Renal excretion Flashcards
what happens if the drug is retained in plasma?
it reaches the organs of elimination more quickly so it shortens the duration of action
what happens if the drug in plasma is highly bound to proteins
it cannot be filtered and removed from the kidney effectively
what happens to duration of action if the drug is distributed through tissue?
takes longer to reach the organs of elimination because it has sequestered from the circulation, which can extend the half life
how does a drug retained in tissue reduce clinical response?
less of it can reach the target
what is drug metabolism?
transformation of a drug into a form that is readily excreted by modification of its molecular properties (lowers lipophillicity to get rid of drug - needs to be water soluble)
what is drug excretion?
removal of modified species from the body, primarily via the kidney for water soluble species
how would you know if drugs and their metabolites was present in urine?
- macro level - colour, smell
- micro level - analytical spectrometry
what is xenobiotic?
sees something as toxic and tried to get rid of it
how to increase hydrophilicity?
introducing polar groups or removing lipophilic groups
how do transporters work to aid renal excretion?
involved in taking things out the nephron back into the blood stream to be reabsorbed
they recognise unfiltered drugs and remove it to the bloodstream based on charge (cationic and anionic)
how does log D affect reabsorption?
if log D is + it was be reabsorbed
if log D is - less of the drug is reabsorbed = more excretion
what are factors effecting renal excretion?
Plasma protein binding
Age
Renal function
Blood flow
