Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Pharmacology > Principles of Pharmacology > Flashcards

Principles of Pharmacology Flashcards

1
Q

What is a drug

A

a chemical substance of known structure other than a nutrient or essential dietary ingredient, which, when given to a living organism produces a biological effect

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the most common target for drugs

A

proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the 4 different protein targets

A

transmembrane receptors
enzymes
carriers (transporters)
ion channels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What effect does an agonist have on a receptor

A

it activates a receptor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what effect does an antagonist have on a receptor

A

it blocks activation of a receptor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Selectivity

A

the higher the selectivity the more precise it is in the receptor it bonds to. very selectively bonds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is affinity

A

the strength with which the drug binds to the receptor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what is efficacy

A

how well the drug activates the receptor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what is the affinity/efficacy of a good agonist

A

it should have high affinity and high efficacy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what is a full agonist

A

a drug that completely activates the receptor (100% efficacy) takes the receptor to emax

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is Emax

A

100% efficacy, or the maximum response a drug can get out of a receptor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what is a partial agonist

A

a drug that activates the receptor but doesn’t get a full response (doesn’t ever reach emax no matter the concentration)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the affinity/efficacy an antagonist

A

high affinity and low efficacy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What does the DRC show

A

the DRC is the dose response curve and it shows us the receptors response (Y axis) to a drug with increasing concentration (X-axis, log scale)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is intrinsic activity

A

the efficacy (how well the drug activates the receptor)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the EC50

A

the concentration of a drug required to get 50% of its own maximum efficacy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what is the EC50 used for

A

to show “effective concentrations” of the drug

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is potency

A

the amount of drug required to produce a given effect (EC50 is often the desired effect measured)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

something that has high potency…

A

requires low concentrations to get your desired effect

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is a competitive antagonist

A

an agonist the competes for the same binding site as the agonist

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is a reversible antagonist

A

same thing as a competitive antagonist

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What happens to the dose response curve in the presence of a competitive antagonist

A

it shifts to the right (this means that in the presence of the competitive antagonist higher concentrations are required to get the same effect as lower concentrations not in the presence of the competitive antagonist)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is a non-competitive antagonist

A

an antagonist that can’t be overcome by the agonist, no matter the agonist concentration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

what is an irreversible antagonist

A

the same thing as the non-competitive antagonist

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

what happens to the dose response curve in the presence of a non-competitive antagonist

A

the curve shifts down (this is because the non-competitive antagonist completely inactivates the receptors so that no matter the dose of agonist it can’t get back to emax in the presence of the non-competitive antagonist

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

what is allosteric modulation

A

when a drug acts on a different site than the normal ligand, but causes a change in the receptor which alters the response (can be negative and positive)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is the Quantal dose response curve

A

dose on the X axis

percentage of population exhibiting therapuetic effect on the Y axis (as opposed to % of receptor activation)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

what is ED 50

A

the dose of drug at which 50% of the population receives the desired effect

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

what is LD 50

A

the dose of drug at which 50% of the population dies from toxicity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

what does the therapeutic index of a drug tell us

A

how safe the drug is.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

how do you calculate the therapeutic index

A

LD50/ED50

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

what does a high therapeutic index tell you

A

that the drug is safe (it takes a lot of the drug to kill 50% of the population in comparison to what it takes for 50% of the population to get its benefits)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What is toxicity

A

an adverse drug reaction that occurs when the dose is too high (acts on similar mechanism to the therapeutic effect)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

what is a side effect

A

an adverse drug reaction that occurs within the therapeutic dose range

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

what is a drug allergy

A

an adverse immune reaction to the drug

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

what is an idosyncratic reaction

A

an adverse reaction to a drug that is due to the genetics of the patient (not immune based)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What is a pharmacokinetic interaction

A

a drug-drug interaction in which one drug affects the metabolism, excretion, or absorption of the other

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

what happens in a pharmacokinetic interaction when drug A increases the metabolism of drug B

A

concentration of Drug B decreases as well as its effect

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

what happens in a pharmacokinetic interaction when drug A decreases the excretion of drug B

A

concentration of drug b increases as well as its effect

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

what happens in a pharmacokinetic interaction when drug A decreases the absorption of drug B

A

concentration of Drug B decreases as well as its effect

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

What is a target drug-drug interaction

A

when drugs bind to the same receptor (can be same site or not)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

what are the potential consequences of a target drug-drug interaction

A
  1. they can both increase the same effect which leads to excessive action of the drugs
  2. one can block the action of the other which leads to inadequate action of the blocked drug
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

What is synergism

A

when a drug causes a greater effect than normal in the presence of another drug

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

What affect did the 1906 Wiley act have

A

it prohibited the manufacturing and shipment of adulterated and misbranded foods and drugs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

what affect did the 1914 Harrison Narcotic act have

A

regulated opiates and cocaine

46
Q

what affect did the 1938 food, drug and cosmetic act have

A

mandated the FDAs role in regulating the safety of drugs

47
Q

what affect did the 1952 Durham-Humphrey act have

A

called for certain drugs to be prescription only

48
Q

what affect did the 1983 orphan drug amendment have

A

it provided incentives for developping drugs for rare diseases

49
Q

what affect did the 1997 FDA modernization act have

A

allowed manufacturers to discuss off label uses for drugs and streamlined approval for drugs treating life threatening conditions

50
Q

what affect did the 2005 combat methamphetamine epidemic act have

A

new regulations for sale of ephedrine, psuedoephedrine, and phenylpropanolamine

51
Q

what affect did the 2016 21st century cures act have

A

$6.8 billion for treating opiod abuse, cancer research, and for expanding mental health care

52
Q

What are the two things the FDA requires drug manufacturers to prove about their drugs

A

that they are safe and effective

53
Q

what are the steps of clinical drug tests

A
  1. drug discovery
  2. preclinical development
  3. phase 1 - testing in healhty individuals
  4. phase 2- small scale testing in patients
  5. phase 3 - large scale controlled trials
  6. regulatory approval
  7. postmarketing surveilling
54
Q

What is the regulation system for drugs to be used during pregnancy

A

used to be categorized from A - D and X (based on how safe they are)
now uses narrative structure to convey potential risks

55
Q

What are the four things that happen to a drug in the body

A 
ADME
Absorption
Distribution
Metabolism
Excretion
56
Q

how do we think of the body in terms of distribution of drugs

A

like a series of well stirred compartment (well stirred meaning the concentration in a compartment is uniform throughout the entire compartment)

57
Q

What are the 3 barriers drugs must cross to move from compartment to compartment

A
  1. cell membranes (ICF vs. ECF)
  2. epithelial barriers (GI mucosa, renal tubules)
  3. vascular endothelium (plasma and interstitial water)
58
Q

how does the permeability of vascular endothelium change in different locations in the body

A

low permeability - tight junctions - BBB

high permeability - fenestrated junctions - kidneys

59
Q

what are the four ways drugs can cross cell membranes

A
  1. diffusion through lipid bilayer
  2. diffusion through aqueous channels
  3. via carriers (ATP-ases)
  4. pinocytosis (insulin)
60
Q

What is the main determinate of a drugs ability to diffuse through lipid bylayer

A

solubility in the membrane

- lipophilic, uncharged, small

61
Q

drugs are often weak acids or bases that exist in ionized and unionized forms what determines whether they are ionized or not

A

the pKa of the drug and the ph of the fluid they are in.

62
Q

which is going to pass through the lipid membrane better, the ionized or unionized form of the drug

A

the unionized form (no charge = more lipophilic)

63
Q

what is ion trapping

A

when there is a large pH difference between adjacent compartments. in one compartment the pH is such that the drug exists as the unionized form so it is more able to permeate the membrane. in the other compartment the pH is such that the drug exists in the ionized form and thus can’t permeate cell membranes.

64
Q

What happens to a weak acid drug in a acidic environment

A

the weak acid drug is mostly unionized and thus can permeate

65
Q

how do we think of acids and bases in the simple way

A

acids try to give away H

bases try to steal H

66
Q

what happens to a weak acid drug in a basic environment

A

the weak acid drug becomes mostly ionized and becomes ion trapped

67
Q

what happens to a weak base drug in a basic environment

A

the weak base drug is mostly unionized and thus can permeate

68
Q

what happens to a weak base drug in an acidic environment

A

the weak base becomes mostly ionized and becomes trapped

69
Q

What determines how much of a drug will go to adipose tissue

A

hydrophilic drugs won’t go to fat very much

highly lipophilic drugs will be come concentrated in fat

70
Q

what is a complication in highly lipophilic drugs

A

they become concentrated in fat so they are less predictable and often less effective (especially in patients with lots of fat)

71
Q

what is absorption of a drug

A

a drugs movement into the plasma

72
Q

What are enteral routes of drug administration

A

routes through the GI tract

  • oral
  • sublingual
  • rectal
73
Q

what is the benefit of sublingual drug administration

A

it bypasses the hepatic portal system (avoids first pass metabolism)

74
Q

what are parenteral routes of drug administration

A

routes not through the GI tract

  • topical
  • inhalation
  • injection
75
Q

how long does it take for an orally taken drug to be 75% absorbed

A

1-3 hours

76
Q

what is bioavailabilty

A

the fraction of an orally administered drug that reaches systemic circulation

77
Q

what affects the bioavailabilty of a drug

A

intestinal and hepatic enzymes that metabolize the drug before it can be absorbed
(drug preparation and genetics of the individual affect how much of the drug is metabolized)

78
Q

What is a bioequivalent drug

A

a generic drug that reaches similar plasma concentrations in a similar amount of time and for a similar duration.

79
Q

what does bioequivalence imply

A

that the generic drug can be substituted for brand name drugs and the outcomes will be similar

80
Q

what compartments is the body water divided into, and what are the ratios of the total water

A

intracellular fluid = 2/3 of the total body water
extracellular fluid = 1/3 of total body fluid
- plasma = 8%
- interstitial fluid = 25%

81
Q

What is the total body water in an average person

A

42 L

  • 28 L = ICF
  • 14 L = ECF
    • 9.5 L = interstitial fluid
    • 3.5 L = plasma
82
Q

What is the volume of distribution

A

the total amount of drug in the body/ divided by the plasma concentration

Vd = Q/Cp

83
Q

what does the volume of distribution represent

A

the volume of fluid that would be needed to contain all of the drug given, at the same concentration as measured in the plasma

84
Q

What does a high volume of distribution mean

A

that the drug is highly distributed into the tissues

85
Q

What is a prodrug

A

a drug that starts as an inactive precursor, that upon metabolism becomes activated

86
Q

what are the two processes by which drug elimination occur

A

metabolism

excretion

87
Q

What are the two phases of drug metabolism

A

phase 1 - catabolism

phase 2 - anabolism

88
Q

what are the different routes of elimination from the body

A

kidneys
hepatobiliary system
lungs
fecal

89
Q

what is the product of phase 1 of metabolism usually like

A

usually has a free hydroxyl group and the product can be more active than the original substrate

90
Q

what is the product of phase 2 of metabolism usually like

A

usually inactivated, and more easily excreted (except when the original compound is a prodrug)

91
Q

what is first pass metabolism and why is it important

A

the hepatic portal system takes absorbed comopounds from the gut to the liver where it undergoes some metabolism.
its important because some drugs are highly metabolized and their bioavailability becomes low

92
Q

What is enterohepatic circulation

A

when the liver transfers some compounds into bile. this acts a reservoir for the drug and prolongs it action

93
Q

what drugs are prone to enterohepatic circulation

A

glucuronides

94
Q

what are the 3 processes in renal excretion

A

glomerular filtration
active tubular secretion
passive diffusion across tubular epithelium

95
Q

what is the main determinant of whether a not a drug will undergo glomerular filtration

A

size of the particle (most drugs are small enough unless bound to proteins)

96
Q

what drugs undergo reabsorption from kidney tubules via passive diffusion

A

lipid soluble drugs (means they stay in circulation longer)

97
Q

how does the ph of urine affect secretion

A

it causes ion trapping in urine.
low ph means weak bases will be ionized, trapped, and excreted
high ph means weak acids will be ionized, trapped, and excreted

98
Q

what is TDM?

A

therapeutic drug monitoring, is when plasma drug concentration is constantly monitored.

99
Q

what is CLtot

A

clearance, the sum of all of the routes of drug clearance in the body

100
Q

how do you find the rate of drug elimination

A

Cp x CLtot

101
Q

What does it mean if you have first order kinetics of drug elimination

A

that the drug concentration is falling exponentially. that is that a certain percentage of the drugs is eliminated per unit of time

102
Q

what is the half time of a drug

A

the amount of time it takes for half of the drug to be eliminated from the body

103
Q

what is the elimination rate constant (Kel) of a drug

A

the fraction of a drug eliminated per unit of time

104
Q

what does Kel of .2/h mean

A

20 % of the drug is eliminated per hour

105
Q

how are half life and the elimination constant related

A 
t1/2 = .693/Kel
Kel = .693/t1/2
106
Q

how does a single compartment model of elimination differ from a two compartment model of elimination

A

single compartment model takes only plasma concentration into account
two compartment model takes plasma and tissues into account

107
Q

what are the two exponentials used to model a two compartment model of elimination

A 
fast = drug from plasma into tissue
slow = drug elimination from body
108
Q

what causes some drugs to be eliminated linearly as opposed to exponentially

A

saturation of enzymes (when enzymes are completely saturated they can only eliminate at a linear rate

109
Q

what is zero order elimination

A

AKA saturation kinetics, when enzymes are saturated and drugs are eliminated at a linear rate

110
Q

Why do we need to be conscious of drugs that have zero order kinetics

A

because it is hard to predict the steady state plasma concentration of the drug and thus hard to know when you are nearing overdose levels

Pharmacology (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions