ch.4 Flashcards
Define pharmacodynamics
The study of how the effects of a drug are manifested
_____ is The study of how the effects of a drug are manifested
pharmacodynamics
What is the mechanism of action
Method by which a drug elicts effects
( how the drug shows that it is working)
3 methods
____
1. Drug -receptor interaction
- Drug enzyme interaction
- Nonspecific drug interactions
List the 3 methods of mechanism of action
- Drug-receptor interactions
- —-A. Stimulation (Agonist)
- —-B. Blockade ( antagnoist) - Drug enzyme interactions
- Non specific interactions
What is an example of drug interactions…
Define that
Non specific interaction
It is a not specific interaction that does not meet criteria of drug receptor or drug enzyme
Specific biological sites located on a cell surface or within a cell is known as ____
Receptors
– Like keyholes in which certain drugs will fit in
Drugs will have an affinity (attraction) for ____ only
specific cells
What is Antagonist
When drug stops or blocks a cell from performing some function
What is the function of an agonist
Stimulates/ enhances the body’s natural response to stimulation
Strong affinity ( attraction) for a receptor allows a a drug to elicit 1 of 3 things
1) ____
2) ____
3) ____
- Agonist
- Antagonist
- mixed agonist/ antagonist
Any organ or organ system in the body on or in which the desired effect occurs
Target organ
Name the drug receptor interaction
- Stimulation ( Agonist)
2. Blockade
Antagonist
Enzymes are generally considered _____ and why?
catalyst
because the initiate biochemical reactions
When does a drug enzyme interaction occur?
When a drug resembles the substrate to which an enzyme usually attaches
Define efficacy
aka: Effectiveness
Degree to which a drug is able to produce the desired effect
( how well the drug works)
Define potency
Relative concentration required to produce the effect
Define half life of drug response relationshios
Time required for current serum drug concentration to decline by 50%
ratio between lethal dose & effective dose
Therapeutic Index
the dose at which a drug is lethal to 50% of the population
Lethal dose
The dose required to produce a therapeutic effect in a 50% of the population
Effective dose
the closer the ratio is to ____ , the more dangerous the drug
1
- you always want LD 50 to be a high #, greater than 1
Define adverse effect
Any unwanted effect
always bad
what is side efffect
Predictable pharmacologic action on body systems other than the action intended
- good or bad
When can a normal dose can become toxic
if metabolism or elimination is impaired
Can an allergic reaction be a side effect?
No because it is not a predictable effect
Toxicity and allergic reactions are always considered ____ effect.
Adverse
No drugs are completely _____!!
Safe ,
there is always a toxic level
____ is when two drugs act together to give a pharmacologic response that is greater than the additive response expected
synergism
____ is when two drugs with different chemical composition are paced together, they may precipitate to an insoluble complex or may chemically destroy their activity
Chemical incompatibility
