Introduction to Drug Therapy
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Transcript of Introduction to Drug Therapy
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Nursing 3703Nursing 3703
Pharmacology in NursingPharmacology in Nursing
Introduction to Drug TherapyIntroduction to Drug Therapy
Linda SelfLinda Self
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Grouping of DrugsGrouping of Drugs
Names may reflect the conditions for whichNames may reflect the conditions for which
they are used (e.g. antidepressants)they are used (e.g. antidepressants)
May reflect their chemical characteristicsMay reflect their chemical characteristics(benzodiazepines)(benzodiazepines)
May reflect the effects on body systemsMay reflect the effects on body systems
(central nervous system depressants)(central nervous system depressants)
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Prototype DrugsPrototype Drugs
Individual drugs that represent groups ofIndividual drugs that represent groups of
drugs are calleddrugs are called PrototypesPrototypes
May be the first drugs of this group to beMay be the first drugs of this group to bedeveloped (e.g., penicillin for antibiotics,developed (e.g., penicillin for antibiotics,
morphine for opioid analgesics)morphine for opioid analgesics)
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Drug NamesDrug Names
Generic Name is related to the chemicalGeneric Name is related to the chemical
name and is independent of thename and is independent of the
manufacturer (e.g., sertraline)manufacturer (e.g., sertraline)
Trade name is designated and patented byTrade name is designated and patented by
the manufacturer (e.g., Zoloft)the manufacturer (e.g., Zoloft)
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American Drug Laws andAmerican Drug Laws and
AmendmentsAmendments
1938 Food, Drug and Cosmetic Act required1938 Food, Drug and Cosmetic Act required
proof of safety, authorized factoryproof of safety, authorized factory
inspections, established penalties forinspections, established penalties for
fraudulent claimsfraudulent claims
1952 Durham-Humphrey Amendment1952 Durham-Humphrey Amendment
designated drugs that must be prescribeddesignated drugs that must be prescribed
by a physician and dispensed by aby a physician and dispensed by a
pharmacist (e.g., controlled substances,pharmacist (e.g., controlled substances,
etc.)etc.)
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American Drug Laws cont.American Drug Laws cont.
1970 Comprehensive Drug Abuse1970 Comprehensive Drug Abuse
Prevention and Control Act; Title II,Prevention and Control Act; Title II,
Controlled Substances ActControlled Substances Act
Categorized according to potential for abuseCategorized according to potential for abuse
Regulated distribution of narcotics and otherRegulated distribution of narcotics and other
drugs of abusedrugs of abuse DEA charged w/enforcing the ControlledDEA charged w/enforcing the Controlled
Substances ActSubstances Act
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Categories of Controlled SubstancesCategories of Controlled Substances
Schedule Inot approved for medical useSchedule Inot approved for medical use
and have high abuse potentials; LSD,and have high abuse potentials; LSD,
heroin, peyote, ecstasy (3,4 methyenedioxy-heroin, peyote, ecstasy (3,4 methyenedioxy-
methamphetamine)methamphetamine)
Schedule IIused medically. High abuseSchedule IIused medically. High abuse
potential (methadone, meperidine, cocaine,potential (methadone, meperidine, cocaine,
pentobarbital, Tylox)pentobarbital, Tylox)
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Categories of Controlled SubstancesCategories of Controlled Substances
continuedcontinued
Schedule III-less potential for abuse than ISchedule III-less potential for abuse than Iand II but may lead to psychological orand II but may lead to psychological orphysical dependence (Vicodin, Tylenol withphysical dependence (Vicodin, Tylenol with
codeine)codeine) Schedule IV-drugs have some potential forSchedule IV-drugs have some potential for
abuse (Valium, Dalmane, Klonopin)abuse (Valium, Dalmane, Klonopin)
Schedule V-contain moderate amounts ofSchedule V-contain moderate amounts ofcontrolled substances. An example iscontrolled substances. An example isLomotil (atropine and diphenoxylate)Lomotil (atropine and diphenoxylate)
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Pregnancy CategoriesPregnancy Categories
Cat. A-studies in pregnant women failed toCat. A-studies in pregnant women failed to
show risk to the fetusshow risk to the fetus
Cat. B- animal studies have failed to show aCat. B- animal studies have failed to show arisk to the fetus but there are no adequaterisk to the fetus but there are no adequate
studies in womenstudies in women
Cat. C-animal studies have shown anCat. C-animal studies have shown anadverse effect on the fetus, no adequateadverse effect on the fetus, no adequate
human studies, benefits may outweigh riskshuman studies, benefits may outweigh risks
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Pregnancy Categories cont.Pregnancy Categories cont.
Cat. D-positive evidence of human fetal riskCat. D-positive evidence of human fetal risk
Cat. X-animal or human studies have shownCat. X-animal or human studies have shown
fetal abnormalities or toxicityfetal abnormalities or toxicity
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PharmacokineticsPharmacokinetics
Involves drug movement through the bodyInvolves drug movement through the body
to reach sites of action, metabolism, andto reach sites of action, metabolism, and
excretionexcretion
Specific processes are absorption,Specific processes are absorption,
distribution, metabolism and excretiondistribution, metabolism and excretion
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Pharmacokinetics-Drug TransportPharmacokinetics-Drug Transport
PathwaysPathways
Three main pathways of drug movementThree main pathways of drug movementacross cell membrancesacross cell membrances
1.1. Most common isMost common is direct penetrationdirect penetration by lipidby lipidsoluble drugssoluble drugs
2.2. 22ndnd pathway involves passage throughpathway involves passage throughprotein channelsprotein channels. Gates open and close. Gates open and close
either by voltage gating or by assist ofeither by voltage gating or by assist ofchemical substances (Na+ and K+ ionschemical substances (Na+ and K+ ionsaffecting some cardiac drugs)affecting some cardiac drugs)
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Drug Transport Pathways cont.Drug Transport Pathways cont.
3. 33. 3rdrd is byis by carrier proteinscarrier proteins that transportthat transport
molecules from one side of the cellmolecules from one side of the cell
membrane to the other. An example wouldmembrane to the other. An example would
be oral drugs that carry hormones to theirbe oral drugs that carry hormones to their
sites of actionsites of action
(see text for details)(see text for details)
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PharmacokineticsPharmacokinetics
Absorption-process that occurs from theAbsorption-process that occurs from thetime a drug enters the body to the time ittime a drug enters the body to the time itenters the bloodstream to be circulatedenters the bloodstream to be circulated
Factors affecting absorption include: dosageFactors affecting absorption include: dosageform, route of administration, blood flow toform, route of administration, blood flow tothe site of administration, gastrointestinalthe site of administration, gastrointestinal
function, presence of food or other drugsfunction, presence of food or other drugs For many medications, food in the stomachFor many medications, food in the stomach
slows absorptionslows absorption
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BioavailabilityBioavailability
Is the portion of a dose that reaches theIs the portion of a dose that reaches the
systemic circulation and is available to actsystemic circulation and is available to act
on body cellson body cells
IV administration is 100% bioavailableIV administration is 100% bioavailable
Subcutaneous administrations has moreSubcutaneous administrations has more
rapid absorption than does the oral routerapid absorption than does the oral route Mucous membranes allow for rapid andMucous membranes allow for rapid and
direct absorption into the bloodstreamdirect absorption into the bloodstream
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DistributionDistribution
Involves the transport of drug moleculesInvolves the transport of drug molecules
within the bodywithin the body
After the drug is absorbed into theAfter the drug is absorbed into thebloodstream, it is carried by the blood orbloodstream, it is carried by the blood or
tissue fluids to its sites of pharmacologictissue fluids to its sites of pharmacologic
action, metabolism and excretionaction, metabolism and excretion
Protein binding is an important factor in drugProtein binding is an important factor in drug
distributiondistribution
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Distribution cont.Distribution cont.
Drug distribution into the CNS is limited becauseDrug distribution into the CNS is limited because
of the blood-brain barrierof the blood-brain barrier
Blood-brain barrier is composed of capillaries withBlood-brain barrier is composed of capillaries with
tight walls which limits movement of drugtight walls which limits movement of drugmolecules into brain tissuemolecules into brain tissue
Only drugs that are lipid soluble or have aOnly drugs that are lipid soluble or have a
transport system can cross the blood-brain barriertransport system can cross the blood-brain barrierand reach therapeutic concentrations in brainand reach therapeutic concentrations in brain
tissuetissue
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Distribution cont.Distribution cont.
Drug distribution during pregancy andDrug distribution during pregancy and
lactation is unique as most drugs cross thelactation is unique as most drugs cross the
placenta or in the case of lactation, passplacenta or in the case of lactation, pass
into breastmilkinto breastmilk
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Protein bindingProtein binding
Most drugs form a compound with plasmaMost drugs form a compound with plasma
proteins, mainly albumin, which act as carriersproteins, mainly albumin, which act as carriers
Only the free or unbound portion of a drug acts onOnly the free or unbound portion of a drug acts on
body cellsbody cells
As unbound drug acts on cells, the decrease inAs unbound drug acts on cells, the decrease in
plasma drug level causes some of the bound drugplasma drug level causes some of the bound drug
to be releasedto be released Protein binding allows a part of a drug dose to beProtein binding allows a part of a drug dose to be
stored and released as neededstored and released as needed
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MetabolismMetabolism
Method by which drugs are inactivated orMethod by which drugs are inactivated or
biotransformed by the bodybiotransformed by the body
Some drugs yield metabolites that are alsoSome drugs yield metabolites that are alsoactive and exert effects on the body untilactive and exert effects on the body until
they are excreted (normeperidine)they are excreted (normeperidine)
Most drugs are lipid soluble which aids theirMost drugs are lipid soluble which aids theirpassage across the cell membranepassage across the cell membrane
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Metabolism cont.Metabolism cont.
Excretion usually is by kidneys. Need to beExcretion usually is by kidneys. Need to be
water soluble for this to occur. Thus, onewater soluble for this to occur. Thus, one
function of metabolism is to convert fatfunction of metabolism is to convert fat
soluble medications to water soluble ones.soluble medications to water soluble ones.
Hepatic drug metabolism or clearance is aHepatic drug metabolism or clearance is a
major mechanism for terminating drugmajor mechanism for terminating drug
action and eliminating drug molecules fromaction and eliminating drug molecules from
the bodythe body
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Metabolism cont.Metabolism cont.
Most drugs are metabolized by theMost drugs are metabolized by the
cytochrome P450 enzymes in the livercytochrome P450 enzymes in the liver
Liver contains complex system of enzymes,Liver contains complex system of enzymes,three of which are key in the metabolism ofthree of which are key in the metabolism of
medications/drugsmedications/drugs
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Cytochrome p450Cytochrome p450
CYP enzymes catalyze the chemical reactionsCYP enzymes catalyze the chemical reactions
which ultimately metabolize the medicationswhich ultimately metabolize the medications
With chronic administration (greater than 1-3With chronic administration (greater than 1-3
weeks), some drugs stimulate hepatocytes toweeks), some drugs stimulate hepatocytes toproduce larger amounts of drug metabolizingproduce larger amounts of drug metabolizing
enzymes (inducers). Enzyme induction acceleratesenzymes (inducers). Enzyme induction accelerates
drug metabolism. Result is that larger doses of thedrug metabolism. Result is that larger doses of the
drug may be need for therapeutic effects.drug may be need for therapeutic effects.
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Cytochrome p450Cytochrome p450
Enzyme inhibition may occur with concurrentEnzyme inhibition may occur with concurrent
administration of two or more drugs that competeadministration of two or more drugs that compete
for the same metabolizing enzymes (e.g., Dilantin,for the same metabolizing enzymes (e.g., Dilantin,
EES, Tagamet)EES, Tagamet) Oral meds are generally absorbed by the GI tractOral meds are generally absorbed by the GI tract
and carried to the liver. Drug may undergoand carried to the liver. Drug may undergo
extensive metabolism leaving little for systemicextensive metabolism leaving little for systemic
use. This is called theuse. This is called the first pass effect.first pass effect.
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ExcretionExcretion
Refers to the elimination of a drug from theRefers to the elimination of a drug from the
bodybody
Most are excreted by the kidneys althoughMost are excreted by the kidneys althoughsome are excreted in the bile then the fecessome are excreted in the bile then the feces
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Serum Drug LevelsSerum Drug Levels
Lab measurement of the amount of a drugLab measurement of the amount of a drugin the blood at a particular timein the blood at a particular time
Minimum effective concentration (MEC)-Minimum effective concentration (MEC)-
must be present before a drug exerts itsmust be present before a drug exerts itspharmacologic action on body cellspharmacologic action on body cells
Duration of action-Duration of action-time during which serumtime during which serum
drug levels are at or above the MEC (maydrug levels are at or above the MEC (maymeasure serum drug levels when the drugsmeasure serum drug levels when the drugshave a low therapeutic index)have a low therapeutic index)
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Pharmacodynamics--ReceptorsPharmacodynamics--Receptors
Involves drug actions on target cells and theInvolves drug actions on target cells and the
resulting alterations in cellular biochemicalresulting alterations in cellular biochemical
reactionsreactions
Most drugs chemically bind with receptors atMost drugs chemically bind with receptors at
the cellular levelthe cellular level
Drug-receptor complex initiatesDrug-receptor complex initiates
physiochemical reactions that stimulate orphysiochemical reactions that stimulate or
inhibit cellular functionsinhibit cellular functions
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Pharmacodynamics-receptorsPharmacodynamics-receptors
Receptors vary in type, location, numberReceptors vary in type, location, number
and functional capacityand functional capacity
When drug molecules chemically bind withWhen drug molecules chemically bind withcell receptors, pharmacologic effects resultcell receptors, pharmacologic effects result
from agonism or antagonismfrom agonism or antagonism
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Pharmacodynamics-receptorsPharmacodynamics-receptors
Agonists-Agonists-are drugs that produce effects similar toare drugs that produce effects similar to
those produced by naturally occurring hormones,those produced by naturally occurring hormones,
neurotransmitters and others. Agonists mayneurotransmitters and others. Agonists may
accelerate or slow normal cellular processesaccelerate or slow normal cellular processesdepending on the type of receptor activated.depending on the type of receptor activated.
AntagonistsAntagonistsdrugsdrugsthat inhibit cell function bythat inhibit cell function by
occupying receptor sites.occupying receptor sites.
Not all drugs act on receptors. Examples include:Not all drugs act on receptors. Examples include:
antacids, osmotic diuretics, chelators.antacids, osmotic diuretics, chelators.
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Variables that affect drug actionsVariables that affect drug actions
DosageDosage
RouteRoute
Drug-diet interactions. Food may slowDrug-diet interactions. Food may slowabsorption or foods may actually interactabsorption or foods may actually interact
with certain medications (tyramine and MAOwith certain medications (tyramine and MAO
inhibitors; tetracycline and milk products;inhibitors; tetracycline and milk products;
ingestion when taking certainingestion when taking certain
antihypertensive medications)antihypertensive medications)
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Variables affecting drug actionsVariables affecting drug actions
Drug-drug interations-additive effects suchDrug-drug interations-additive effects such
as seen with sedatives and ethanol.as seen with sedatives and ethanol.
Synergism as seen with acetaminophen andSynergism as seen with acetaminophen and
codeine.codeine.
Antidotedrug can be given to antagonizeAntidotedrug can be given to antagonize
the toxic effects of another drugthe toxic effects of another drug
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Variables that affect drug actionsVariables that affect drug actions
AgeAge
PregnancyPregnancy
Body weightBody weight Gender-hormonal effectsGender-hormonal effects
Pathologic conditionsPathologic conditions
Placebo responsePlacebo response
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Variables that affect drug actionsVariables that affect drug actions
Genetics-hepatic drug metabolizingGenetics-hepatic drug metabolizing
enzymes===acetyltransferase. Rapid acetylatorsenzymes===acetyltransferase. Rapid acetylators
may need larger than usual dosages andmay need larger than usual dosages and
conversely, smaller doses if slow acetylatorsconversely, smaller doses if slow acetylators Glucose-6-phosphate deficiencydevelopGlucose-6-phosphate deficiencydevelop
hemolytic anemia if take antimalarials orhemolytic anemia if take antimalarials or
sulfonamidessulfonamides
EthnicityACE inhibitors in African AmericansEthnicityACE inhibitors in African Americans
Tolerance and cross toleranceTolerance and cross tolerance
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Adverse effects of drugsAdverse effects of drugs
CNSCNS
GIGI
Hematologic-anticonvulsantsHematologic-anticonvulsants
Hepatic-acetaminophen, INHHepatic-acetaminophen, INH
Nephrotoxicity-aminoglycosides, NSAIDSNephrotoxicity-aminoglycosides, NSAIDS
HypersensitivityHypersensitivity
Drug fever-fever associated w/administration ofDrug fever-fever associated w/administration of
some antimicrobials, atropine or TCAssome antimicrobials, atropine or TCAs
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Adverse Drug EffectsAdverse Drug Effects
Drug dependencyDrug dependency
IdiosyncrasyIdiosyncrasy
CarcinogenicityCarcinogenicity teratogenicityteratogenicity
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ToxicologyDrug OverdosageToxicologyDrug Overdosage
General managementGeneral management
1.1. CPRCPR
2.2. ETTETT
3.3. IVIV4.4. Check blood sugar, drug screen, liver and kidneyCheck blood sugar, drug screen, liver and kidney
functionfunction
5.5. CharcoalCharcoal
6.6. Narcan or possibly antidotesNarcan or possibly antidotes7.7. May alkalinize the urine to prevent kidneyMay alkalinize the urine to prevent kidney
damagedamage
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Antidotes for Selected TherapeuticAntidotes for Selected Therapeutic
DrugsDrugs
Acetaminophen-mucomystAcetaminophen-mucomyst
Digoxin-digibindDigoxin-digibind
Beta blockers-Glucagon (increasesBeta blockers-Glucagon (increasesmyocardial contractility)myocardial contractility)
Phenothiazines-benadryl (EPS)Phenothiazines-benadryl (EPS)
Coumadin-vitamin KCoumadin-vitamin K
Heparin-protamine sulfateHeparin-protamine sulfate
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Antidotes cont.Antidotes cont.
BenzodiazepinesflumazenilBenzodiazepinesflumazenil
Cholinergics-atropineCholinergics-atropine
Calcium channel blockerscalciumCalcium channel blockerscalciumgluconategluconate
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General Principles of accurate drugGeneral Principles of accurate drug
administrationadministration
Six RightsSix Rights
1.1. Right patientRight patient
2.2. Right drugRight drug3.3. Right doseRight dose
4.4. Right routeRight route
5.5. Right timeRight time
6.6. Right documentationRight documentation
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General Principles cont.General Principles cont.
Follow the rights consistentlyFollow the rights consistently
Learn essential information about each drugLearn essential information about each drug
Interpret prescribers orders correctlyInterpret prescribers orders correctly Read labels for right medication andRead labels for right medication and
concentrationconcentration
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Drug AdministrationDrug Administration
Minimize the use of abbreviationsMinimize the use of abbreviations
Calculate dosages correctlyCalculate dosages correctly
Measure doses accuratelyMeasure doses accurately Use appropriate anatomic landmarks toUse appropriate anatomic landmarks to
identify sites of IM injections-followidentify sites of IM injections-follow
manufacturers recommendationsmanufacturers recommendations Verify client identityVerify client identity
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Legal ResponsibilitiesLegal Responsibilities
Nurse is legally responsible for safe and accurateNurse is legally responsible for safe and accurateadministration of medicationsadministration of medications
Nurse is expected to have sufficient drugNurse is expected to have sufficient drugknowledge to recognize and question erroneousknowledge to recognize and question erroneousordersorders
Unit dose wrappings of oral drugs should be left inUnit dose wrappings of oral drugs should be left inplace until the nurse is in the presence of the clientplace until the nurse is in the presence of the clientand ready to administer the medicationand ready to administer the medication
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Medication OrdersMedication Orders
Include the full name of the patientInclude the full name of the patient
Generic or trade name of the drugGeneric or trade name of the drug
The dose, the route and frequency ofThe dose, the route and frequency ofadministrationadministration
Date, time and signature of the prescriberDate, time and signature of the prescriber
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Common abbreviationsCommon abbreviations
POPO
IMIM
IVIV SLSL
Sub qSub q
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Drug DosagesDrug Dosages
cccc
gg
GrGr
gttgtt
mLmL
ozoz
TspTsp
tbsptbsp
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Routes of AdministrationRoutes of Administration
OralOral
Via GI tubeVia GI tube
Parenteral-IM, IV and sub qParenteral-IM, IV and sub q TopicalTopical
Rectal, ophthalmicRectal, ophthalmic
OticOtic vaginalvaginal
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Sites for injectionsSites for injections
Sub q-abdomen, thighs, back and upperSub q-abdomen, thighs, back and upper
armsarms
IM-deltoid, dorsogluteal, ventrogluteal andIM-deltoid, dorsogluteal, ventrogluteal and
vastus lateralis musclesvastus lateralis muscles
IV-antecubital, hands, arms, external jugularIV-antecubital, hands, arms, external jugular
Others: intradermal, intra-articular, intra-Others: intradermal, intra-articular, intra-arterial and intrathecalarterial and intrathecal
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EquivalentsEquivalents
MetricMetric
ApothecaryApothecary
HouseholdHousehold (see p. 37)(see p. 37)
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Drug administration cardinal rulesDrug administration cardinal rules
Wash hands before giving medsWash hands before giving meds
Read MAR carefully. If ever in doubt, checkRead MAR carefully. If ever in doubt, check
the original orderthe original order
NeverNevergive medications you are uncertain ofgive medications you are uncertain of
unless you have looked them up or haveunless you have looked them up or have
consulted with pharmacyconsulted with pharmacy
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Drug Administration Cardinal RulesDrug Administration Cardinal Rules
NeverNevergive more than 3cc per IM injectiongive more than 3cc per IM injection
Wear gloves with all injectionsWear gloves with all injections
For sub q injections, use 25G, 5/8 needlesFor sub q injections, use 25G, 5/8 needles Do not give oral meds if patient is vomiting,Do not give oral meds if patient is vomiting,
sedated, NPO or is unconscioussedated, NPO or is unconscious
Follow narcotic protocol for signing out ofFollow narcotic protocol for signing out ofnarcoticsnarcotics
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Nursing Process in Drug TherapyNursing Process in Drug Therapy
Is a systematic way of gathering and usingIs a systematic way of gathering and using
information to plan and provideinformation to plan and provide
individualized client care and to evaluate theindividualized client care and to evaluate the
outcomes of careoutcomes of care
Five steps of the nursing process are:Five steps of the nursing process are:
assessment, nursing diagnosis, planning,assessment, nursing diagnosis, planning,
interventions and evaluationinterventions and evaluation
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General Principles of Drug TherapyGeneral Principles of Drug Therapy
Expected benefits should outweigh potentialExpected benefits should outweigh potential
adverse effectsadverse effects
Drug therapy should be individualizedDrug therapy should be individualized
Drug effects on quality of life should beDrug effects on quality of life should be
considered in designing a drug therapyconsidered in designing a drug therapy
regimentregiment
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Drug selection and dosageDrug selection and dosage
Use as few drugs as possibleUse as few drugs as possible
Fixed dose combinations increaseFixed dose combinations increasecompliancecompliance
Lowest dose with therapeutic effectLowest dose with therapeutic effect
Follow guidelines but dosages must beFollow guidelines but dosages must beindividualizedindividualized
Drugs with long half-lives may requireDrugs with long half-lives may requireloading doses then titrated lowerloading doses then titrated lowermaintenance dosesmaintenance doses
D Th i i l l tiD Th i i l l ti
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Drug Therapy in special populations-Drug Therapy in special populations-
pediatricspediatrics
Pediatrics-all aspects must be guided by thePediatrics-all aspects must be guided by the
childs age, weight and level of growth andchilds age, weight and level of growth and
developmentdevelopment
Safe therapeutic ranges are less well-Safe therapeutic ranges are less well-
defineddefined
Choice of drug is restricted because manyChoice of drug is restricted because many
drugs used in adults have not beendrugs used in adults have not been
sufficiently investigatedsufficiently investigated
P di t i h i l i h t i tiP di t i h i l i h t i ti
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Pediatric physiologic characteristicsPediatric physiologic characteristics
affecting pharmacokineticsaffecting pharmacokinetics
Thin, permeable skin increased absorptionThin, permeable skin increased absorption
of topicalsof topicals
Immature blood-brain barrierincreasedImmature blood-brain barrierincreased
distribution into the CNS until age 2distribution into the CNS until age 2
Altered protein binding until age 1Altered protein binding until age 1
Decreased activity of metabolizing enzymesDecreased activity of metabolizing enzymesin infants, increased in childrenin infants, increased in children
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Pediatric physiologic effectsPediatric physiologic effects
Increased percentage of body waterIncreased percentage of body water
Decreased GFR until one year of ageDecreased GFR until one year of age
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PediatricsPediatrics
Oral route for meds is preferableOral route for meds is preferable
For injections, may wish to use EMLAFor injections, may wish to use EMLA
(eutectic mixture of lidocaine and prilocaine,(eutectic mixture of lidocaine and prilocaine,
local anesthetics)local anesthetics)
Site selection for injectionsinfants, useSite selection for injectionsinfants, use
thigh muscles; older than 18 months of age,thigh muscles; older than 18 months of age,
use deltoid; older than 3, use ventroglutealuse deltoid; older than 3, use ventrogluteal
musclemuscle
Drug Therapy in Older AdultsDrug Therapy in Older Adults
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Drug Therapy in Older Adultsg py
Physiologic characteristics andPhysiologic characteristics and
pharmacokinetic impactpharmacokinetic impact Decreased GI motilityslower absorptionDecreased GI motilityslower absorption
Decreased cardiac outputslowerDecreased cardiac outputslower
absorption from site of administration,absorption from site of administration,decreased distribution to sites of action indecreased distribution to sites of action in
tissuestissues
Decreased blood flow to liver and kidneys-Decreased blood flow to liver and kidneys-delayed metabolism and excretiondelayed metabolism and excretion
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Drug Therapy in Older AdultsDrug Therapy in Older Adults
Decreased total body water and lean bodyDecreased total body water and lean body
mass-fat soluble meds stay with patientmass-fat soluble meds stay with patient
longer, water soluble drugs are distributed inlonger, water soluble drugs are distributed in
smaller area, greater risk for toxicitysmaller area, greater risk for toxicity
Decreased blood flow to liver-slowedDecreased blood flow to liver-slowed
metabolism and detox of drugsmetabolism and detox of drugs
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Drug Therapy in Older AdultsDrug Therapy in Older Adults
Decreased albumin-decreased availability ofDecreased albumin-decreased availability of
protein for binding and transporting. Willprotein for binding and transporting. Will
also have higher concentration of free activealso have higher concentration of free active
drug.drug.
Decreased blood flow to kidneysimpairedDecreased blood flow to kidneysimpaired
drug excretion, potential toxicitydrug excretion, potential toxicity
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Older AdultsOlder Adults
Renal ImpairmentRenal Impairment
Know baseline renal functionKnow baseline renal function
Tailor dosagesTailor dosages
Avoid nephrotoxic medicationsAvoid nephrotoxic medications Be aware of need for additional dosing ifBe aware of need for additional dosing if
patient is receiving renal replacementpatient is receiving renal replacement
therapytherapy
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Hepatic ImpairmentHepatic Impairment
Those with cirrhosis, hepatitis, receivingThose with cirrhosis, hepatitis, receiving
hepatotoxic drugs, have heart failure, arehepatotoxic drugs, have heart failure, are
undergoing major surgery or have had trauma areundergoing major surgery or have had trauma are
at higher risk for toxicities r/t medicationsat higher risk for toxicities r/t medications Know drug effects on hepatic functionKnow drug effects on hepatic function
Reduce dosages on medications that areReduce dosages on medications that are
extensively metabolized by the liver such as:extensively metabolized by the liver such as:
cimetidine, phenytoin, ranitidine, theophyllinecimetidine, phenytoin, ranitidine, theophylline
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Critical IllnessesCritical Illnesses
Be aware that all medications may haveBe aware that all medications may have
variable effects in this scenariovariable effects in this scenario
Know the actions, usual dosages and sideKnow the actions, usual dosages and side
effects of medicationseffects of medications
Closely monitor renal and liver function testsClosely monitor renal and liver function tests
Monitor serum protein and albumin levelsMonitor serum protein and albumin levels
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Older AdultsOlder Adults
Critical IllnessCritical Illness
Most drugs will be given IV-for this reason,Most drugs will be given IV-for this reason,
medications may have faster onsetmedications may have faster onset
Many factors may interfere with drug effectsMany factors may interfere with drug effects
if given orallyif given orally
Considerations when giving medications viaConsiderations when giving medications via
feeding tubefeeding tube
Appropriate scheduling very importantAppropriate scheduling very important
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Drug Therapy in Home CareDrug Therapy in Home Care
On patients turfOn patients turf
Schedule visit at convenient time for patientSchedule visit at convenient time for patient
and caregiverand caregiver
Assess patients ability to perform self-careAssess patients ability to perform self-care
Assess patients understanding and attitudeAssess patients understanding and attitude
regarding medication regimenregarding medication regimen Inquire if patient is taking any herbalInquire if patient is taking any herbal
preparationspreparations
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Drug Therapy in Home CareDrug Therapy in Home Care
Inquire if patient is taking any OTC medsInquire if patient is taking any OTC meds
Assess environment for safetyAssess environment for safety
Educate patient and caregiver indication,Educate patient and caregiver indication,proper administration and side effects ofproper administration and side effects of
administered medicationsadministered medications
Between visits, maintain contact with patientBetween visits, maintain contact with patientto monitor progress and serve as a resourceto monitor progress and serve as a resource
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Herbal and Dietary SupplementsHerbal and Dietary Supplements
Black cohosh-used to relieve menopausalBlack cohosh-used to relieve menopausal
s/ss/s
Capsaicin-post-herpetic neuralgiaCapsaicin-post-herpetic neuralgia
Echinacea-anti-infective, for common coldEchinacea-anti-infective, for common cold
Gingernausea. Not for morning sickness.Gingernausea. Not for morning sickness.
Garlic-cholesterol loweringGarlic-cholesterol lowering
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Herbal and Dietary supplementsHerbal and Dietary supplements
Feverfew-for migraines, menstrualFeverfew-for migraines, menstrual
complaints. Can cause withdrawal s/s.complaints. Can cause withdrawal s/s.
Ginseng-increase stamina, endurance andGinseng-increase stamina, endurance and
mental acuity. Can affect bleeding time, BP,mental acuity. Can affect bleeding time, BP,
increase hypoglycemia. No longer than 3increase hypoglycemia. No longer than 3
weeks use with Siberian ginseng.weeks use with Siberian ginseng.
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QuestionsQuestions