GIT Diseases: effect on absorption Flashcards
Which one out of pharmacokinetics or pharmacodynamic changes the unbound conc response curve and pharmacokinetic parameters of Ka,F,V,CLr,CLh?
kinetic - no change to curve only parameters
dynamic - change to curve not parameters
How does altered gastric pH change absorption?
compounds which create an environment with specific pH affect solubility and permeability of co- administered drugs
How does chelation affect absorption?
drug forms insoluble complex in GIT by chelation ( formation of ring structure between a metal ion & organic molecule)
How does adsorption affect absorption?
process of ion binding or hydrogen binding, drugs which are adsorbents
How does changes in gastric emptying & intestinal motility affect absorption?
primary location of drug absorption is small intestines so eating fatty or lipid based formulation will result in delayed gastric emptying
How can intestinal blood flow be modulated?
by vasoactive agents, constrict or dilate blood vessels)
How does effects on P-glycoprotein alter activity of epithelial transporters?
P-glyco broad substrate specificity, therefore inhibiting or inducing the activity can lead to drug alterations
How does the elimination of drugs occur?
by excretion & metabolism
What are the four common metabolic reactions?
oxidation, reduction, hydrolysis and conjugation
What are phase 1 reactions and which processes take part in this?
occur first - oxidation, reduction and hydrolysis
What are phase 2 reactions and which processes take part in this?
occur second - conjugation
Where is CYP3A usually found?
intestinal wall & liver
