PowerPoint® to accompany
Medical Assisting
Chapter 50
Second Edition
Ramutkowski  Booth  Pugh  Thompson  Whicker
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
1
Principles of Pharmacology
Objectives:
50-1 Describe the five categories of pharmacology.
50-2 Differentiate between chemical, generic, and trade
names for drugs.
50-3 Describe the major drug categories.
50-4 List the main sources of drug information.
50-5 Contrast over-the-counter and prescription drugs.
50-6 Compare the five schedules of controlled
substances.
2
Principles of Pharmacology
Objectives:
50-7 Describe how to register a physician with the
Drug Enforcement Administration (DEA) for
permission to administer, dispense, and prescribe
controlled drugs.
50-8 Describe how vaccines work in the immune
system.
50-9 Identify patient education topics related to the use
of nonprescription and prescription drugs.
3
Introduction
 Pharmacology –

Science of drugs
 Medication mistakes
can injure or even
cause death of a
patient.
This chapter will
provide an overview of
the role of drugs in
ambulatory medical
facilities
You will need to have a good working knowledge of the
foundations of pharmacology.
4
Medical Assistant’s Role in
Pharmacology
 You will need to:
 Have basic knowledge of
medications
 Be attentive to ensure that
the physician is aware of
all the medications a
patient is taking.
 Ask patients about use of
alcohol, vitamins, herbal
medications, or
recreational drugs
5
Drugs and Pharmacology
 Drug - chemical
compound used to
prevent, diagnose or treat
a disease or other
abnormal condition
 Pharmacologist specialist in
pharmacology
A doctor prescribes a
drug when he gives a
patient a prescription
to be filled by a
pharmacy.
You are responsible to administer a drug by giving
it directly by injection, by mouth, or by any other
route to introduce the drug into a patient’s body.
6
Categories of Pharmacology
 Pharmacognosy – study of characteristics of
natural drugs and their sources
 Pharmacodynamics – study of what drugs do to
the body
 Pharmacokinetics – what the body does to drugs
 Pharmacotherapeutics – study of how drugs are
used to treat disease
 Toxicology – study of poisonous effects of drug
7
Sources of Drugs
 Many drugs originate
as natural products
 Plants
 Animals
 Minerals
 Bacteria or fungi
Name this source of drug
and the drug it is used to
make.
Foxglove to make digitoxin
8
Food and Drug
Administration (FDA)
 An agency of the Department of Health and Human
Services.
 Regulates the manufacture and distribution of every
drug used in the U.S.
 Requires drug manufacturers to perform clinical tests
on new drugs before the drugs are used by humans.
 Manufacturer must continue to demonstrate the
drug’s safety and efficacy.
 FDA can withdraw a drug from the market at any
time if evidence suggests that it is no longer safe or
effective.
9
Pharmacodynamics
 Study of what a drug does to the body
 Includes interaction between the drug and
target cells or tissues and the body’s
response to that interaction
10
Pharmacokinetics
 The study of what the body does to a drug
includes:
 Absorbs – converts a drug into a form the
body can use
 Metabolizes – drug molecules are
transformed into simpler products
 Distributes – transporting a drug from its
site of administration to its site of action
 Excretes –manner in which a drug is
eliminated from the body
11
Pharmacotherapeutics
Drug Names:




Generic – official name
International nonproprietary name
Chemical name
Trade name – brand or proprietary
name
You will probably use only generic or trade names.
12
Apply Your Knowledge
Which of the following is a generic drug
name?



Biocef
Keflex
Cephalexin
13
Apply Your Knowledge -Answer
Which of the following is a generic drug
name?



Biocef
Keflex
Cephalexin
14
Pharmacotherapeutics - Drug
Categories
Categorized by:
 Their action on the
body
 General
therapeutic effect
 Body system
affected
Example:
Antacid – neutralizes
stomach acids
 Tums
 Basaljel
15
Pharmacotherapeutics –
Indications and Labeling
 Indications – used to
 When a drug is used
identify purpose or
for multiple indications
reason for using a drug.
one or more may not be
in its labeling.
 FDA – approved
indications which must
 Example: Benadryl
be part of labeling
can be used for
antihistamine or
 Multiple uses of a drug
temporary sedative.
are possible.
16
Pharmacotherapeutics –
Safety and Efficacy
 Safety is how many and what kinds of
adverse effects are associated with the drug.
 An adverse reaction may require immediate
action.
 Be alert to complaints from patient after starting
new drug.
17
Pharmacotherapeutics –
Safety and Efficacy (cont.)
 When a patient complains a drug is not working, it
may be due to any of the following:







Patient does not understand how the drug works
Dosage needs to be adjusted
Therapeutic level has not been reached
Wrong drug was prescribed
Some drugs work better with one patient than another
Some forms of drugs work better
The trade name drug may work even if the generic does
not
18
Pharmacotherapeutics –
Kinds of Therapy
 Acute – improve life
threatening or serious
condition
 Empiric – give until other
tests prove another therapy
is appropriate
 Maintenance – maintain a
condition
 Palliative – reduce the
severity of a condition or
pain
 Prophylactic – prevent a
disease or condition
 Replacement – provide
chemicals missing by the
patient
 Supportive – for condition
other than primary disease
 Supplemental – avoid
deficiency
19
Apply Your Knowledge
What is Pharmacokinetics?
20
Apply Your Knowledge -Answer
What is Pharmacokinetics?
The study of what a drug does to the body.
21
Pharmacotherapeutics –
Toxicology
 Study of poisonous effect
or toxicity of drugs
 Toxic effects includes:
 Adverse effect on a fetus or
infant
 Adverse reactions reported
in clinical trials
 Adverse effect in pediatric
or elderly patients
22
Sources of Drug Information
 You must keep up-to-date
sources of drug
information
 Physicians’ Desk
Reference (PDR)
 Drug Evaluations
 United States
Pharmacopeial/National
Formulary
 American Hospital
Formulary Services
(AHFS)
23
Controlled Substances
 A drug that is categorized as potentially
dangerous and addictive
 The greater the potential the more
severe limitations on prescribing it
 Controlled by federal laws
 Comprehensive Drug Abuse Prevention
and Control Act – (Controlled
Substances Act) 1970
24
Controlled Substances Schedules
Schedule
Abuse
Example
I
High
Heroin
II
High
Codeine
III
Lower than II
Butabarbital
IV
Lower than III
V
Lower than IV
Chloral
hydrate
Antidiarrheals
25
Regulatory Function of FDA
 Drug
Manufacturing
 Nonprescription or
Over-The-Counter
(OTC) drugs
 Prescription drugs
 Controlled
substances
 Controlling
substance labeling
 Doctor registration
 DEA number
use Form 224a
 Renew every
three years
26
Controlled Substances – Drug
Security
 Store controlled drugs in a locked cabinet
or safe.
 Double lock opioids
 Doctor should keep the keys at all times
except when asking you to add or take
from the stock, only if allowed in your
state
27
Controlled Substances –
Recording Keeping
 Doctors must maintain two types of records to
dispense controlled drugs:
 Dispensing records
 Must be kept separate from patient’s regular
medical record
 Note each time a drug is given
 Inventory records
 Count the amount of each drug on hand and
compare with amount dispensed to patient
28
Controlled Substances –
Disposing of Drugs
 Dispose of outdated, noncontrolled drugs by:
 Flushing down the toilet
 Putting them in the trash
 Dispose of controlled drugs
 Obtain DEA Form – 41 (Registrants Inventory of
Drugs Surrendered)
 Have doctor sign it and call DEA about how to
dispose of the drugs
29
Writing Prescriptions
 Any drug not over-the-counter requires a
prescription
 Four basic parts:
1. Superscription
2. Inscription
3. Subscription
4. Signature
30
Writing Prescriptions (cont.)
Prescription Blank for a Single Medication
31
Writing Prescriptions (cont.)
Prescription Blank for a Multiple Medications
32
Vaccines
 Special preparations made
from microorganisms
 Administered to a person
to produce reduced
sensitivity to or increased
immunity to an infectious
disease
33
Antibody Formation
1. Antigen enters body
2. White cells produce
antibodies
3. Combine with antigens to
neutralize them
4. This arrests or prevents
reaction or disease
5. Vaccines stimulate antibody
formation and reduce
symptoms if patient is
exposed to disease
34
Patient Education About Over
The Counter (OTC) Drugs
 You need to give your
attention to all the
drugs a patient is
taking whether
prescription or OTC
 Caution patient not to
treat themselves with
OTC drugs
 Inform patient that
many OTC
medications contain
more than one active
ingredient.
 Tell the patient that
interactions can occur
when a person takes
more than one OTC at
a time or takes one
with prescription drugs
35
Patient Education About
Drugs – Prescription Drugs
 Inform patient about
special considerations
and drug safety
precautions
 Encourage:
 Complete medication list
 Complete adverse
reactions list
 Patient compliance
36
Apply Your Knowledge
Why are vaccines given to patients?
37
Apply Your Knowledge -Answer
Why are vaccines given to patients?
Vaccines are administered to a person to produce
reduced sensitivity to or increased immunity to an
infectious disease.
38
Summary
Medical Assistant
You will need to have a good working knowledge of
the foundations of pharmacology.
Your need to teach patients about specific drugs and
required safety precautions .
39
End of Chapter
40