Pharmacology Flashcards
What is pharmacokinetics?
The study of the movement of a drug in and out of the body
What is pharmacodynamics?
The study of drug effect and mechanism of action
What is pharmacogenetics?
The effect of genetic variability on pharmacokinetics and pharmacodynamics in an individual
What is bioavailability?
The fraction of a dose which makes its way into a body compartment.
What affects bioavailability?
The absorption of a drug
First pass metabolism
Where can first pass metabolism occur?
Gut lumen
Gut wall
Liver
What properties should a drug have to consider its protein binding interactions?
High protein binding
Low volume of distribution
Narrow therapeutic ratio
What can affect the tissue distribution of a drug?
Receptor sites in tissues Regional blood flow Lipid solubility Active transport Disease states Drug interactions
What can affect the cytochrome p450 enzyme system in the liver?
Age Alcohol consumption Drugs Smoking Liver disease Hepatic blood flow
Which drug properties make it important to monitor them?
Zero order kinetics Long half life Narrow therapeutic window Greater risk of drug-drug interactions Known toxic effects Monitoring therapeutic effects
Describe first order kinetics
Linear on a logarithmic scale
Rate of elimination is proportional to the drug level
Half life can be defined
Describe zero order kinetics
Non linear
Elimination is constant so the half life is impossible to be calculated
Dosing is less predictable
What part of the dosing regimen do you have to change in renal failure?
Maintenance dose
Give an example of a biguanide.
Metformin
Describe the action of metformin
Reduced hepatic glucose production
Increases glucose uptake and utilisation in skeletal muscle
Reduce carbohydrate absorption
Increase fatty acid oxidation
