Chapter 3 Flashcards
what is tolerance
Drug tolerance is defined either as the decreased effec-tiveness (or potency) of a drug that results with repeated administrations, or as the necessity of increasing the dose of a drug in order to maintain its effectiveness after repeated administrations.
all the effects of a drug diminish at the same rate
f dif tolerances for each effect
it is more appropriate to think of tolerance developing to the ….
…. rather than to the drug itself
various effects of a drug
what is cross tolerance
when tolerance to one drug diminishes the effects of another drug
when do we usually see cross tolerance
memvbers of the same drug class
why is cross tolerance with members of same drug class
evidence that the drugs may be producing their effect by common mechanisms.
does tolerance last indefinatly
no may also depend of environment
does tolerance always develop after repreated administrations
it can also occur during a single drug administration.
T: —tolerance that has developed during a single administration.
acute tolerance
what is acute tolerance
The effect will peak before the blood level peaks, and the effect will be gone before the drug is entirely eliminated from the body.
figure 3.1
explain whats happening in graph
what does pharmacokinetic mean
drug movement”
3 areas of pharmacokinetics?
absorption, elimation distribution
an increase in the rate or ability of the body to metab-olize a drug, resulting in fewer drug molecules reaching their sites of action.:T
Pharmacokinetic tolerance (also called metabolic tolerance or dispositional tolerance
what is Pharmacokinetic tolerance (also called metabolic tolerance or dispositional tolerance usually the result of
an increase in the level of an enzyme the body uses to break down the drug
how does pharm tolerance change effect drug has
all effects of the drug will be dimin-ished because of the diminished concentration of the drug at the site of action is less
can pharm tol create cross tolerance
yes
The term pharmacodynamic means “…”
drug change” and refers to a drug’s effects on the body, including various physiolog-ical processes
Pharmacodynamic tolerance (also called physio-logical tolerance or cellular tolerance) arises from …
adjustments made by the body to compensate for an effect caused by the continued presence of a drug.
pharmdynamic tol is the result of …
homeostasis to a set point
how does pharodynamic effect drug effect
This means the drug will have a smaller and smaller effect the more it is adminis-tered. because body gets better at returning to set point
nerve cells communicate with one another by releasing a substance called a …, which interacts with specialized molecules called … sites on the membrane of a neighboring nerve cell.
neurotrans-mitter, receptor
Some drugs work by blocking these receptor sites and reducing the effect of the neurotransmitter. what is bodies reponse (pharmodynamic)
There is a homeostatic mechanism that detects when this happens and the cell can respond in a number of ways, such as by manufacturing more receptor sites, increasing receptor-site sensitivity to the neurotransmitter, or by increasing the synthesis and release of the neurotransmitter.
There is a homeostatic mechanism that detects when this happens and the cell can respond in a number of ways, such as by manufacturing more receptor sites, increasing receptor-site sensitivity to the neurotransmitter, or by increasing the synthesis and release of the neurotransmitter. :T
upregulation