Transcript Bledsoe_V1_ch09a

Chapter 9
General Principles of
Pharmacology
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Chapter 9, Part 1
Basic Pharmacology
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Part 1 Topics
Drug Names
Sources of Drug Products
Drug Classifications
Food & Drug Administration
Medication Administration
Properties of Drugs
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Drugs are chemicals used to
diagnose, treat, and prevent
disease.
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Pharmacology is the study of
drugs and their actions on the
body.
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Names of Drugs
Chemical
– States its chemical composition and
molecular structure
Generic
– Usually suggested by the manufacturer
Official
– As listed in the U.S. Pharmacopeia
Brand
– The trade or proprietary name
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Names of Drugs
Chemical Name
7-chloro-1, 3-dihydro-1,
methyl-5-phenyl-2h-1
Generic Name
diazepam
Official Name
diazepam, USP
Brand Name
Valium®
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Sources of Drug Information
United States Pharmacopeia (USP)
Physician’s Desk Reference (PDR)
Drug Information
Monthly Prescribing Reference
AMA Drug Evaluation
EMS field guides
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Components of a Drug Profile
Name
Classification
Mechanism of
Action
Indications
Pharmacokinetics
Side Effects
Routes of
Administration
Contraindications
Dosage
How Supplied
Special
Considerations
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Names
Most frequently include generic and
trade names
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Classification
The broad group to which a drug
belongs. Knowing classifications is
essential to understanding the
properties of drugs.
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Mechanism of Action
The way in which a drug causes its
effects; its pharmacodynamics.
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Indications
Conditions that enable the appropriate
administration of the drug (as
approved by the FDA).
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Pharmacokinetics
How the drug is absorbed, distributed,
and eliminated; typically includes onset
and duration of action.
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Side Effects/Adverse
Reactions
The drug’s untoward or undesired
effects
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Routes of Administration
How the drug is given
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Contraindications
Conditions that make it inappropriate
to give the drug.
A predictable harmful event will occur if
the drug is given in this situation.
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Dosage
The amount of the drug that should be
given
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
How Supplied
This typically includes the common
concentration of the available
preparations; many drugs come in
different concentrations.
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Legal
Knowing and obeying the laws and
regulations governing medications and
their administration is an important part
of a paramedic’s career.
These include federal, state, and
agency regulations.
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Federal
Pure Food & Drug Act of 1906
Harrison Narcotic Act of 1914
Federal Food, Drug, & Cosmetic
Act of 1938
Comprehensive Drug Abuse
Prevention & Control Act of 1970
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
State vs. Local Standards
They vary widely.
Always consult local protocols and with
medical direction for guidance in
securing and distributing controlled
substances.
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
New Drug Development
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Providing Patient Care Using
Medications (1 of 4)
Know the precautions and
contraindications for all medications
you administer.
Practice proper technique.
Know how to observe and document
drug effects.
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Providing Patient Care Using
Medications (2 of 4)
Maintain a current knowledge in
pharmacology.
Establish and maintain professional
relationships with other health care
providers.
Understand pharmacokinetics and
pharmacodynamics.
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
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Providing Patient Care Using
Medications (3 of 4)
Have current medication references
available.
Take careful drug histories including:
– Name, strength, dose of prescribed
medications
– Over-the-counter drugs
– Vitamins
– Herbal medications
– Allergies
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Providing Patient Care Using
Medications (4 of 4)
Evaluate the patient’s compliance,
dosage, and adverse reactions.
Consult with medical direction as
needed.
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
The 6 Rights of Medication
Administration
Right medication
Right dosage
Right time
Right route
Right patient
Right documentation
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Special Considerations
Pregnant patients
Pediatric patients
Geriatric patients
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
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Pregnant Patients
Ask the patient if there is a possibility
that she could be pregnant.
Some drugs may have an adverse
effect on the fetus of a pregnant
female.
Teratogenic drug…is a medication that
may deform or kill the fetus.
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Pharmacokinetics (1 of 2)
Absorption
– A drug must find its way to the site of
action.
Distribution
– A drug must then be distributed
throughout the body.
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Pharmacokinetics (2 of 2)
Biotransformation
– The process of breaking down, or
metabolizing, drugs.
Elimination
– Drugs must eventually be excreted from
the body.
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© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Drug Routes (1 of 2)
Enteral:
– Delivers medications by absorption
through the gastrointestinal tract
– Includes oral, orogastric/nasogastric,
sublingual, buccal, rectal
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Drug Routes (2 of 2)
Parenteral:
– Delivers medications via routes other
than the GI tract
– Includes intravenous, endotracheal,
intraosseous, umbilical, intramuscular,
subcutaneous, inhalation, topical
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Enteral – Examples (1 of 2)
Oral (PO)
– Good for self-administering drugs
Orogastric (OG) / Nasogastric (NG)
– Alternate method to providing PO
medications
Sublingual (SL)
– Excellent absorption without problems of
gastric acidity
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Enteral – Examples (2 of 2)
Buccal
– Between the cheek/gum
– Similar to sublingual
Rectal (PR)
– Reserved for unconscious or vomiting
patients
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Parenteral – Examples (1 of 3)
Intravenous (IV)
– Preferred route in emergencies
Endotracheal (ET)
– Alternate route in emergencies for select
medications
Intraosseous (IO)
– Alternative use in emergencies, mostly in
pediatrics
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Parenteral – Examples (2 of 3)
Umbilical
– Provides alternate access in newborns
Intramuscular (IM)
– Slower absorption than IV
Subcutaneous (SQ)
– Slower absorption than IM
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Parenteral – Examples (3 of 3)
Inhalation
– Very rapid absorption via the lungs
Topical
– Delivers drugs directly to the skin
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Most emergency
medications are given
intravenously to avoid drug
degradation in the liver.
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Drug Forms
Solid forms:
– Pills, powders, suppositories, capsules
Liquid forms:
– Solutions, tinctures, suspensions,
emulsions, spirits, elixirs, syrups
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Solid Forms
Pills
– Drugs shaped spherically to be swallowed
Powders
– Not as popular as they once were
Tablets
– Powders compressed into disk-like form
Suppositories
– Drugs mixed with a waxlike base that melts at
body temperature
Capsules
– Gelatin containers filled with powders or tiny pills
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Liquid Forms (1 of 2)
Solutions
– Water or oil-based
Tinctures
– Prepared using an alcohol extraction process
Suspensions
– Preparations in which the solid does not
dissolve in the solvent
Emulsions
– Suspensions with an oily substance in the
solvent
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Liquid Forms (2 of 2)
Spirits
– Solution of a volatile drug in alcohol
Elixirs
– Alcohol and water solvent, often with
flavoring
Syrups
– Sugar, water, and drug solutions
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Actions of Drugs
Drugs that act by binding to a receptor
site
Drugs that act by changing physical
properties
Drugs that act by chemically
combining with other substances
Drugs that act by altering a normal
metabolic pathway
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Responses to Drug
Administration (1 of 5)
Side effect
– Unintended response to a drug
Allergic reaction
– Hypersensitivity
Idiosyncrasy
– Drug effect unique to an individual
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Responses to Drug
Administration (2 of 5)
Tolerance
– Decreased response to the same amount
Cross tolerance
– Tolerance for a drug that develops after
administration of a different drug
Tachyphylaxis
– Rapidly occurring tolerance to a drug
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Responses to Drug
Administration (3 of 5)
Cumulative effect
– Increased effectiveness when a drug is given in
several doses.
Drug dependence
– The patient becomes accustomed to the drug’s
presence in his body.
Drug interaction
– The effects of one drug alter the response to
another drug.
Drug antagonism
– The effects of one drug block the response to
another drug.
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
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Responses to Drug
Administration (4 of 5)
Summation
– Also known as additive effect. Two drugs
with the same effect are given together—
similar to 1+1=2.
Synergism
– Two drugs with the same effect are given
together and produce a response greater
than the sum of their individual
responses—similar to 1+1=3.
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Responses to Drug
Administration (5 of 5)
Potentiation
– One drug enhances the effect of another.
Interference
– The direct biochemical interaction
between two drugs; one drug affects the
pharmacology of another drug.
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Factors Affecting Drug Response
Age
Body mass
Sex
Environment
Time of
administration
Pathology
Genetics
Psychology
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Drug Interactions
Drug interactions occur whenever two
or more drugs are available in the
same patient.
The interaction can increase,
decrease, or have no effect on their
combined actions.
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ
Part 1 Summary
Drug Names
Sources of Drug Products
Drug Classifications
Food & Drug Administration
Medication Administration
Properties of Drugs
Bledsoe et al., Paramedic Care Principles & Practice Volume 1: Introduction
© 2006 by Pearson Education, Inc. Upper Saddle River, NJ