Pharmacology Principles Flashcards
Pharmacotherapy
Selecting right DRUG, in right DOSE to interact with right TARGET to bring about desired therapeutic effects (Prevention, Diagnosis, Treatment, Cure)
Onset of effect
Time to reach MEC
Duration of action
Time drug is above MEC
Therapeutic Window (Therapeutic Index)
Difference in Plasma concentration between desired and adverse response
Goal of multiple dosage pharmacothearpy
reach and maintain steady state plasma concentration of drug within therapeutic window to get desired therapeutic response with minimum toxicity
Steady state
rate of drug administration = rate of elimination
MEC
Minimum effective concentration; determined for therapeutic and adverse responses
Steady State Cp
average plasma concentration when steady state reached
fluctuations in steady state
related to number of half lives in dosing interval. Concentration of drug will rise after drug admin and fall at certain rate until next dose administered
Dosage regimen
ensures steady state maintained within therapeutic window. Select DRUG/DOSE, ROUTE, FREQUENCY(INTERVAL), DURATION
Common drug targets
membrane/intracellular receptors, enzyme in biosynthetic pathway, membrane transport protein
Pharmacokinetics
What does body do to drug – Absorption, Distribution, Metabolism, Elimination
Absorption
drug movement from site of administration to bloodstream
Distribution
Movement from blood stream to tissues where it accesses target
Elimination
elimination of drug after administration by both metabolism and excretion