Chapter 5 Pharm

the study of biochemical and physiologic effects of drugs
what drugs do to the body and how they do it

dose-response relationships
drug-receptor interactions and drug responses that do not involve receptors
interpatient variablility in drug responses
therapeutic index

the relationship between the size of an administered dose and the intensity of the response produced
as dosage increases, the response becomes larger

the minimum amount of drug to be used (least amount)
the maximum response a drug can elicit (w best response)

increasing or decreasing the dosage until the desired intensity of response is achieved

largest effect that a drug can produce
very high maximal efficacy is not alwaus more desirable

the amount of drug that must be given to produce an effect

drugs -> chemicals that produce effects by interacting with other chemicals
receptors -> special chemicals in the body that most drugs interact with to produce effects

is functional macromolecule in a cell to which a drug binds to produce its effects

enzymes, ribosomes, and tubulin
body's own receptors for hormones, neurotransmitters, and other regulatory molecules

the binding of a drug to its receptor is usually reversible

it will mimic or block the activity at the receptor site
of the endogenous regulatory molecules and increase or decrease the rate of physiologic activity normally controlled by the receptor

receptors are normal points of control of physiologic processes
under physiologic conditions, receptor function is regulated by molecules supplied by the body
drugs can only mimic or block the body's own regulatory molecules
drugs cannot give cells new functions

the fewer side effects it will produce
more selective because of receptors
doesn't happen 100% of the time

lock-and-key mechanism
does not gaurantee safety
body has receptors for each of the followingL neurotransmitters, hormones
all other molecules in the body used to regulate physiologic processes

agonists
antagonists

agonists can make processes go "faster" or "slower" **
molecules that activate receptors
endogenous regulators are considered agonists
both affinity and high intrinsic activity

produce their effects by preventing receptor activation by endogenous regulatory molecules and drugs **
drugs that block a the receptor site
affinity but no intrinsic activity
no effects of their own on receptor function

do not cause receptor activation but cause pharmacologic effects by preventing the activation of receptors by agonists

simple physical or chemical interactions with other smalll molecules
(most work by receptors)

antacids, antiseptics, saline laxatives, and chelating agents

measure of a drug's safety
ratio of the drug's LD50 (average lethal dose to 50% if the animals treated) to its ED50

the safer the drug

the less safe the drug