Pharmacology Flashcards
What is pharmacology
Study of drug action on the body
What is pharmacokinetics
The study of what the body does to a drug
What is pharmacodynamics
Physiological effects of a drug on the body
What does ADME mean in pharmacokinetics
Absorption
Distribution
Metabolism
Excretion
If a drug is given orally, where does it go
GI tract
What happens when a drug is absorbed by the GI tract
Goes to the liver where some drugs are broken down
How can elimination happen
Broken down by liver
Excreted by kidneys
Excreted via lungs
Where does pharmacological action happen
Circulation tissue space
What is absorption
Rate and extent at which a drug leaves its site of administration and enters the circulatory system
What can impede the efficacy of a drug
Route of administration e.g. orally or rectally
What can enhance or impair the rate of absorption
Presence of food
What happens when the GI tract is compromised
A parenteral route must be considered
Why does location of drug administration need to be considered
Tissue perfusion will also impact on absorption
What is first pass effect
When a drug has been absorbed into circulation it is transported to the liver via hepatic portal system where it is metabolised
Why do we have to reduce the amount of active drug being distributed within the body
Because some drugs undergo extensive hepatic metabolism
What is produced by first pass effect
Drug and metabolites
How can first pass effect be avoided
Using parenteral route which bypasses this process and provides body with a more accurate dosage
Once a drug has been metabolised by the liver, where does it go
Enters the systemic circulation and travels in the plasma to its site of action
What happens once a drug has reached the desired site of action
It leave the plasma and enters interstitial fluid then the cells and combines cellular receptors to create an action
What affects drug distribution
Drug formulation
Blood flow to that area
Binding/unbinding of the drug to plasma proteins
Presence of anatomic barriers
What are fat loving drugs
Lipophilic
What are water loving drugs
Hydrophilic
Which route of administration is best for hydrophilic drugs
IV, IM as they enter the extra cellular fluid
Which route of administration is best for lipophilic drugs
Orally or SC as needs rap diffuse through a cell membrane