NCLEX-RN: Pharmacology

Pharmacology: Dosage and Preparation Forms

Focus topic: Pharmacology

Pharmacology: Solids

Focus topic: Pharmacology


A. Extract—obtained by dissolving drug in water or alcohol and allowing solution to evaporate; residue is the extract.
B. Powder—finely ground drugs.
C. Pill—common term for tablet; made by rolling drug and binder into a sphere.
D. Suppository.

  • Contains drugs mixed with a firm base.
  • Liquefies at body temperature when inserted into orifice.
  • Releases drug to produce a local or systemic effect.

E. Ointment—semisolid mixture of drugs with a fatty base.
F. Lozenge—flavored flat tablet that releases drug slowly when held in mouth.
G. Medication patch.

  • Premeasured medication paper (also called transdermal medication).
  • Check manufacturer’s directions for

H. Capsule.

  • Drugs in small, cylindrical gelatin containers that disguise the taste of the drug.
  • Capsule can be opened and drug mixed with food or jam to mask taste.

I. Tablets.

  • Dried, powdered drugs that are compressed into
    a small disk, which easily disintegrates in water.
  • Enteric coated—tablet does not dissolve until reaching intestines, where release of drug occurs.

Pharmacology: Liquids

Focus topic: Pharmacology

A. Fluid extract.

  • Concentrated fluid preparation of drugs produced by dissolving crude plant drug in a solvent.
  • Strength of extract is such that 1 mL (about ¼ teaspoon or 15 to 16 gtt) represents 1 g of the drug at 100% strength.

B. Tincture.

  • Diluted alcoholic extract of a drug.
  • Varies in strength from 10% to 20%.

C. Spirit—preparation of volatile (easily vaporized) substances dissolved in alcohol.
D. Syrup—drug contained in a concentrated sugar solution.
E. Elixir—solution of drug made with alcohol, sugar, and some aromatic or pleasant-smelling substance.
F. Suspension.

  • Undissolved, finely divided particles of drug dispersed in a liquid.
  • Shake all bottles of suspension well before giving.

G. Emulsion—suspension of unmixed oils, fats, or petrolatum in water.
H. Liniment and lotion—liquid suspension of medication applied to the skin.

Pharmacology: Packaging Methods and Dispensing

Focus topic: Pharmacology

A. Unit dosage package method.

  • Package contains pre-measured amount of drug in proper form for administering.
  • Procedures for delivery and storage vary from hospital to hospital.
  • Nurse administers the medication to the client.

B. Traditional method.

  • Nurse prepares medication on the unit.
  • Supplies come from stock or bulk on the ward or from client’s multiple-dose bottle.

C. The nurse is responsible for accuracy of the medication given, regardless of the packaging or dispensing method used.

Pharmacology: Routes of Administration

Focus topic: Pharmacology

Pharmacology: Oral Route

Focus topic: Pharmacology

A. Ingested (swallowed).
B. Sublingual (under tongue).
C. Buccal (on mucous membrane of cheek or tongue).

Pharmacology: Rectal Route

Focus topic: Pharmacology

A. Suppository.
B. Liquid (retention enema).

Pharmacology: Parenteral Route

Focus topic: Pharmacology

A. Intravenous.

  • The response is fast and immediate.
  • More than 5 mL medication can be given.
  • Drug must be given slowly and usually in diluted form.
  • Check medication leaflets to determine if medication route is IM or IV. Some drugs but not all are prepared to be given either IM or IV.

B. Intradermal.

  • Injected below the surface of the skin; usual site is inner aspect of forearm or scapular area of back.
  • A short bevel 25–27 gauge, ⅜–½-inch needle is used.
  • Needle must be inserted with bevel up.
  • This route is usually used to inject antigens for skin or tuberculin tests. It is sometimes used to check for medication allergy as the dermis has limited blood supply so absorption of drug injected is reduced and occurs very slowly. This method is not used for administration of medications.
  • Amount injected ranges from 0.01 to 0.1 mL.

C. Subcutaneous.

  • A 25–29 gauge, ⅜–⅝-inch needle is used.
  • Injection site is the fatty layer under skin.
    a. Abdomen—stay at least 2 inches away from the navel and/or any scars.
    b. Lateral upper arm or thigh.
  • This route usually used for injecting medication that is to be absorbed slowly with a sustained effect.
  • Amount injected ranges from 0.5 to 2 mL.
  • Rotation of sites no longer necessary because newer human insulins have lower risk for hypertrophy.
  • Several new technologies are available for administration of subcutaneous injections.
    a. Injection pens—clients can use to selfadminister medications (e.g., Epipen [epinephrine], insulin, interferon) subcutaneously.
    b. Needleless injection systems—use high pressure to penetrate the skin with the medication into the subcutaneous tissue.

D. Continuous subcutaneous infusion (CSQI or CSCI).

  • Fewer risks and less expense than IV administration, easy to operate.
  • Used for selected medications (e.g., opioids, insulin).
  • Improves oncologic and postoperative pain control in infants, children, and adults.
  • Use the needle with the shortest length and the smallest gauge necessary to establish and maintain the infusion.
  • Site selection depends on a client’s activity level and the type of medication delivered. Avoid sites where the tubing of the pump could be disturbed.
  • Rotate sites used for medication administration at least every 2 to 7 days, or whenever complications such as leaking occur.
  • The CSQI route requires a computerized pump with safety features, including lockout intervals and warning alarms.
  • After initiating CSQI, immediately document medication administration details per policy in client’s medical record.
  • Report adverse effects from medication or infection at insertion site according to agency policy.
  • Teaching.
    a. Follow client teaching instructions that come with each pump.
    b. Instruct client to wear medical alert bracelet along with medical information, including disease (e.g., diabetes), allergies, and a contact phone number for the pump manufacturer.
  • Pediatric.
    a. CSQI used with insulin improves glycemic control in children and adolescents and offers greater flexibility for adolescents, placing the responsibility of diabetes management on the child.
    b. Extensive child and family education is needed in using CSQI.
  • Gerontologic
    a. CSQI delivers isotonic IV solutions to dehydrated older adults, known as hypodermoclysis therapy.
    (1) Easy to use.
    (2) Safe.
    (3) Cost-effective alternative to IV hydration for older adults.
    b. Avoids the need to transfer a client from home or a long-term care facility to an acute care hospital.
    c. Infuse fluids slowly (e.g., 30 mL/hr) during the first hour of therapy.
    (1) If the client remains comfortable, increase the rate of infusion.
    (2) Infusion rates do not exceed 60 mL/hr.
  • Home care
    a. Clients need a responsible family caregiver.
    b. Educate the client, family, and/or significant others about:
    (1) The desired effect of the medication.
    (2) Side effects and adverse effects of the medication.
    (3) Operation of the pump.
    (4) How to evaluate the effectiveness of the medication.
    (5) When and how to assess and rotate injection sites.
    (6) When to call a healthcare provider about problems.
    (7) Where and how to obtain and dispose of all required supplies.
    c. Clients managing CSQI at home may use an antibacterial soap (e.g., Hibiclens, pHisoHex) instead of alcohol and chlorhexidine to clean the insertion site.

E. Intramuscular

  • Needle gauge and length will vary with site.
    a. Deltoid—located by having client raise arm.
    (1) A 23- to 25-gauge, ⅝- to 1-inch needle is used.
    (2) Administer no more than 2 mL.
    b. Thigh.
    (1) Needle must be long enough to reach muscle; may vary from 2 to 8 cm.
    (2) Needle gauge depends upon substance of medication.
    (3) Oil bases require 20 gauge; water bases require 22 gauge.
  • Absorption rate of IM medication dependent on circulation of person injected.
  • This route usually used for systemic effect of an irritating drug.
  • Amount of medication must not be over 5 mL, as absorption would be prolonged, difficult, and painful. It is best to limit to 3 mL.
  • Techniques for lessening pain for the client using an IM medication.
    a. Reduce puncture pain by “darting” needle.
    b. Prevent antiseptic from clinging to needle during insertion by waiting until skin antiseptic is dry.
    c. If medication must be drawn through a rubber stopper, use a new needle for injection.
    d. Avoid sensitive or hardened body areas.
    e. After needle is under skin, aspirate to be certain that needle is not in a blood vessel.
    f. Inject slowly.
    g. Maintain grasp of syringe.
    h. Withdraw needle quickly after injection.
    i. Apply gentle pressure. Do not massage site as this will damage underlying tissue.
  • Z-track method of IM injection is the preferred method for administering IM injections because it prevents leakage, or tracking, of medication into the subcutaneous tissue. Displacement of the skin during the injection helps to seal the drug in the muscle. Other than lateral displacement of the skin, procedure for administration is same as for any IM injection including aspiration before injection, maximum amount to be injected.
  • Observe for side effects of medication following injection.

Pharmacology: Other Routes

Focus topic: Pharmacology

A. Inhalation route.
B. Topical route.



Pharmacology: Medication Administration

Focus topic: Pharmacology

Pharmacology: Basic Guidelines for Medication Administration

Focus topic: Pharmacology

A. Determine the correct dosage, actions, side effects, and contraindications of any medication before administration.

B. Determine if medications ordered by the physician are appropriate for client’s condition. This is part of the nurse’s professional responsibility.

C. Question the physician about any medication orders that are incomplete, illegible, or inappropriate for the client’s condition.

  • Remember, the nurse may be liable if a medication error is made.
  • Report every medication error to the physician and nursing administrator.
  • Complete a medication incident report.

D. Check to determine if the medication ordered is compatible with the client’s condition and with other medications prescribed.
E. Ascertain what the client has been eating or drinking before administering a medication.

  • Determine what effect the client’s diet has on the medication.
  • Do not administer medication if contraindicated by diet. For example, do not give a monoamine oxidase (MAO) inhibitor to a client who has just ingested cheddar cheese or wine.

F. Check that calculated drug dosage is accurate for the client, paying particular attention to young children, elderly people, or for very thin or obese clients. These age and weight groups require smaller or larger dosages.


Pharmacology: Documentation of Medications

Focus topic: Pharmacology

Pharmacology: Medication Orders

Focus topic: Pharmacology

A. Medication administered to client must have a physician’s order or prescription before it can be legally administered.
B. Physician’s order is a verbal or written order, recorded in a book, file, or client’s chart or electronic medication/medical record.

C. If order is given verbally over the telephone, nurse must write a verbal order in client’s chart for the physician to sign at a later date per hospital policy.
D. Written orders are safer—they leave less room for potential misunderstanding or error.
E. Drug order should consist of seven parts.

  • Name of the client.
  • Date the drug was ordered.
  • Name of the drug.
  • Dosage.
  • Route of administration and any special rules of administration.
  • Time and frequency the drug should be given.
  • Signature of the individual who ordered the drug.

Pharmacology: Types of Medication Schedules

Focus topic: Pharmacology

A. Routine orders.

  • Administered according to instructions until it is canceled by another order.
  • Can also be used for prn drugs.
    a. Administered when client needs the medication.
    b. Not given on a routine time schedule.
  • Continued validity of any routine order should be assessed—physicians occasionally forget to cancel an order when it is no longer appropriate for client’s condition.

B. One-time orders.

  • Administered as stated, only one time.
  • Given at a specified time or “stat,” which means immediately.

Legal Implications of Medication Errors

A. Nurse who prepares a medication must also give it to the client and chart it.

  • If client refuses drug, chart that medication was refused—report this information to the physician per hospital policy.
  • When charting medications, use the correct and approved abbreviations and symbols.

B. If error in a drug order is found, it is the nurse’s responsibility to question the order.

  • If order cannot be understood or read, verify with the physician.
  • Do not guess at the order as this constitutes gross negligence.
  • In many hospitals it is the pharmacist’s responsibility to contact physicians when medication orders are unclear.
  • Even when drug dose is prepared by pharmacy, it is the nurse’s responsibility to know correct drug and dose.

C. Always report medication errors to the physician immediately.

  • This action minimizes potential danger to the client.
  • Measures can be taken immediately to assess and evaluate the client’s status.
  • A plan of action can be implemented to reverse the effects of the medication.

D. Errors in medication are documented in an unusual occurrence or incident report and on the client’s record.

  • This action is necessary for both legal reasons and nursing audits.
  • Nursing audits are conducted to determine problems in medication administration.
    a. A particular source of problems.
    b. A range of problems that seem to have no connection.




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