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Chapter 1
Drugs/Agents and
Factors Affecting Their
Action
Pharmacology



Study of the history, sources, and
physical and chemical properties of
drugs
Also looks at the ways in which drugs
affect living systems
Various subdivisions of pharmacology
have evolved
1-2
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Pharmacodynamics


Study of the biochemical and
physiological effects of drugs
Study of drugs’ mechanisms of action
1-3
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Pharmacokinetics
Study of the absorption, distribution,
biotransformation (metabolism), and
excretion of drugs
Four steps






Absorption
Distribution
Metabolism
Excretion
1-4
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Pharmacotherapeutics


Study of how drugs may best be used in
the treatment of illnesses
Study of which drug would be most
appropriate or least appropriate to use
for a specific disease; what dose would
be required; etc.
1-5
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Pharmacognosy


The study of drugs derived from herbal
and other natural (plant and animal) drug
sources
Studying compositions of natural
substances helps to gain knowledge for
developing synthetic versions
1-6
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Toxicology


Study of poisons and poisonings
All drugs have the potential to become
toxic.
1-7
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History of Pharmacology

Ancient Egypt: the cradle of
pharmacology


These medical sources listed over 700
different remedies for different ailments.
First century: Dioscorides prepared De
Materia Medica:

Listed and classified 600 different plants
used for medicinal purposes; first time plants
were ever classified
1-8
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Sources of Drugs

Drugs derived from:



Natural sources
Semisynthetic sources
Synthetic sources
1-9
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Drug Uses






Symptomatic treatment
Prevention
Diagnostic drugs
Curative
Health maintenance
Contraception
1 - 10
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Dosage Forms






1 - 11
Tablets
Timed or sustained release
Tablets or controlled release
Capsule
Troches
Suppositories
(continues)
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(continued)
Dosage Forms





Solutions
Douche
Suspensions
Emulsions
Topicals


Patches
Drug implants
1 - 12
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Parenteral Product Packaging

Ampules




Sterile
Sealed glass or plastic container
Contain a single liquid dose
Vials: either single or multiple dose



Glass or plastic container
Sterile liquid dose
Sealed with a rubber diaphragm
1 - 13
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Drug Names

Chemical name


The drug’s chemical composition and
molecular structure
Generic name (nonproprietary name)


Name given by the United States Adopted
Names Council
Allows the drug to be marketed
1 - 14
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Brand Name

Also called trade name (proprietary
name)



The drug has a registered trademark; use
of the name is restricted by the drug’s owner
(usually the manufacturer)
Allows the drug to be commercially
distributed
The superscript ® is registered by the U.S.
Patent Office and approved by the FDA
(Food and Drug Administration)
1 - 15
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Drug Names: Examples

Chemical name


Generic name


(+/-)-2-(p-isobutylphenyl) propionic acid
Ibuprofen
Trade name

Motrin
1 - 16
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U.S. Drug Legislation

Pure Food and Drug Act of 1906


Federal Food, Drug, and Cosmetic Act of
1938

1 - 17
Required all drugs to meet minimal
standards
Required the drug to be safe before being
distributed over state lines
(continues)
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(continued)
U.S. Drug Legislation

1970: Comprehensive Drug Abuse
Prevention and Control Act


Also known as Controlled Substance Act:
classified drugs according to their abuse
potential
Regulates the manufacture and distribution
of drugs causing dependence
1 - 18
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Controlled Substances Schedules
Schedule I
High potential for
abuse
No medical use
Heroin
LSD
Schedule II
High potential for
abuse
Accepted medical
use
Morphine
Demerol
Schedule III
Lower potential for
abuse
Accepted medical
use
Librium, Valium,
hydrocodone,
Tylenol with codeine
Schedule IV
Lower potential for
abuse
Accepted medical
use
Librium
Valium
Schedule V
Lowest potential for
abuse
Accepted medical
use
Lomotil
Robitussin A-C
1 - 19
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Prescription Drugs


Prescription drugs = legend drugs
Drugs prescribed by:






Physician
Nurse practitioner
Physician’s assistant
Dentist
Veterinarian
Others
1 - 20
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Principles of Drug Action

Drugs


Alter existing cellular or chemical functions
Exert their action by forming a chemical
bond with specific receptors within the body

1 - 21
Referred to as a lock and key effect
(continues)
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(continued)
Drug receptor interaction. Binding with specific receptors
occurs only when the drug and its receptors have a
compatible chemical shape.
1 - 22
(continues)
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(continued)
Principles of Drug Action
Receptors



1 - 23
The better the fit, the stronger the drug’s
affinity, thus
Drug effect occurs at lower doses
(continues)
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(continued)
Principles of Drug Action




Agonist effect
Antagonistic effect
Adverse drug effect
Therapeutic effect
1 - 24
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Pharmacokinetics: Absorption
Routes




Oral
Parenteral
Topical
1 - 25
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Metabolism: First-Pass Effect

The metabolism of a drug and its
passage from the liver into the circulation

Metabolism occurs in the liver



Liver enzymes react with the drug
Increases the dosage requirement
The same drug—given IV—bypasses the
liver, preventing the first-pass effect from
taking place, and more drug reaches the
circulation.
1 - 26
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Pharmacokinetics: Distribution

The transport of a drug in the body by
the bloodstream to its site of action
1 - 27
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Elimination/Excretion
The elimination of drugs from the body




1 - 28
Kidneys (main organ)
Liver
Bowel
(continues)
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(continued)
Renal excretion of drugs. Note sites where
drugs are secreted and reabsorbed.
1 - 29
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Pharmacokinetics:
Measuring Drug Action
Half-life


The time it takes for one half of the original
amount of a drug to be removed from the body
1 - 30
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Chapter 2
Principles and Methods
of Drug Administration
Nursing Process





Assessment
Nursing diagnosis
Planning
Implementation
Evaluation
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Administering Medication





Assessment
Nursing diagnosis
Planning
Implementation
Evaluation
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The Five (or Seven) Rights
of Medications
1.
2.
3.
4.
5.
6.
7.
Right drug
Right dose
Right client
Right time
Right route
Right documentation
Client’s right to refuse
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Parenteral Medications




Intramuscular administration
Subcutaneous administration
Intradermal administration
Intravenous administration
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Additional Methods of
Administration




Vaginal
Rectal
Ear
Eye




Nasal
Nasogastric
Epidural
Transdermal patches
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Chapter 3
Nursing Clients Receiving
Drugs Intravenously
Intravenous Administration

Collect materials needed.





Select IV tubing.
Select IV needle.
Explain the procedure.
Prepare the site.
Secure the site.
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Complications







Infiltration
Extravasation
Thrombophlebitis
Pain
Fluid overload
Pyrogenic reactions
Tissue necrosis
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Calculations

Total number of milliliters to be infused = Time in hours
mL/hr

mL/hr
= mL/min
time in minutes

mL/min x SDF = gtt/min
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IV Administration at Home


Home care/client teaching
Home health nurses






Provide written guidelines
Teach IV complications
Teach when to call the nurse
Teach dressing change guidelines
Teach how to heparinize and flush a
catheter
Have the client return demonstrate skills
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Chapter 5
Drug Therapy for
Pediatric Clients
Pediatric Drug Therapy


Approximately 75% of all prescription
drugs in the U.S. lack full approval by the
FDA because most drugs are not studied
on children.
Studying the effects of drugs in children
is a problem.
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Absorption




Gastric acid (hydrochloric acid)
secretion in infants
Choosing the intramuscular injection
site
Topical drug absorption
Intravenous drug administration
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Distribution

Dependent upon the amount of water
and/or fat present in the child, as well
as plasma affinity of the drug and
protein-binding activity


Water-soluble drugs effectively utilized
Protein binding capacity is less
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Metabolism


Difficult to predict
Maternal drug history is important
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Excretion

Kidney maturation


Excretion increases as the kidney matures
Drug toxicity decreases as the kidney
matures
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Pediatric Drug Sensitivity

Central nervous system drugs

Barbiturates and morphine


Depressant effects are exaggerated
Lowering body temperature

Acetaminophen
•

Becomes toxic easily with large doses
Salicylates
•
Do not give to children under the age of 12.
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Pediatric Dosages

Determined by using a nomogram

Nomograms are generally accurate after
the attainment of mature liver and kidney
function.
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Rights to Follow


Allow adequate time for drug
administration.
Gain the child’s trust.



Never lie to the child.
Consider the child’s developmental
level.
Prevent choking.
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Administration Methods

Liquid medications are administered
using an infant dropper, syringe without
a needle, or a small spoon
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Parenteral Medications


Explain the procedure to the child and to
the parents.
Use additional materials such as:





Booklets
Coloring books
Puppets
Dolls
IV setup with colored water
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Painful Procedures





Allow the parents to stay.
Painful procedures should be done in a
separate room designated as the “owie”
room.
Use a firm positive manner.
Assemble equipment first.
Maintain the child’s safety.
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Intramuscular Injections


Vastus lateralis is the preferred site for
children under the age of 3.
Ventrogluteal site is the preferred site
for children over the age of 3.

The child should be walking.
(continues)
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(continued)
Anterior view of the location of the vastus
lateralis muscle in a young child.
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Final Step in Administering Drugs


Evaluate drug action
Remember



Children are vulnerable.
Be kind and patient.
Enjoy the children; you will receive more
than you give.
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Chapter 28
Anxiolytics and Other
Agents Used to Treat
Psychiatric Conditions
Psychotherapeutics


Treatment of emotional and mental
disorders
Commonly prescribed drugs

Used when a person’s ability to cope with
his or her environment is seriously impaired
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Treatment

Drug agents used for treatment of:




Anxiety
Mental and emotional disorders
Psychoses
Psychosis and affective disorders
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Anxiolytic Groups

Four groups of anxiolytics (antianxiety)
drugs used in the U.S.




Barbiturates
Carbamates
Antihistamines
Benzodiazepines
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Affective Disorders

Two classes of agents used to treat
affective disorders


Antidepressant agents
Antimanic agents
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Anxiolytics

Barbiturates

The oldest drugs to be used as anxiolytic
agents



Depress the CNS
Suppress REM sleep
Carbamates


Depress the CNS
Similar to barbiturates
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Antihistamines and
Benzodiazepines

Antihistamines



Used as anxiolytics
Cause sedation
Benzodiazepines


First line of drugs used for anxiety disorders
Produce sedation and muscle relaxation
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Anxiolytics: Side Effect/Adverse
Effects

Usually safe


Sedation
Relaxation


Check vital signs
Dangerous when taken with:


Other sedating medications
Alcohol


Respiratory arrest
Check kidney and liver labs
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Antipsychotic Agents

Treat mood disorders



Schizophrenia
Organic psychoses
Manic phase of bipolar affective disorders
(continues)
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(continued)
Antipsychotic Agents


Clients with psychotic disorders show
symptomatic improvement
Action

Inhibit or alter the dopamine-mediated
response in the brain
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Side Effects/Adverse Effects

Extrapyramidal symptoms






Tardive dyskinesia
Impaired temperature regulation
Lower the seizure threshold
Endocrine changes
Dermatological changes
Photosensitivity
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Clozapine (Clozaril)

An example of an antipsychotic drug
agent


Very effective
Produces fewer side effects and adverse
effects

Agranulocytosis
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Antidepressant Agents

Cyclic antidepressants

Tricyclics

Work by correcting an imbalance in the
norepinephrine transmitter
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Tricyclic Antidepressants

Used to treat




Depression
Chronic pain
Bedwetting
Examples: amitriptyline and imipramine
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Cyclic Antidepressants

Adverse/side effects

Orthostatic hypotension, extrapyramidal
effects, sedation, weight gain, dry mouth,
tachycardia, urinary retention, tremors,
sexual dysfunction
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Monoamine Oxidase Inhibitors
(MAOIs)

Inhibit monoamine oxidase

Monoamine oxidase


Normally inactivates neurotransmitters such as
serotonin and dopamine
Dangerous side effects



Hypotension
Hypertension
Death
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Newer Agents

Sertraline HCl (Zoloft), Fluoxetine HCl
(Prozac), Paroxetine HCl (Paxil)

Action: act in a similar fashion to the tricyclic
antidepressants


Produce fewer sedative and anticholinergic
effects
Adverse effects and side effects
•
Nausea, dry mouth, headache, and dizziness
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Pediatric Considerations


Higher risk for side effects, especially
extrapyramidal symptoms
Lithium, an antimanic agent, may lead to:



Decreased bone density
Decreased bone formation
Children are very sensitive to these
agents.
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Geriatric Considerations

The elderly process these agents much
slower


Side effects


Toxic effects
Orthostatic hypotension, sedation, and
anticholinergic side effects
Increased anxiety is associated with the
use of tricyclic antidepressants
(continues)
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(continued)
Geriatric Considerations


May experience higher incidence of
cardiac dysfunction such as a myocardial
infarction
Lithium is more toxic in elderly clients;
lower doses are necessary.
Copyright 2007 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved.
Chapter 38
Agents Used in
Obstetrical Care
Agents Used in Obstetrical Care

This presentation focuses on the
following drug agents:




Uterine stimulants
Uterine relaxants
Lactation suppressants
Abortion inducers
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Oxytocin


Stimulates the uterus and the mammary
glands
Affects the smooth muscle of the uterus
to promote childbirth


Increases frequency and force of uterine
contractions
Forces milk into mammary sinuses for
the to infant
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Uterine Relaxants


Prevent premature labor
Ritodrine HCl

A beta-adrenergic stimulant


Relaxes the uterus
Terbutaline sulfate (Brethine)

Stimulates beta2 receptors

Relaxes the uterus
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Lactation Suppressants

Bromocriptine mesylate (Parlodel)


A nonhormonal ergot derivative
Estrogen is no longer used.

High risk for thromboemboli and cancer of
the reproductive tract
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Abortion Inducers

First trimester


Suction curettage
Second trimester



Intra-amniotic injection of hypertonic (20%)
NaCl
Oxytocin
Prostaglandins

Most useful
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