Lecture 2: General Principles of Pharmacology Flashcards
The study of how the body absorbs, distributes, and eliminates the drug (what the body does to the drug)
Pharmacokinetics
The analysis of what the drug does to the body, including the mechanism by which the drug exerts its effect
Pharmacodynamics
What is toxicology
Stufy of the harmful effects of chemicals
Deals with the genetic basis for drug responses, especially variations in drug response from person to person
Pharmacogenetics
Releated to the dose that produces a given response in a specific amplitude
Potency
Is potency a maximal efficacy?
No, its the desired potency
A drug with a low dosage has more or less potency?
More - you need less of it achieve desired outcome
Drug A = 10 mg
Drug B = 100 mg
Drug A is more potent
TEST Do safer drugs have a higher or lower theraputic index?
Higher
Higher therapetic index = larger dose to reach toxic value (you need lots of the drug for it to become toxic)
Therapeutic index equation
Leathal dose / effective dose
the higher the # the safer it is
higher means it takes a larger dose to reach that toxic level
KNOW: Routes of drug administration affects how much gets to the target tissue (amount of bioaviability)
The extent to which the drug reaches the systemic circulation is
Bioavailability
We often use systemic circulation to asses if there is enough drug availble in the system to reach the optimal dose
affected by route of administration
Distribution of the drug to the body depends on: (4)
1) Tissue permability
2) Blood flow to that area
3) Binding to plasma proteins
4) Binding to subcellular components
Long term storage sites for drugs (4)
1) Adipose
2) Bones
3) Muscules
4) Organs
What organ detoxes?
Liver
What biotransformation and what organ does it?
Chemically altering the original compound so that it is no longer active
* aka drug metabolism
Liver does this
To a lesser extent: Lungs, kidneys, GI epithelium, and skin
What organ is the primary site for drug excretion?
Kidneys
Systemic or single organ’s ability to eliminate the drug
Clearance
NOTE: Older people have a lower clearance, meaning some drugs have the ability to stay there longer
* This is important for drugs that need to stay there to be maintained at a certain level
what is half life?
Amount of time required for 50% of the drug remianing in the body to be eliminated
* important because it could piggy back
Variations in drug response:
* Genetics
* Disease
* Drug interactions
* Age
* Diet
* gender
* Social determinants of health (are you not taking your medication because you’re trying to save money)
KNOW: grapefruit have a moleculat that stops CYP
CYP breaks down drugs
Take grapefruit juice is stop the breakdown of drugs = increase drug in system
* mostly heart medications
This also lowers BP
The amount of attraction between drug and receptors =
* releated to the drug amount that is required to bind to the unoccupied receptors
Drug affinity
If it affects only one type of cell of tissue and produces a specific physiological affect is is
drug selectivity
KNOW: Non selective drugs can bind all over the place while selective drugs have very limited binding places
What is an agonist
A drug that can bind to a receptor and initiate a change in a cells function
* Key that goes in and activates what its supposed to activate
What is an antagonist
Occupy the receptor and prevent the agonistic compound from having any affect on the cell
* blockers
