給藥1參考資料

給藥

(一)Medications(one)

Amedicationisasubstanceadministeredforthediagnosis,cure,treatment,mitigation(relief),orpreventionofdisease.Inthehealthcarecontext,thewordsmedicationanddrugaregenerallyusedinterchangeably.Thetermdrugalsohastheconnotationofanillicitlyobtainedsubstancesuchasheroin,cocaine,oramphetamines.IntheUnitedStatesandCanada,medicationsareusuallydispensedontheorderofphysiciansanddentists.InsomeUSstates,speciallyqualifiednurse-practitionersandphysician’sassistantsmayprescribedrugs.Thewrittendirectionforthepreparationandadministrationofadrugiscalledaprescription.Onedrugcanhaveasmanyasfourkindsofnames:itsgenericname,officialname,chemicalname,andtrademarkorbrandname.Thegenericnameisgivenbeforeadrugbecomesofficial.Theofficialnameisthenameunderwhichitislistedinoneoftheofficialpublications(eg,theUnitedStatesPharmacopeia).

Thechemicalnameisthenamebywhichachemistknowsit;thisnamedescribestheconstituentsofthedrugprecisely.Thetrademark,orbrandname,isthenamegivenbythedrugmanufacturer.Becauseonedrugmaybemanufacturedbyseveralcompanies,itcanhaveseveraltradenames.Medicationsareoftenavailableinavarietyofforms.Theyareaerosolsprayorfoam,aqueoussolution,aqueoussuspension,caplet,capsule,cream,elixir,extract,gelorjelly,liniment,lotion,lozenge(troche),ointment(salve,unction),paste,pill,powder,suppository,syrup,tablet,tincture,transdermalpatch.

Pharmacologyisthestudyoftheeffectofdrugsonlivingorganisms.Pharmacyistheartofpreparing,compounding,anddispensingdrugs.Thewordalsoreferstotheplacewheredrugsarepreparedanddispensed.Drugsarepreparedbyapharmacist,apersonlicensedtoprepareanddispensedrugsandtomakeupprescriptions.Aclinicalpharmacistisaspecialistwhooftenguidesthephysicianinprescribingdrugs.Apharmacytechnicianisamemberofthehealthteamwhoinsomestatesadministersdrugstoclients.DRUGSTANDARDS

?Drugsmayhavenatural(eg,plant,mineral,andanimal)sourcesortheymaybesynthesizedinthelaboratory.Forexample,digitalisandopiumareplantderived,ironandsodiumchlorideareminerals,insulinandvaccineshaveanimalorhumansources,andthesulfonamidesandpropoxyphenehydrochloride(theanalgesicDarvon)aretheproductsoflaboratorysynthesis.?Drugsvaryinstrengthandactivity.Drugsderivedfromplants,forexample,varyinstrengthaccordingtotheageoftheplant,thevariety,theplaceinwhichitisgrown,andthemethodbywhichitispreserved.Drugsmustbepureandofuniformstrengthifdrugdosagesaretobepredictableintheireffect.?Drugstandardshavethereforebeendevelopedtoensureuniformquality.IntheUnitedStates,officialdrugsarethosesodesignatedbytheFederalFood,Drug,andCosmeticAct.ThesedrugsareofficiallylistedintheUnitedStatesPharmacopeia(USP)anddescribedaccordingtotheirsource,physicalandchemicalproperties,testsforpurityandidentity,methodofstorage,assay,category,andnormaldosages.第一課件網(wǎng)

?APharmacopoeia(alsospelledpharmacopeia)isabookcontainingalistofproductsusedinmedicine,withdescriptionsoftheproduct,chemicaltestsfordeterminingidentityandpurity,andformulasandprescriptions.TheUnitedStates’NationalFormularylistsdrugsandtheirtherapeuticvalueandcanincludedrugsthatmaystillbeusedbutnotlistedintheUSP.?Pharmacopoeiasandformulariesareinvaluablereferencesourcesfornursesandnursingstudents.Nursesnotonlyadministerthousandsofmedicationsbutalsoareresponsibleforassessingtheireffectivenessandrecognizingunfavorablereactionstodrugs.Sinceitisimpossibletocommittomemoryallpertinentinformationaboutaverylargenumberofdrugs,nursesmusthaveareliablereferencereadilyavailable.LEGALASPECTSOFDRUGADMINISTRATION

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TheadministrationofdrugsinboththeUnitedStatesandCanadaiscontrolledbylaw.

Nursesneedto(a)knowhownursingpracticeactsintheirareasdefineandlimittheirfunctionsand(b)beabletorecognizethelimitsoftheirownknowledgeandskill.Tofunctionbeyondthelimitsofnursingpracticeactsorone’sabilityistoendangerclients’livesandleaveoneselfopentomalpracticesuits.?Underthelaw,nursesareresponsiblefortheirownactionsregardlessofwhetherthereisawrittenorder.Ifaphysicianwritesanincorrectorder(eg,Demerol500mginsteadofDemerol50mg),anursewhoadministersthewrittenincorrectdosageisresponsiblefortheerror.Therefore,nursesshouldquestionanyorderthatappearsunreasonableandrefusetogivethemedicationuntiltheorderisclarified.?Anotheraspectofnursingpracticegovernedbylawistheuseofcontrolledsubstances.Inhospitals,controlledsubstancesarekeptinalockeddrawer,cupboard,medicationcart,orcomputer-controlleddispensingsystem.Agencieshavespecialformsforrecordingtheuseofcontrolledsubstances.?Theinformationrequiredusuallyincludesthenameoftheclient,thedateandtimeofadministration,thenameofthedrug,thedosage,andthesignatureofthepersonwhopreparedandgavethedrug.Thenameofthephysicianwhoorderedthedrugmayalsobepartoftherecord.

?Includedontherecordarethecontrolledsubstanceswastedduringpreparation.Inmostagencies,countsofcontrolledsubstancesaretakenattheendofeachshift.Thecounttotalshouldtallywiththetotalattheendofthelastshiftminusthenumberused.Ifthetotalsdonottally,thediscrepancymustbereportedimmediately.Infacilitiesthatuseacomputerizeddispensingsystem,manualcountsarenotrequired,becausethedispensingsystemrunsacontinuouscount;however,discrepanciesmustbeaccountedfor.EFFECTSOFDRUGS

1.Thetherapeuticeffectofadrug,alsoreferredtoasthedesiredeffect,istheprimaryeffectintended,thatis,thereasonthedrugisprescribed.Forexample,thetherapeuticeffectofmorphinesulfateisanalgesia,andthetherapeuticeffectofdiazepamisreliefofanxiety.Thekindsoftherapeuticactionsareasfollows:palliative,curative,supportive,substitutive,chemotherapeuticandrestorative.

2.Asideeffect,orsecondaryeffect,ofadrugisonethatisunintended.Sideeffectsareusuallypredictableandmaybeeitherharmlessorpotentiallyharmful.Forexample,digitalisincreasesthestrengthofmyocardialcontractions(desiredeffect),butitcanhavethesideeffectofinducingnauseaandvomiting.Somesideeffectsaretoleratedforthedrug’stherapeuticeffect;moreseveresideeffects,alsocalledadverseeffects,mayjustifythediscontinuationofadrug.3.Drugtoxicity(deleteriouseffectsofadrugonanorganismortissue)resultsfromoverdosage,ingestionofadrugintendedforexternaluse,andbuildupofthedruginthebloodbecauseofimpairedmetabolismorexcretion(cumulativeeffect).Sometoxiceffectsareapparentimmediately;somearenotapparentforweeksormonths.Fortunately,mostdrugtoxicityisavoidableifcarefulattentionispaidtodosageandmonitoringfortoxicity.Anexampleofatoxiceffectisrespiratorydepressionduetothecumulativeeffectofmorphinesulfateinthebody.4.Adrugallergyisanimmunologicreactiontoadrug.Whenaclientisfirstexposedtoaforeignsubstance(antigen),thebodymayreactbyproducingantibodies.Aclientcanreacttoadrugastoanantigenandthusdevelopsymptomsofanallergicreaction.?Allergicreactionscanbeeithermildorsevere.Amildreactionhasavarietyofsymptoms,whichareskinrashes,pruritus,angioedema,rhinitis,lacrimaltearing,nausea,vomiting,wheezinganddyspnea,diarrhea.Anallergicreactioncanoccuranytimefromafewminutesto2weeksaftertheadministrationofthedrug.第一課件網(wǎng)

?Asevereallergicreactionusuallyoccursimmediatelyaftertheadministrationofthedrug;itiscalledananaphylactic

reaction.Thisresponsecanbefatalifthesymptomsarenotnoticedimmediatelyandtreatmentisnotobtainedpromptly.Theearliestsymptomsareacuteshortnessofbreath,acutehypotension,andtachycardia.

5.Drugtoleranceexistsinapersonwhohasunusuallylowphysiologicactivityinresponsetoadrugandwhorequiresincreasesinthedosagetomaintainagiventherapeuticeffect.Drugsthatcommonlyproducetoleranceareopiates,barbiturates,ethylalcohol,andtobacco.?Acumulative

effectistheincreasingresponsetorepeateddosesofadrugthatoccurswhentherateofadministrationexceedstherateofmetabolismorexcretion.Asaresult,theamountofthedrugbuildsupintheclient’sbodyunlessthedosageisadjusted.Toxicsymptomsmayoccur.?Anidiosyncratic

effectisunexpectedandindividual.Underresponseandoverresponsetoadrugmaybeidiosyncratic.Also,thedrugmayhaveacompletelydifferenteffectfromthenormaloneorcauseunpredictableandunexplainablesymptomsinaparticularclient.

6.Adruginteractionoccurswhentheadministrationofonedrugbefore,atthesametimeas,orafteranotherdrugalterstheeffectofoneorbothdrugs.

?Theeffectofoneorbothdrugsmaybeeitherincreased(potentiatingorsynergisticeffect)ordecreased(inhibitingeffect).?Druginteractionsmaybebeneficialorharmful.Forexample,probenecid,whichblockstheexcretionofpenicillin,canbegivenwithpenicillintoincreasebloodlevelsofthepenicillinforlongerperiods(potentiatingeffect).Twoanalgesics,suchasaspirinandcodeine,areoftengiventogetherbecausetogethertheyprovidegreaterpainrelief(additiveeffect).?Inaddition,certainfoodsmayinteractadverselywithamedication.SeeTable44-1.

7.Iatrogenicdisease(diseasecausedunintentionallybymedicaltherapy)canbeduetodrugtherapy.Hepatictoxicityresultinginbiliaryobstruction,renaldamage,andmalformationsofthefetusasaresultofspecificdrugstakenduringpregnancyareexamples.DRUGMISUSE

1.Drugmisuseistheimproperuseofcommonmedicationsinwaysthatleadtoacuteandchronictoxicity.Bothover-the-counterdrugsandprescriptiondrugsmaybemisused.Laxatives,antacids,vitamins,headacheremedies,andcoughandcoldmedicationsareoftenself-prescribedandoverused.Mostpeoplesuffernoharmfuleffectsfromthesedrugs,butsomepeopledo.Apersistentcoughmaygoundiagnoseduntiltheunderlyingproblembecomesseriousandadvanced.

2.Drugabuseisinappropriateintakeofasubstance,eithercontinuallyorperiodically.Bydefinition,druguseisabusivewhensocietyconsidersitabusive.Forexample,theintakeofalcoholatworkmaybeconsideredalcoholabuse,butintakeatasocialgatheringmaynot.Drugabusehastwomainfacets,drugdependenceandhabituation.

?Drugdependenceisaperson’srelianceonorneedtotakeadrugorsubstance.Thetwotypesofdependence,physiologicandpsych