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8/8/2019 Leslie Pharmacology
http://slidepdf.com/reader/full/leslie-pharmacology 1/16
2005 EMT-Intermediate Curriculum
Bridge Course
Pharmac ology andPharmac ology and
Medica t ion Admin is t ra t ionMed ica t ion Admin is t ra t ion
2005 EMT-Intermediate Curriculum
Bridge Course
Goals for the c lassGoals for the c lass
• Build a broad foundation of knowledgeregarding the characteristics and actions ofmedications
– How the body responds to medications
– Major organs and systems impacted by mostprehospital medications
• Apply the concepts of pharmacology to thedevelopment of better skill in patientassessment and management
2005 EMT-Intermediate Curriculum
Bridge Course
Object ivesObject ives
• Discuss how drugs are classified. (1)
• Explain the special considerations indrug treatment with regard to pregnant,pediatric and geriatric patients. (4)
• Discuss the EMT-I’s responsibilities andscope of management pertinent to the
administration of medications.
2005 EMT-Intermediate Curriculum
Bridge Course
Object ivesObject ives
• Describe the mechanisms of drug
action… (9)
• Defend medication administration by anEMT-I to effect positive therapeuticeffect.
2005 EMT-Intermediate Curriculum
Bridge Course
DeDe --Myst i fy ing Pharmac ologyMyst i fy ing Pharmac ology
• Drugs do not do anything new.
– They can only alter functions that are
already occurring in the body.• Replace a function, enhance a function or
interrupt a function
• Drugs will always leave residual effects.
– Even selective-site drugs!
• Albuterol and muscle tremors
2005 EMT-Intermediate Curriculum
Bridge Course
DeDe --myst i fy ing Pharmacologymyst i fy ing Pharmacology
• Drugs usually have to bind to somethingbefore anything can occur.
– Antacids bind to receptors in the stomach – Morphine binds to euphoria receptors,
nausea and vessel control receptors in thebrain
8/8/2019 Leslie Pharmacology
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2005 EMT-Intermediate Curriculum
Bridge Course
The EMTThe EMT --In te rmed ia teIn te rmed ia te ’’ssrespons ib i li t ies w i threspons ib il i t ies w i th
med ica t ion admin is t ra t ionmed ica t ion admin is t ra t ion
2005 EMT-Intermediate Curriculum
Bridge Course
EM TEM T --I Respons ib i l i t iesI Respons ib i l i t ies
• Understand how drugs in your scope ofpractice work in the body
– How they alter body functions
– Binding sites of drug classes and expected actions
– Residual effects of specific drug classes
• Keep your knowledge base current!
– New drugs are approved for use every day
– www.Rxlist.com
• Top 200 prescriptions per year
2005 EMT-Intermediate Curriculum
Bridge Course
EM TEM T --I Respons ib i l i t iesI Responsib i l i t ies
• Use drug reference literature to assist
with your understanding
– Indications, contraindications, precautions
– PDR, online resources, nursing drugguides, field guides
• Seek out information from other
professionals
– Supervising physician, pharmacists, etc.2005 EMT-Intermediate Curriculum
Bridge Course
EM TEM T --II Respons ib i l i tesRespons ib i l i tes inin
Pat ient CarePat ient Care
• Perform a comprehensive drug history
– Prescribed medications
– Over-the-counter medications
– Vitamins or herbal supplements
– Recreational/illicit substances and alcohol
– Drug interactions/reactions
2005 EMT-Intermediate Curriculum
Bridge Course
Impac t s on the EMTImpac t s on the EMT --I w i t hI w i t h
Pat ient CarePat ient Care
• Drug administration – Use the correct precautions and
administration rates – Observe for expected and unexpected
effects of the drug
– Document patient responses from the drug• Good and bad!
• Pertinent vital signs
• Use the Rights of Drug Administration
2005 EMT-Intermediate Curriculum
Bridge Course
The Rights of DrugThe Rights of Drug
Admins t ra t ionAdmins t ra t ion
• Right patient
• Right drug
• Right dose• Right route
• Right time
• Right documentation
• Right to refuse
8/8/2019 Leslie Pharmacology
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2005 EMT-Intermediate Curriculum
Bridge Course
TheThe ““ 6 Rights6 Rights ”” In Ac t ion?In Ac t ion?
Four days after an alert conscious patient was admitted tothe hospital, he died after receiving the wrong medication.
A pharmacist ordered Librium (a sedative) instead of Lithium,a drug used to manage bipolar disease. The dose for lithiumwas 300mg. The patient instead received 300mg of theLibrium, which was 60 times the safe dose for themedication. Other sedatives, antidepressants and antibioticswere administered concurrently as part of his care plan.
For two days the patient’s blood pressure continued to dropuntil he became lethargic and unresponsive.
A hospital spokesman stated that the autopsy reportconcluded that the patient died from pneumonia.
2005 EMT-Intermediate Curriculum
Bridge Course
The Basic s of Drug ClassesThe Basic s of Drug Classes
2005 EMT-Intermediate Curriculum
Bridge Course
Drug Class i f icat ionsDrug Class i f icat ions
• Drugs are classified 3 different ways:
– By body system
– By the action of the agents
– By the drug’s mechanism of action
2005 EMT-Intermediate Curriculum
Bridge Course
Drug Class Exam plesDrug Class Exam ples
• Nitroglycerin
– Body system: “Cardiac drug”
– Action of the agent: “Anti-anginal”
– Mechanism of action: “Vasodilator”
• Indications for nitroglycerin
– Cardiac chest pain
– Pulmonary edema
– Hypertensive crisis
• Which drug class best describes this drug?
2005 EMT-Intermediate Curriculum
Bridge Course
Drug ClassesDrug Classes – – another ano ther
exampleexample• Action of Agent: Anti-hypertensive drugs
– Produces similar end-results• Metoprolol
• Lisinopril
• Prazosin
• Verapamil
– None of the above drugs work on the samereceptor site
• Each drug will have different side effects and adversereactions
– Difficult to predict
– Difficult to determine how this class will interact withprehospital medications
2005 EMT-Intermediate Curriculum
Bridge Course
A bet te r w ay to c lass i fy d rugsA be t te r w ay to c lass i fy d rugs
• Mechanism of Action – Drugs in each category work on similar sites in the
body and will have similar specific effects/sideeffects
• Beta blockers: metoprolol
• ACE inhibitors: lisinopril• Alpha blockers: prazosin
• Calcium-channel blockers: verapamil
• Example: beta blocker actions and impacts – Suppress the actions of the sympathetic nervous
system
– Prehospital administration of epinephrine may notproduce as dramatic effects with a patient taking adrug in this class
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2005 EMT-Intermediate Curriculum
Bridge Course
Prehospi ta l exam ple:Prehospi ta l example:
Hyperg lycemicsHyperg lycemics
• Dextrose 50% and glucagon
– Both will raise blood glucose• Mechanism of action
– Glucagon: hormone that works in the liver toconvert stored chains of carbohydrate to glucose
– Dextrose 50%: ready-made simple sugar that isready to enter into the cell
• Which drug is considered first-line forhypoglycemia? Why?
• What are some limitations for glucagon in thepresence of severe hypoglycemia?
2005 EMT-Intermediate Curriculum
Bridge Course
Drugs in t he BodyDrugs in the Body
Anatomy and Physiology Review
Concepts of Drug Actions
2005 EMT-Intermediate Curriculum
Bridge Course
Nervous system rev iewNervous system rev iew
2005 EMT-Intermediate Curriculum
Bridge Course
Central Nervous System
Somatic Nervous SystemVoluntary control
Receptors:Alpha 1 and 2Beta 1 and 2
Neurotransmitters:Norepinephrine
Epinephrine
Sympathetic"Fight or Flight"
Neurotransmitter:Acetylcholine
Parasympathetic"Feed and Breed"
Autonomic Nervous System
Peripheral Nervous System
Nervous System
2005 EMT-Intermediate Curriculum
Bridge Course
The Sympathe t ic NSThe Sympathe t ic NS
• Which organs willrespond when you are
chased by a bear?• What signs and
symptoms will youhave as a result?
2005 EMT-Intermediate Curriculum
Bridge Course
Alpha-1Vessel Constriction:
ArteriolesVeins
Alpha-2Nerve-to-Nerve ConnectionsMinimal EMS Significance
Beta-1
Cardiac EffectsIncrease in HR, conductivity
Increase in contractions
Beta-2Dilation of bronchioles
Skeletal muscle tremorsInhibition of uterine contractions
Receptor Sites
Neurotransmitters:Norepinephrine
Epinephrine
Sympathetic
Neurotransmitter:Acetylcholine (ACh)
Parasympathetic
Autonomic Nervous System
Drug Classification Names:
• “Sympathomimetics”
• “Adrenergics”
• “Beta-2 Agonist”
• “Non-Specific Beta Agonist”
• “Beta Blocker”
8/8/2019 Leslie Pharmacology
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2005 EMT-Intermediate Curriculum
Bridge Course
The Parasympat het ic NSThe Parasympat het ic NS
• What organs will help outthe typical couch potato?
– Digestion
– Slow heart rate
– Smaller bronchioles
– Pupil size
• Normal or constricted
• This system works best atrest
Couch Potato
2005 EMT-Intermediate Curriculum
Bridge Course
Over Over --s t imu la t ion of thes t im u la t ion of the
Parasympathe t ic NSParasympathe t ic NS
• A little is a good thing, but too muchstimulation of this system leads totrouble
– Very slow heart rates
– Bronchoconstriction
– Major gastrointestional actions
• Vomiting
• Diarrhea
2005 EMT-Intermediate Curriculum
Bridge Course
Receptor Sites:Alpha 1 and 2Beta 1 and 2
Neurotransmitters:Norepinephrine
Epinephrine
Sympathetic
Heart:Decrease in HR and conduction
Lungs:Bronchoconstriction
Increase in mucus production
GI Tract:"SLUDGE"
Increase in motilityVomiting
Effects
Neurotransmitter:Acetylcholine (ACh)
Parasympathetic
Autonomic Nervous System
Drug Classification Names
• “Parasympatholytics”
• “Anticholinergics”
• “Cholinergics”
2005 EMT-Intermediate Curriculum
Bridge Course
Autonom ic Nervous SystemAutonom ic Nervous System
Sympathe t ic Receptor S i teSympathe t ic Receptor Si te
Ac t ionAc t ion
2005 EMT-Intermediate Curriculum
Bridge Course
1) Brain sends out the response via nerve paths
2) Nerve moves the response: depolarization
3) Depolarization stimulates norepinephrine sacks
• Sacks move to the end of the nerve anddump out their contents
23
2005 EMT-Intermediate Curriculum
Bridge Course
4) Norepinephrine travels across the synapse
• Attaches to a receptor on the organ, organresponds to the signal
5) Norepineprhine detaches and is deactivated
• 2 options: destroy it or move it back into its sack
2
3
4
5
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2005 EMT-Intermediate Curriculum
Bridge Course
Nervous System ReviewNervous System Review
• You are to give a dose of a parasympatholytic.What is it expected to do?
– Bronchodilation
– Increase GI motility
– Stimulate vomiting
– Increase HR
• Is a parasympatholytic the same as asympathomimetic?
2005 EMT-Intermediate Curriculum
Bridge Course
Nervous System ReviewNervous System Review
5 minutes after you gave a non-specificbeta agonist, you notice that thepatient is complaining of palpitations.
This effect is considered to be:
a) A desired effect of the drug
b) An expected side effect of the drug
c) An unpredictable, adverse effect of thedrug
2005 EMT-Intermediate Curriculum
Bridge Course
Nervous System ReviewNervous System Review
• What other side effects or adverse
reactions would you expect to see in apatient after giving them an adrenergicdrug?
– Muscle tremors
– Tachycardia
– Elevated BP
– Chest discomfort2005 EMT-Intermediate Curriculum
Bridge Course
Nervous System ReviewNervous System Review
• A patient is taking atenolol, a Beta-1specific blocker. What is the expectedeffects of this drug? – Lowered HR
– Decrease in contraction and conduction
• What would be an expected side effectof the drug? – Dizziness when standing
2005 EMT-Intermediate Curriculum
Bridge Course
EM TEM T --I Nervous System DrugsI Nervous System Drugs
• Epinephrine 1:1,000
– Catecholamine, adrenergic, non-specific beta agonist
• Epinephrine, USP, 1:10,000
– Same as above!• Albuterol
– Beta-2 agonist
• Atropine
– Parasympatholytic
• Ipatroproprium Bromide (Atrovent)
– Parasympatholytic bronchodilator2005 EMT-Intermediate Curriculum
Bridge Course
Drug Mechanism sDrug Mechanism s
of Ac t iono f Ac t ion
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2005 EMT-Intermediate Curriculum
Bridge Course
Phases of Drug Act iv i tyPhases of Drug Act iv i t y
• Pharmaceutical – Disintegration and dissolution
• Pharmacokinetic
– How the drug gets in, how it reaches thetarget and how it gets out of the body
• Pharmacodynamic
– The response of the tissue to the drug
2005 EMT-Intermediate Curriculum
Bridge Course
Pharmac eut ic a l PhasePharmac eut ic a l Phase
• Disintegration – Breakdown of the solid form of the
medication
• Dissolution
– Drug goes into solution form and is able tobe absorbed
– The more rapid this step, the faster thedrug will be absorbed
2005 EMT-Intermediate Curriculum
Bridge Course
Pharmacok ine t icsPharmacok ine t ics
• Absorption
• Distribution
• Metabolism
• Excretion
2005 EMT-Intermediate Curriculum
Bridge Course
Absorpt ionAbsorpt ion
Drug Fact ors ThatDrug Fact ors That
Impac t Absorp t ionImpac t Absorp t ion
• Fast, efficient absorption is achieved withthe following:
– High surface area of the tissue – Rich blood supply at the tissue
– Thin membranes between the tissue and thebloodstream
• Drug solubility
– Lipid soluble drugs absorb faster in tissuesand cells than water soluble drugs
2005 EMT-Intermediate Curriculum
Bridge Course
Other Drug Fact ors ThatOt her Drug Fact ors That
Impac t Absorp t ionImpac t Absorp t ion
• Drug concentration
– High concentrations of the drug at the
tissue will achieve better absorption as well• pH of the drug
– Glucagon does not absorb into cells readily
• Requires very low or very high pH to break itdown
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2005 EMT-Intermediate Curriculum
Bridge Course
Pat ien t Fac to rs Impac t ingPat ien t Fac to rs Impac t ing
Absorpt ionAbsorpt ion
• Decreased circulation – Hypothermia
– Shock
• Decreased cardiacoutput – CHF
– Significant MI
Absorpt ion RatesAbsorpt ion Rates
Intracardiac
Endotracheal,Inhalation, IO, IV
Sublingual
Rectal
Topical
Intramuscular
Oral
Subcutaneous
2005 EMT-Intermediate Curriculum
Bridge Course
Oral Absorpt ion SpeedsOral Absorpt ion Speeds
• Elixirs, syrups
• Suspensions
• Powders
• Capsules
• Tablets
• Coated tablets
• Enteric-coated tablets
Fast
Slow
2005 EMT-Intermediate Curriculum
Bridge Course
Pharmac ology StudyPharmac ology St udy
Guide, #4Guide, #4
• A patient with an exacerbation of hischronic herniated disks – Oral Percocet taken 1 hour before EMS
arrival• No change in pain
– Has there been enough time for thePercocet to be absorbed?
– Should morphine be given to the patient?• Explain the rationale for the decision
Absorpt ion Pr inc ip les for theAbsorpt ion Pr inc ip les for the
EM TEM T --II
• IV is used as the primary route
– IV drugs already in solution form
– Achieving drug levels are predictable• Everything that is administered is already in the
circulation
– Higher chance of toxicity
• Absorption and delivery is immediate
2005 EMT-Intermediate Curriculum
Bridge Course
Absorpt ion Pr inc ip les for Absorpt ion Pr inc ip les for
the EMTthe EMT --II
• Intramuscular (IM) – “second line” route – Highly vascular, but not as direct a route
for administration – IM routes are utilized as a back-up when IV
access is unobtainable
• SQ – Limited #s of BV and slower absorption
– Drugs must have a higher concentration in orderto be given in this route
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2005 EMT-Intermediate Curriculum
Bridge Course
More Appl icat i ons of More Appl icat ions of
Absorpt ionAbsorpt ion
2005 EMT-Intermediate Curriculum
Bridge Course
Ni t rog lycer inNi t rog lycer in
• How does the drug come packaged? – As a tablet
• Nitroglycerin forms and absorption rates
– SL: 1-3 minutes
– Ointment/transdermal: 30 minutes
– Oral/tablet: 15-40 minutes
– IV: immediate!
2005 EMT-Intermediate Curriculum
Bridge Course
Epinephr ine Absorpt ionEpinephr ine Absorpt ion• What is the concentration and dosing time for
subcutaneous and IV epinephrine? – SQ - 1:1000 with repeat doses every 3-5 minutes
– IV - 1:10,000 with repeat doses every 3-5 minutes
• Why is there a need for 2 differentconcentrations? – Epinephrine is a short-lived drug and will break down
quickly
– SQ absorption is significantly slower than IV
– A higher concentration of the drug will assure thatenough of the active drug will still be available after it isabsorbed
2005 EMT-Intermediate Curriculum
Bridge Course
Absorpt ion at t he Cel lAbsorpt ion at t he Cel l
2005 EMT-Intermediate Curriculum
Bridge Course
Four Pat hs of Cel lu lar Four Pat hs of Cel lu lar
Absorpt ionAbsorpt ion
• Membrane pores
– Drug must be very, very small in order to enter
– Rare site of absorption• Diffusion
– Movement through the membrane with aconcentration gradient
– No energy required to move the drug
– Most common route of entry for drugs (lipidsoluble)
2005 EMT-Intermediate Curriculum
Bridge Course
DiffusionDiffusion
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2005 EMT-Intermediate Curriculum
Bridge Course
Four Pat hs of Cel lu lar Four Pat hs of Cel lu lar
Absorpt ionAbsorpt ion
• Facilitated Diffusion – Commonly used for moderate-sized drugs and
water soluble drugs• Morphine, dextrose, amiodarone, diphenhydramine
– Drug forms a complex with a protein in themembrane, which allows the gates of themembrane to open
• Active Transport – Movement of a drug against a concentration
gradient
– Requires the use of energy to let the drug in
2005 EMT-Intermediate Curriculum
Bridge Course
Fac i l i ta tedFac i l i ta tedDiffusionDiffusion
2005 EMT-Intermediate Curriculum
Bridge Course
Distr ibut ionDis tr ibut ion
Pharmacok ine t ics :Pharmacok ine t ics :
Dis t r ibut ionDis tr ibut ion
• Definition: how the drug gets from the bloodto the target cell or tissue
• Plight of the drug bolus
– Some of the drug will seek out and bind with cellreceptors
• There may not be enough cell receptors for the drug
– The rest of the drug will go to staging andutilized as replacements
• Drug reservoirs
2005 EMT-Intermediate Curriculum
Bridge Course
Pharmacok ine t ics :Pharmacok ine t ics :
Dis t r ibut ionDis tr ibut ion
• Types of drug reservoirs
– Fat cells (for fat soluble drugs)
• Longer storage time
• Marijuana THC can stay in the body up to 6 months with
just one dose
– Plasma proteins (all other drugs)
• “Mobile storage”
• Release of the drug is more immediate and replacement
at cell receptors is more rapid
Barr iers to Dis t r i but ionBarr iers to Dis t r ibut ion
• Blood-Brain Barrier
– Selective site for drugs
– Capillary cells packed tightly
together
– Only allows fat-soluble drugs andsmall molecules through
• Placental Barrier
– Only lipid soluble or free-formdrugs can get through
8/8/2019 Leslie Pharmacology
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2005 EMT-Intermediate Curriculum
Bridge Course
Bio t rans fo rmat ionBio t rans fo rmat ion
(Drug Met abol ism)(Drug Met abol ism)
Pharmacok ine t ics :Pharmacok ine t ics :
B io t rans fo rmat ionB io t rans fo rmat ion
• Drugs must be in an active form before
they can work at a cell receptor
– Most prehospital drugs are packaged in anactive form and result in a faster onset of thedrug
• “Active metabolite”
– Other drugs must be transported to the liverto be “de-activated” before elimination
2005 EMT-Intermediate Curriculum
Bridge Course
Fact ors Al ter ing DrugFact ors Al ter ing Drug
Metabol ismMetabol ism
• Age
– Pediatric “growth spurts” may increasedrug metabolism
– The very young and very old havediminished liver function and may developdrug toxicity
• Body mass and gender
– Fat distribution and percentage differences
2005 EMT-Intermediate Curriculum
Bridge Course
Fact ors Al ter ing DrugFact ors Al ter ing Drug
Metabol ismMetabol ism
• Pathologic state
– Circulatory problems, CHF may slow drugdistribution
• Genetic factors
– Enzyme systems in some may be slower
– More susceptibility to adverse reactions ortoxic effects
2005 EMT-Intermediate Curriculum
Bridge Course
Excre t ionExcre t ion
Pharmacok ine t ics : Excre t ionPharmacok ine t ics : Excre t ion
• Bile
– Drugs turned intoinactive metabolitesby the liver
– Dumped into theduodenum andexcreted by the feces
• Expired air
– Alcohol andvolatilegases
• Breast milk
– Narcotics
Routes o f El iminat ionRoutes o f El iminat ion
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2005 EMT-Intermediate Curriculum
Bridge Course
Routes of E l iminat ionRoutes of E l iminat ion
• Urine
– Drugs must be in a “deactivated” formbefore they are eliminated by the kidneys
– Water-soluble drugs are removed easily
– Fat soluble drugs must be more “water-friendly” if the kidneys are going to get ridof them
• This transformation occurs in the liver
2005 EMT-Intermediate Curriculum
Bridge Course
Pharmacodynamics:Pharmacodynamics:
How the tissues and cellsHow the tissues and cells
respond to a drugrespond to a drug
2005 EMT-Intermediate Curriculum
Bridge Course
Theor ies of Drug Act ionTheor ies of Drug Act ion
2005 EMT-Intermediate Curriculum
Bridge Course
DrugDrug --Receptor In te rac t ionReceptor In te rac t ion
Drug classes are sometimes named by
the type of cell receptor with which theyinteract
• “Beta blockers”
• “Opiate drugs”
• “Anticholinergics”
2005 EMT-Intermediate Curriculum
Bridge Course
DrugDrug --Receptor In te rac t ionReceptor In te rac t ion
Drug classes are sometimes named by theiractions on a cell receptor
• “Agonist” drugs – after binding, the drug willstimulate a response – Albuterol: “Beta-2 agonist”
• “Antagonist” drugs – after binding, the drugwill prevent a response – Narcan: “narcotic antagonist”
– Benadryl: anti-histamine
2005 EMT-Intermediate Curriculum
Bridge Course
Pharmac ology StudyPharmac ology St udy
Guide, #4Guide, #4
• Back pain guy – Does Percocet work on the same receptors
as morphine?• How could these impact the patient (sideeffects)?
– New medication options• Nubain and Toradol
– Do these work differently?
– How will these impact the patient’sconditions?
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2005 EMT-Intermediate Curriculum
Bridge Course
MorphineMorphine
versusversus
NubainNubain
• Morphine binding to2 receptors
– Activates both
• Nubain binds to both
– Activates only one
– Sits in the other andblocks agonists fromstimulating it MS
Morphine
Nubain
- Decrease pain,sedate and dropconsciousness- Drop RR
- Decrease pain,sedate and dropconsciousness
- Decrease pain,sedate and dropconsciousness
NoResponse
2005 EMT-Intermediate Curriculum
Bridge Course
DrugDrug --ResponseResponse
Relat ionshipRelat ionship
• Drugs are studied for the following: – Plasma levels
• How fast they reach active levels
– Biologic half-life
• How long it takes to break down half of the drug
– Minimum effective concentration
• How much of the drug it takes to create a response
– Therapeutic threshold
• How much of the drug is too much, or toxic
2005 EMT-Intermediate Curriculum
Bridge Course
MinimumEffectiveConcentration
TherapeuticThreshold
PlasmaLevels
DrugDrug --
Response:Response:
L idoca ineL idoca ine
• Graph: single bolus of lidocaine
• Relatively rapid breakdown of the drug to sub-therapeutic levels – Half-life is 7-30 minutes
• Dosing regimen is every 3-5 minutes in order to
keep the drug at or near therapeutic levels
2005 EMT-Intermediate Curriculum
Bridge Course
Lidoca ineL idoca ine
Top Graph
• Multiple bolusescreate variedtherapeutic levels – Blue line
Lower Graph
• Bolus with a drip: – Smaller constant
level of infusionwill provide justenough lidocaineto replaceelements of thebolus that wasbroken down
2005 EMT-Intermediate Curriculum
Bridge Course
DrugDrug --
Response:Response:
L idoca ineL idoca ine
• Lidocaine is broken down by the liver
• What will happen if the same dosing regimen for thedrug is used in patients with liver failure?
– Takes longer to break down the drug (increase in its half life)
– Toxic levels can occur in lidocaine’s target organs
• Heart – asystole
• Brain – altered levels of consciousness
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2005 EMT-Intermediate Curriculum
Bridge Course
Drug In terac t ion Var iab lesDrug In terac t ion Var iab les
• Intestinal absorption
• Competition for plasmaprotein binding
• Drug metabolism
– “Biotransformation”
• Action at the receptorsite
• Renal excretion
• Alteration of electrolytebalance
• Drug-druginteractions
• Other druginteractions
– Alcohol consumption
– Cigarette smoking
2005 EMT-Intermediate Curriculum
Bridge Course
Pharmac ology Case StudyPharmac ology Case St udy
2005 EMT-Intermediate Curriculum
Bridge Course
Case Stu dyCase Stu dy
You respond to “Jan,” a 45 year-old female who wasstung by a bee while at a family picnic. She is lying inthe grass field. She is conscious but shaking. She hashives on her arms, chest and legs.
A family member tells you that they administered herEpi-Pen 5 minutes ago.
She is conscious. Her vital signs include a respiratoryrate of 24, heart rate of 110 and a blood pressure of 156/70.
2005 EMT-Intermediate Curriculum
Bridge Course
More Pat ient In form at ion
Jan has a history of “severe” reactions to bee stings.Her lips appear swollen but her family members statethat “her whole face was swollen before we gave her theEpi-Pen.”
Her lung sounds are clear.
2005 EMT-Intermediate Curriculum
Bridge Course
Embel l ishment !
• Would you expect a change in Jan’sresponse to epinephrine if she… – Was 5 years old?
– Was 20 and pregnant?
– Was 65 (and not pregnant)?
– Was old, pregnant, and acted like she was 5?
Just Kidding!!
2005 EMT-Intermediate Curriculum
Bridge Course
A New EMTA New EMT--I T rea tmentI T rea tment
Opt ion for Anaphy lax isOpt ion for Anaphy lax is
• Benadryl – Class: “Antihistamine”
– Antagonist to histamine• Competes for the same receptor sites as
histamine
• Does not directly control the release ofhistamine
• Effectiveness is dependent on concentration
– Higher levels of histamine will be more likelyto bind to the receptor than Benadryl
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2005 EMT-Intermediate Curriculum
Bridge Course
Benadryl v. Epinephr ineBenadryl v. Epinephri ne
• When should you give one medicationover the other? Why? – Benadryl not as effective with massive
histamine release
– Epinephrine binds to other cell receptors incritical areas
• Beta receptors
• More potent response and will override thehistamine response
2005 EMT-Intermediate Curriculum
Bridge Course
Benadry l Act ionsBenadry l Ac t ions
• Half-l ife
– 2.5 - 7 hours
• Drug effects
– Rapid onset with widedistribution
– Extensively broken down
by the liver
– Excreted extensively by
the kidneys
– Also has anticholinergic
activity
• How will this drug
act differently inchildren?
• How will it impactthe elderly?
• With which medicalconditions will itcause more trouble?
Drugs in K idsDrugs in K ids
• Less than one year
– Lower levels of plasma protein
• Increased likelihood for drugs to be in a free-form state
– More potent effects of the drug
– Kidneys and liver are less developed
• Potentially slower activation and eliminationof drugs
2005 EMT-Intermediate Curriculum
Bridge Course
Kids and DrugsKids and Drugs
• Over 1 year
– Liver enzymes more active than an adult
– Faster work in the kidneys than an adult
• Later childhood causes a faster elimination of drugs
– Dosing for drugs are based on the child’s weight
• More proportional response
PregnancyPregnancy
Considerat ionsConsiderat ions
• 1st trimester – Lipid soluble drugs can cross into the placenta
– Immature fetal liver and kidneys may store drugs longer
• Later pregnancy – Higher HR, CO = faster absorption and onset of drugs
– Increased fatty tissue may cause more storage of lipid-solubledrugs
– Drug dependency by the fetus if the mother is addicted to opiatedrugs
• During labor – May depress respirations in the neonate
The ElderlyThe Elderly
• Decreased cardiac output and metabolism
– Longer drug effects (pain medications)
– Less filtration through the kidneys – keepsdrugs in circulation longer
• More body fat and less total body water
– Stores more fat-soluble drugs
– Higher concentration of drugs in the body
• Decreased plasma proteins
– More drugs circulating in their free-form state
8/8/2019 Leslie Pharmacology
http://slidepdf.com/reader/full/leslie-pharmacology 16/16
2005 EMT-Intermediate Curriculum
Bridge Course
The hal f -l i fe o f Val ium in a 20
year-o ld las ts approx im ate ly 20
hours .
For a person in the i r 80s, th is
hal f -l i fe ex t ends to 90 hours !
2005 EMT-Intermediate Curriculum
Bridge Course
Managing Contro l ledManaging Cont ro l led
SubstancesSubstances
• Ensuring the security of them• Requirements for locking a controlled
substance
• Accounting of drug inventory
• Wasting a controlled substance
• DEA forms
• Violation reporting
2005 EMT-Intermediate Curriculum
Bridge Course
Pharmaco logy Ac t iv i tyPharmaco logy Ac t iv i t y
Find a partner and grab one medication out of thegrab bag. Create a singles ad-style of profile for
your medication, including indications,contraindications, precautions and how the drug
works in the body.
Be prepared to share your “singles ad” to the class.