Drug Excretion Flashcards
What organ excretes drugs
Kidneys
Where is the drug absorbed (excretion)
Distal tubule
What drugs are absorbed through proximal tubule for excretion
Dioxin and penicillin
What happens if rental function is impaired
Drugs that are primarily excreted as active metabolites will be eliminated slowly
What happens when kidney isn’t working
Drugs stay longer in the system leading to increased side effects
What consequence does it have if normal dosage isn’t decreased
Plasma level of the drug will rise and produce toxic effects
What other ways are drugs exctpreted
Lungs or bile
Example of drug excreted by lung
Nitrous oxide (anaesthetic)
What is therapeutic dose range
The interval between the lowest dose that produces no desired effect and the highest dose that causes toxicity
What does plasma level do do drug absorption
-Increases drug absorption
- fast plasma level = fast absorption
As drug absorption decreases what increases
Distribution, excretion and metabolism increases
What happens when absorption reaches its peak
It balances with elimination
Why does absorption fall when it balances with elimination
Elimination is faster than absorption.
What happens to the therapeutic range as dose increase and why
The therapeutic range increases as more cell receptors are occupied
What happens when receptors of target organs are occupied by drug
The drug produces a maximal effect
