circle and label each site with a marking pen in order to track the response to each individual substance. If you are administering an allergen test, make sure you have epinephrine and other emergency medications on hand in case the patient experiences an anaphylactic reaction to the antigen.

Subcutaneous injection

Subcutaneous injections are administered into the subcutaneous tissue located beneath the dermis and above the layer of muscle. Subcutaneous injections allow for slow, sustained absorption of the medication. Also, subcutaneous injections cause little trauma to the tissues.

The most common types of medications that are administered subcutaneously are heparin and insulin, although some patients may have continuous subcutaneous pumps in place that administer medications such as morphine and fentanyl for pain control or terbutaline for premature labor.

Subcutaneous injections are usually given in areas with layer of subcutaneous fat, such as the abdomen, upper arm, or upper thigh. How fast the medication is absorbed depends on the area that it's injected into: the abdomen has the fastest rate absorption while the upper thigh and buttocks have significantly slower rates of absorption. When giving a subcutaneous injection, avoid areas that are reddened, scarred, edematous, or have a wound or a lesion.

Subcutaneous injections are administered with a short, small gauge needle. The volume of medication administered subcutaneously is 0.5 to 1.0 ml. When you administer the medication, pinch " to 1" of skin, and insert the needle at a 45-degree angle. Pull the plunger back to check for blood; if you get a blood return, the needle is a vein and you need to withdraw the syringe, discard it in the appropriate container, and begin the process again. If you don't get a blood return, slowly inject the medication. After you inject the medication, withdraw the syringe at the same angle that you inserted it. For medications other than heparin and insulin, gently massage the site after you withdraw the needle to help increase absorption.

When giving regular subcutaneous injections, make sure you rotate the site of administration. This helps prevent the formation of lipodystrophy, or lumps that can form in the skin after repeated injections. Also, always double check the dose of heparin and insulin before you administer it to help prevent medication errors.

Intramuscular injection

Intramuscular injections are given into the muscle layer that is located below the dermis and subcutaneous tissue. The muscle tissue has a rich blood supply that allows the medication to move quickly into the bloodstream. Other advantages of intramuscular injection include:
  • the medication isn't subjected to breakdown by digestive enzymes
  • little pain due to the few sensory nerves in the muscle tissue
  • the ability to deliver up to 5 ml of medication in a single injection (Craven, 2009).

Medications that are administered intramuscularly include antibiotics, pain medication, and immunizations. There are four sites that are used to administered intramuscular injections: the deltoid; the ventrogluteal; the vastus lateralis; and the dorsogluteal.

The decision of which muscle to use for the injection is based on factors that include the patient's age, the medication being administered, the volume of medication being administered, and the general health of the patient.

Although the location you may administer an intramuscular injection may vary, the technique that you use will be the same each time. You want to encourage the patient to relax; if he is tense, he will feel more pain in the muscle when you insert the needle. If the patient is tense or complains of pain from multiple injections, numb the area with a small amount of ice for no more than 30 seconds before you administer the injection. Always insert the needle at a 90-degree angle with a quick, dart-like motion. After you insert the needle, pull back on the syringe to make sure that no blood is seen and you aren't in a blood vessel. After administering the medication, quickly remove the needle and place gentle pressure on the site.


The deltoid muscle has a small muscle mass under a thin layer of subcutaneous fat. The typical volume of medication administered into this site is 0.5 to 2.0 ml. Medication injected into this site is rapidly absorbed, but the muscle is rarely used for injections because it's proximity to both the radial and brachial nerves.

To locate the appropriate deltoid site to administer an injection, draw an imaginary line approximately two fingerbreadths below the lower edge of the acromion process. The injection is given along this line, over the midaxillary line. When you insert the needle, angle it slightly toward the acromion process to help minimize the risk of hitting either of the nerves in the area.


The ventrogluteal site, located on the lateral aspect of the hip, is a preferred site for administering intramuscular injections. It is free of major blood vessels and nerves, and has a small amount of subcutaneous fat. It is considered the least painful of all the sites to administer an intramuscular injection. The typical volume of medication administered into this site is 1.0 to 4.0 ml.

To locate the appropriate ventrogluteal site to administer an injection, first locate and place the heel of your hand on the greater trochanter of the femur.Angle your index finger toward the anterior superior iliac spine, and your middle finger toward the iliac crest. The injection should be administered into the triangular area formed by your hand and fingers, with the needle angled slightly toward the iliac crest. However, to reduce the risk of accidental needlestick, remove your hand before you administer the injection.

Vastus lateralis

The vastus lateralis is a large muscle in the thigh that offers rapid absorption of medication. It also has no large blood vessels or nerves, making it safe to use in most patients. The typical volume of medication administered into this site is 1.0 to 4.0 ml. This is the muscle that is most commonly used to administer an intramuscular injection to children under the age of 3 years.

To locate the appropriate vastus lateralis injection site, find the area a handbreadth below the greater trochanter and a handbreadth above the knee.Then, insert the needle into the medial outer portion of the thigh in this area. Before you administer the injection, bunch the muscle in your hand, which helps pull the muscle away from the bone.


The dorsogluteal site, located on the buttocks, was a popular choice for intramuscular injection administration in the past. However, it is close to the sciatic nerve and the superior gluteal artery, and has a thick layer of subcutaneous fat; these factors have decreased the use of the muscle for injection administration. The typical volume of medication administered into this site is 1.0 to 5.0 ml.

When preparing to administer an intramuscular injection the dorsogluteal muscle, it is very important to correctly locate the muscle. Position the patient in the prone position with his toes pointed inward may help decrease pain and bleeding that may occur in the muscle. To find the correct location to administer the injection, use your index fingers to draw an imaginary line between the posterior superior iliac crest and the greater trochanter. Give the injection above and to the outside of this line, with the needle at a 90-degree angle.

Z-track injection

If you are administering a medication that may be irritating to the subcutaneous tissue or that may discolor the subcutaneous tissue, you should use the Z-track injection technique. This technique displaces the skin and subcutaneous tissue over the muscle where you inject the medication, so the medication can't leak back up the tract of the needle and irritate the subcutaneous tissue. To give a Z-track injection, place your fingers on the surface of the skin over the injection site. Gently displace the skin about ", and then insert the needle at a 90-degree angle at the site where your finger was originally. After injecting the medication, remove the needle at a 90-degree angle, and then remove your finger and allow the skin to return to position. Never massage the area where you give a Z-track injection, because this could move the drug into the subcutaneous tissue.

Intravenous administration

Intravenous medication administration has many advantages over other forms of medication administration. These advantages include:
  • rapid onset of action
  • predictable blood levels
  • can be used when the patient has gastrointestinal dysfunction
  • larger doses of medication that can be administered.
Intravenous medication administration also has disadvantages, which include a higher cost than other routes of administration, the difficulty involved in the administration, and increased complications (Craven, 2009).

Intravenous medications can be administered by I.V. push, intermittent infusion, or continuous infusion.

I.V. push

I.V. push is used to administered medications directly through the I.V. catheter in less than one minute. This allows for rapid therapeutic effect, such as needed in emergency situations. An I.V. push may be administered into either a continuous I.V. infusion, or a saline-locked I.V. catheter. Always check the rate of administration, either by checking a drug reference book, or by asking the pharmacist. Some medications can not be given by I.V. push because of the risk of serious complications. One example is potassium chloride. If potassium chloride is administered I.V. push, it can cause severe cardiac arrhythmias, and possibly death.

Before administering a medication via I.V. push into a saline-locked catheter, flush the catheter with saline solution to make sure it is still patent (Infusion Nurse's Society, 2006). If the patient complains of burning or pain, or if you see swelling, remove the catheter and restart another catheter in a new site before administering the medication. During and after I.V. push administration, always monitor the patient carefully. Adverse effects may occur very quickly, and you need to be aware and ready to treat the patient.

Intermittent infusion

Intermittent infusion is the most common method of administering I.V. medications. Intermittent infusion is used to administer medications over 20 to 60 minutes. These medications come from the pharmacy is a bag or syringe that is labeled with the patients name and medical record number, name of the medication type of I.V. fluid or diluent, and the rate of administration.

Because of the risk of serious medication errors with I.V. medications, always check the following when administering I.V. medications:
  • the medication supplied matches the medication ordered
  • the medication is appropriate for the patient to receive
  • the I.V. catheter is patent
  • the rate of administration is correct for the patient and the medication.

If you are hanging an intermittent infusion into a continuous I.V. infusion, you can do it either with by stopping the continuous fluid or keeping the continuous fluid running. If you opt to stop the continuous fluid, called a piggyback infusion, you need to hang the intermittent infusion medication higher than the continuous medication. Gravity will infuse the intermittent medication first, and then when it is done, the continuous infusion will begin. If you want to keep the continuous fluid running, hang both containers at the same level, and they will both infuse at the rate that you set.

Continuous infusion A continuous I.V. infusion is used to infuse medications that are given continuously to keep blood levels steady or that can be dangerous if given over a short period of time. Continuous I.V. infusions are given in amounts ranging from 250 to 1000 ml of fluid.

An I.V. pump should be used any time a continuous I.V. medication is given (Joint Commission, 2009). This helps decrease the risk of the administration rate changing, which could cause serious complications for the patient. Even though an I.V. pump is used to administer the medication, you need to check the medication and the I.V. site at least every 2 hours to make sure there are no problems. If the patient is receiving a high-risk medication, such as chemotherapy or potassium-chloride, you should check it more frequently. Always be familiar with the medication you are administering, including why the patient is receiving the medication, the rate of administration, and adverse effects (Infusion Nurses Society, 2006).


Aschenbrenner, D., and Venable, S. (2009). Drug Therapy in Nursing (3rd ed.). Philadelphia: Lippincott Williams & Wilkins.

Craven, R.F., and Hirnle, C.J. (2009). Fundamentals of Nursing: Human Health and Function (6th ed.). Philadelphia: Lippincott Williams & Wilkins.

Food and Drug Administration. Route of drug administration. Retrieved March 2009, from

Infusion Nurses Society (2006). Infusion Nursing Standards of Practice. Journal of Infusion Nursing 29(1 Suppl):S1-92.

Institute of Medicine (IOM), Committee on Quality of Health Care in America. (1999). To err is human: Building a safer health system. Washington, D.C.: National Academy Press.

The Joint Commission (2009). National Patient Safety Goals. Retrieved March 2009, from

Rozich, J.D., et al. (2003). Adverse drug event trigger tool: a practical methodology for measuring medication related harm. Quality and Safety in Health Care 12(3):194-200.
Question No.5.What is the safest route of medication administration?

a.Oral route
b.Intravenous route
c.Intramuscular route
d.Subcutaneous route

Question No.6.You are preparing to administer an oral medication to a patient who has trouble swallowing pills. What should you use to help him swallow the pill?

a.Orange juice
c.Chicken broth

Question No.7.What action is contraindicated when administering heparin subcutaneously?

a.Aspirate for blood
b.Massage the site
c.Pinch the skin
d.Document the injection

Question No.8.What intramuscular injection site is most commonly used for children younger than age 3?

c.Vastus lateralis
d.Ventral gluteal

Question No.9.What is one benefit of intravenous medication administration compared to oral medication administration?

a.Decreased cost
b.Ease of administration
c.Fewer complications
d.Rapid onset of action

Question No.10.How often should you check a continuous intravenous infusion?

a.At least every 2 hours
b.At least every 4 hours
c.At least every shift
d.At least daily
Medication Administration > Chapter 2
Page Last Modified On: March 12, 2016, 01:57 PM