Pharmacology Week 1
n n
Principles of Pharmacology
n n n
Pharmacokinetics = the study of drug absorption, distribution, metabolism and excretion (AD
n n n n n n n n n n
ME)
Whatnthenbodyndoesntonandrug n
FDAnrequiresnthatnstudiesnbendonenfornallncompounds
INDnapplication=nallnstudiesnandndesignnofnthenparticular ndrug n
Clinicalnphasenone…nsafetynofnthendrug nevaluates,nthenpharmacokineticsn
ClinicalnPhasen2…nefficacynofnthencompound,nfinding ntonoptimalndosen
ClinicalnPhasen3…nthousandsnofnvolunteer’snspecificndata,nlabeling ndatan
Drug nisnapproved:npostnmarketnadverseneffects,nmonitoring nn
Wenhavennonideanwhatnisninnthensupplementsnpeoplenputninntheir nbodyn
Don’tntakentoonmanynvitaminsn
Supplementnmanufacturersnarennotnheldntonthensamenstandardnasnpharmaceutical ncompaniesn
NotnallnarenFDAnapprovedn
n Alternativen medicinen isn notn alwaysn then answer
Absorption
n hasn ton happenn son thatn then drug n goesn inton then bloodn stream n
IVnthatngonintonthenbloodndonnotnhavenabsorptionn
Transdermal ngonthrunthenskinnintonthenbloodstreamn
Sublingualnunder nthentonguenn
Oralnintonstomachnabsorbednthroughnthenduodenum
Inhalendrugsnn
Distribution
Howndoesnitnknownwherentongon
Hownthendrug nandnornmetabolitenandngetsnwherenitnneedsntonben
Goesnallnthroughnthenbody…isnnotndirectedntonancertainnspotnn
Metabolismn
Hownthendrug ngetsntransformedninnthenbodyneither nintonanninactivencomponentnornactive
EX:nBetanblockersn(slowsnheartnratenlowersnthenBP….nItndoesnthisninnitsnactivenstate)
Aminophylline(prondrug ngetsnabsorbednintonbodynandngetsnconvertednintonsomething nelse…itnhasn
nontrueneffectnonnthenbody)nandnthennconvertsnintoncaffeinen(activenmetabolite)n
Donenbynthenliver n
Excretion
Hownthendrug nandnmetabolitenareneliminatednfromnthenbodyn
Breathing noutngarlicnfornexamplen
,Anlotnofnitngetsnbreathednoutnthroughnthenlungsn(alcoholnfornexample…nbreathalyzer…nmeasuring n
metabolites)
Onset Peak and Duration
n n n
Whennwenadminister nandrug nitngetsnabsorbednandnreachesnminimalneffectivenconcentration…nacti
onnofnthendrug n
Certainnamountnneedsntonbenabsorbednbeforenitnacts
Peaknlevelnisnwherentherenisnthengreatestnconcentrationnofnthendrug nandnthenpeakneffect…nitnisnthen
highestnbloodnconcentrationn
Thannthenbodyndistributesnitn(thenconcentrationndecreasesninnthenblood)
Thenneliminatesn(minimalneffectivenconcentration)
MostnPOndrugsntakesn30nminutesn
Durationnofnactionn(hownlong nthendrug nlasts)n
Onsetnofnactionnisnthenabsorption
Half-life n
(thentimenrequirednfor n½nofnthendrug ntonbenremovednfromnthenbody)
Othernhalfnlifen
(elimination,nplasmanandntherapeutic)
Renwatch nthisnpart nofnthenvideon
Whennwengivenandrug…nwenwillnstartnatn0nandngiventhenfirstndosenwhichnfollowsnthenpatternn
Dosing nintervals…nthenmeannconcentrationnincreasesn
After n4norn5nhalf-livesnwenarennownatnsteadynstaten
SteadynstatenmeansnthatnwhennIngiventhennextndosenofnplasmanitnwillnnotnchangenthenplasmanconc
entration…nifnyounhavenbeennonnandrug nfornanlong nperiodnofntimenyounarenonnsteadynstate…nitnwon’
,tnreallynchangenthenconcentration…nandnifnInamnlatengiving nthenconcentrationnitnwon’tnreallynmatte
rn
Pharmacodynamics (the study of the biochemical and physiologic interactions of drugs at
n n n n n n n n n n n
ntheirnsitenofnactivity)
Naturalnresponse=Naturalnchemicalnhitsnreceptor nsitenandnitngivesnyounannormalnresponsen
Mimickednresponse=Agonistsndrug nsimulatesnthennaturalnchemicalnatnthenreceptor nsiten(adrenalin
enmimicsnSNS)
Blockednresponse=n(hitting nreceptor nsitenandnblocking nit)
Types of therapy
n n
• Acutentherapy
• Maintenancentherapyn(IVnfluid)nmaintainnnormalnphysiologicnresponsesn
• SupplementalnTherapyn(Oxygen)
• PalliativenTherapyn(minimizensuffering)nchemonfornexamplen
• SupportivenTherapyn(whennpatientsnneednmorenofnsomething nlikenPPNnornTPN…nsupportin
g nthengoalnofngiving nnutritionntonthenpatient
• Prophylaxisnandnempiricntherapy
o Prophylacticntherapyn(giving nitnbeforenitnhappensntonpreventnit)
, o Empiricntherapyn(giving nitnbasednonnthenevidence)n
• Directiventherapyn(taking nthenorganismnandnexposing nitntonthendrugs…whichndrug nandnho
wnlong nwengivenit)ntaking nbloodnandnseeing nthenorganismn
Monitoring
TherapeuticnIndexn
Drug nconcentration
Patientncondition…ngiventhemnanbetanblocker nmonitor nheartnratenandnBP
Tolerancenandndependence…nopioidncrisis
Interactions…ntwonmedicinesnarennotncompatible…nmedicinentonmedicine
Adverse drug events… unexpected or undesired
n n n n n n
Allergicn
Idiosyncraticnunexpectednnotnannallergy...nallergicntonwater ngetsnhivesn
Teratogenicityn(effectnofnfetus)
Mutagenicityn(mutationnonngenes)
Carcinogenicityn(causesncancer)nnn
Rights of medication Administration
n n n n
Rightndrug
Rightndosen
Rightntime
Rightnrouten
Rightnpatientn
ANDnIsnthenpatientnallergic???
Lifespan considerations
n n
Neonatalnandnpedsn(theynarennotnfullyndeveloped)n
Pregnancyn(2npatients)n
Elderlyn(manynphysiological nchanges)
Cultural considerations
n n
Beliefsnaboutnhealthnandnwellness,nrolenofnthenfamily,nbiological nvariationsnandnalternativenhealin
gn
Exampleneffectsnofnvisiting nhoursnandnitsnimportancentonthenpatient
n n
Principles of Pharmacology
n n n
Pharmacokinetics = the study of drug absorption, distribution, metabolism and excretion (AD
n n n n n n n n n n
ME)
Whatnthenbodyndoesntonandrug n
FDAnrequiresnthatnstudiesnbendonenfornallncompounds
INDnapplication=nallnstudiesnandndesignnofnthenparticular ndrug n
Clinicalnphasenone…nsafetynofnthendrug nevaluates,nthenpharmacokineticsn
ClinicalnPhasen2…nefficacynofnthencompound,nfinding ntonoptimalndosen
ClinicalnPhasen3…nthousandsnofnvolunteer’snspecificndata,nlabeling ndatan
Drug nisnapproved:npostnmarketnadverseneffects,nmonitoring nn
Wenhavennonideanwhatnisninnthensupplementsnpeoplenputninntheir nbodyn
Don’tntakentoonmanynvitaminsn
Supplementnmanufacturersnarennotnheldntonthensamenstandardnasnpharmaceutical ncompaniesn
NotnallnarenFDAnapprovedn
n Alternativen medicinen isn notn alwaysn then answer
Absorption
n hasn ton happenn son thatn then drug n goesn inton then bloodn stream n
IVnthatngonintonthenbloodndonnotnhavenabsorptionn
Transdermal ngonthrunthenskinnintonthenbloodstreamn
Sublingualnunder nthentonguenn
Oralnintonstomachnabsorbednthroughnthenduodenum
Inhalendrugsnn
Distribution
Howndoesnitnknownwherentongon
Hownthendrug nandnornmetabolitenandngetsnwherenitnneedsntonben
Goesnallnthroughnthenbody…isnnotndirectedntonancertainnspotnn
Metabolismn
Hownthendrug ngetsntransformedninnthenbodyneither nintonanninactivencomponentnornactive
EX:nBetanblockersn(slowsnheartnratenlowersnthenBP….nItndoesnthisninnitsnactivenstate)
Aminophylline(prondrug ngetsnabsorbednintonbodynandngetsnconvertednintonsomething nelse…itnhasn
nontrueneffectnonnthenbody)nandnthennconvertsnintoncaffeinen(activenmetabolite)n
Donenbynthenliver n
Excretion
Hownthendrug nandnmetabolitenareneliminatednfromnthenbodyn
Breathing noutngarlicnfornexamplen
,Anlotnofnitngetsnbreathednoutnthroughnthenlungsn(alcoholnfornexample…nbreathalyzer…nmeasuring n
metabolites)
Onset Peak and Duration
n n n
Whennwenadminister nandrug nitngetsnabsorbednandnreachesnminimalneffectivenconcentration…nacti
onnofnthendrug n
Certainnamountnneedsntonbenabsorbednbeforenitnacts
Peaknlevelnisnwherentherenisnthengreatestnconcentrationnofnthendrug nandnthenpeakneffect…nitnisnthen
highestnbloodnconcentrationn
Thannthenbodyndistributesnitn(thenconcentrationndecreasesninnthenblood)
Thenneliminatesn(minimalneffectivenconcentration)
MostnPOndrugsntakesn30nminutesn
Durationnofnactionn(hownlong nthendrug nlasts)n
Onsetnofnactionnisnthenabsorption
Half-life n
(thentimenrequirednfor n½nofnthendrug ntonbenremovednfromnthenbody)
Othernhalfnlifen
(elimination,nplasmanandntherapeutic)
Renwatch nthisnpart nofnthenvideon
Whennwengivenandrug…nwenwillnstartnatn0nandngiventhenfirstndosenwhichnfollowsnthenpatternn
Dosing nintervals…nthenmeannconcentrationnincreasesn
After n4norn5nhalf-livesnwenarennownatnsteadynstaten
SteadynstatenmeansnthatnwhennIngiventhennextndosenofnplasmanitnwillnnotnchangenthenplasmanconc
entration…nifnyounhavenbeennonnandrug nfornanlong nperiodnofntimenyounarenonnsteadynstate…nitnwon’
,tnreallynchangenthenconcentration…nandnifnInamnlatengiving nthenconcentrationnitnwon’tnreallynmatte
rn
Pharmacodynamics (the study of the biochemical and physiologic interactions of drugs at
n n n n n n n n n n n
ntheirnsitenofnactivity)
Naturalnresponse=Naturalnchemicalnhitsnreceptor nsitenandnitngivesnyounannormalnresponsen
Mimickednresponse=Agonistsndrug nsimulatesnthennaturalnchemicalnatnthenreceptor nsiten(adrenalin
enmimicsnSNS)
Blockednresponse=n(hitting nreceptor nsitenandnblocking nit)
Types of therapy
n n
• Acutentherapy
• Maintenancentherapyn(IVnfluid)nmaintainnnormalnphysiologicnresponsesn
• SupplementalnTherapyn(Oxygen)
• PalliativenTherapyn(minimizensuffering)nchemonfornexamplen
• SupportivenTherapyn(whennpatientsnneednmorenofnsomething nlikenPPNnornTPN…nsupportin
g nthengoalnofngiving nnutritionntonthenpatient
• Prophylaxisnandnempiricntherapy
o Prophylacticntherapyn(giving nitnbeforenitnhappensntonpreventnit)
, o Empiricntherapyn(giving nitnbasednonnthenevidence)n
• Directiventherapyn(taking nthenorganismnandnexposing nitntonthendrugs…whichndrug nandnho
wnlong nwengivenit)ntaking nbloodnandnseeing nthenorganismn
Monitoring
TherapeuticnIndexn
Drug nconcentration
Patientncondition…ngiventhemnanbetanblocker nmonitor nheartnratenandnBP
Tolerancenandndependence…nopioidncrisis
Interactions…ntwonmedicinesnarennotncompatible…nmedicinentonmedicine
Adverse drug events… unexpected or undesired
n n n n n n
Allergicn
Idiosyncraticnunexpectednnotnannallergy...nallergicntonwater ngetsnhivesn
Teratogenicityn(effectnofnfetus)
Mutagenicityn(mutationnonngenes)
Carcinogenicityn(causesncancer)nnn
Rights of medication Administration
n n n n
Rightndrug
Rightndosen
Rightntime
Rightnrouten
Rightnpatientn
ANDnIsnthenpatientnallergic???
Lifespan considerations
n n
Neonatalnandnpedsn(theynarennotnfullyndeveloped)n
Pregnancyn(2npatients)n
Elderlyn(manynphysiological nchanges)
Cultural considerations
n n
Beliefsnaboutnhealthnandnwellness,nrolenofnthenfamily,nbiological nvariationsnandnalternativenhealin
gn
Exampleneffectsnofnvisiting nhoursnandnitsnimportancentonthenpatient
