Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Didactic Year > Receptor Pharmacology, Pharmacokinetics, Pharmacodynamics > Flashcards

Receptor Pharmacology, Pharmacokinetics, Pharmacodynamics Flashcards

1
Q

Pharmacology

A

Study of drugs and their interactions with the human body

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

Drug

A

Any chemical agent that affects the living part of a cell

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

Adverse Drug Reaction (ADR)

A

Response to a drug that is harmful and unintended. (sometimes we use drugs such as “benadryl” for insomnia, rather than it’s intended purpose as an antihistamine)

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

Pharmacokinetics

A

Action of the body on a drug. The study of the fate of drugs. The absorption, distribution, metabolism (biotransformation), and elimination of drugs.

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

Understanding pharmacokinetics can

A

Increase the probability of therapeutic success and reduce the occurrence of adverse drug effects

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

we use pharmacokinetics to determine

A

The proper drug to use, route of administration, dosing schedules

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

Absorption of drugs

A

Movement of a drug from its site of administration into circulation and the extent to which it occurs

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

Solid dosage absorption requires

A

Dissolution of the tablet or capsule

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

Ways absorption can occur

A

Via active (against concentration gradient with energy), or passive (from higher to lower concentration) diffusion.

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

Drug interactions commonly occur during

A

Movement through the gi tract (food, etc.)

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

Bioavailability (F) of drugs

A

The fractional extent to which a dose of drug reaches its site of action

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

Factors that decrease bioavailability

A

Gi absorption, hepatic first pass effect/metabolism

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

Hepatic first pass effect

A

Pre systemic metabolism. The drug passes through the liver the first time and is nearly gone: high first pass rate

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

Places a drug in circulation can go

A

The therapeutic site of action, or unwanted sites of action

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

We can bypass gut absorption issues with

A

IV formulations

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

Distribution of drugs

A

Occurs after absorption, when the drug is transported to a site where it reacts with various bodily tissues and/or receptors

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

The rate of drug delivery is determined by

A

Cardiac output, regional blood flow, capillary permeability, and tissue volume

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

What areas initially receive most of the drug?

A

Liver, kidney, brain, and other well perfused organs.

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

Second distribution phase

A

Slower than first. Delivers to muscle, most viscera, skin, fat. Involves a far larger fraction of body mass.

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

What limits concentrations of free drug

A

Binding of drug to plasma proteins and tissue macromolecules

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

Determinants for distribution

A

Lipid solubility and transmembrane pH

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

Prolonged drug affects occur with

A

Lipid soluble drugs, stored in adipose tissue with low blood flow. (highly lipid soluble drugs include benzodiazepines, barbiturates, phenothiazines)

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

Metabolism of drugs

A

Mainly occurs in the liver. Body converts active lipid soluble compounds to inactive water soluble substances to be primarily excreted by the kidneys

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

What is phase I of drug metabolism?

A

Hepatic microsomal enzymes oxidize, demethylate, and hydrolyze drugs. (drugs with short half lives and inactive metabolites are almost entirely during first pass)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Phase 2 of drug metabolism?
Large water soluble substances are attached to the drug. (compounds may circulate through one or both phases multiple times until water soluble characteristics are present)
26
Do more drug interactions occur during phase I or 2 of drug metabolism?
Phase 1 (more DI’s are caused by phase 1 hepatic enzymes)
27
Hepatic microsomal enzymes
Important group in phase 1, characterized by cytochrome P450 isoenzymes. More commonly induced/inhibited by other drugs. (numerous forms)
28
CYP450 System
Is responsible for the oxidation of many drugs
29
What affect do drugs have on CYP metabolism?
Drugs can act as substrates, inhibitors, and inducers of this metabolism
30
Which CYP families are primarily involved with drug metabolism?
CYP families 1,2,3, and 4
31
Enzyme inhibitors
Decrease the rate of metabolism of object drug by obstructing metabolizing enzyme
32
Inhibition of an enzyme causes
Increased drug concentration, increased half life, accumulation, and can lead to toxicities
33
Enzyme induction
Stimulates the increase of cyp450 enzyme activity. Increases clearance of drug
34
What is the prototype inducer?
Phenobarbital
35
Drug excretion/elimination
Process that removes drug and its metabolites from the body. (primarily through the urine)
36
Excretory organs eliminate polar compounds more efficiently than
Substances with high lipid solubility
37
Lipid soluble drugs are only readily eliminated once they are
Metabolized to more polar compounds
38
What is the most important organ for excretion?
The kidneys
39
Substances excreted in feces are
Principally unabsorbed orally ingested drugs or drug metabolites
40
Anesthetic gas is excreted through
The lungs
41
Factors affecting pharmacokinetic principles
Age, sex, weight, disease states, genetic factors (all 4 principles can vary from pt to pt)
42
Pharmacodynamics
Action of the drug on the body. The study of the biochemical and physiological effects of drugs and their mechanisms of actions. (can provide the basis for the rational therapeutic use of a drug)
43
What are the most common mechanisms for drug interactions?
Synergism, antagonism, altered cellular transport, and effects on receptor sites.
44
Four most important parameters governing drug disposition are
Bioavailability, volume of distribution, clearance, and elimination
45
Volume of distribution
Relates the amount of drug in the body to the concentration of drug in the blood or plasma depending on the fluid measured.
46
Half life
The time it takes for the plasma concentration to be reduced by 50%.
47
Steady state
Amount of drug administered in a given period (maintenance dose) is equal to the amount in the eliminated in that same period. ( Rate in = rate out )
48
Approximate how long does it take to reach steady state
About 5 half lives
49
Classifications of drug interactions
Can be pharmacokinetic or pharmacodynamic
50
Types of drug interactions
Drug-drug, drug-food, drug-disease
51
Pharmacokinetic DIs
Occurs when ADME of one drug is affected by another drug/agent
52
Absorption drug interactions
Can occur in the gi, due to ph, chelation, increase or decrease in motility, or changes in the GI flora.
53
Distribution drug interactions
Drugs bound to proteins, “free" unbound drugs are active
54
Metabolism drug interactions
CYP450 inducers include cigarette smoking and phenytoin, and CYP450 inhibitors include grapefruit juice and erythromycin
55
Elimination drug interactions
Ex: competition can occur between two drugs over elimination. In the case of probenecid and penicillin, probenecid is excreted first. This causes an increased concentration of penicillin due to decreased elimination.
56
Synergistic effects
Also known as additive effect, example is beer and Valium
57
Antagonistic effects
Opposing effects, work against each other (2+2=1)
58
Potentiation/synergism
Interaction between 2 or more drugs creating a pharmacologic response greater than the sum of the individual drugs (1+1=5)
59
Receptor
Molecule to which a drug binds to bring about a change in function of biologic system
60
Receptor site
Specific region of receptor molecule where drug binds
61
Inert binding molecule
A molecule to which a drug can bind without changing any function
62
Max efficacy
Maximum effect that can be achieved with a particular drug regardless of dose
63
Potency
The amount of drug needed to produce a given effect (determined by affinity of receptor for the drug and number of receptors)
64
ED50
Dose that causes 50% of maximum effect
65
TD50
Median toxic dose, dose where toxicity occurs in 50% of cases
66
LD50
Median lethal dose, dose where death occurs in 50% of cases
67
Therapeutic index (TI) subtracted by TD50
Equals ED50
68
Agonist
A drug that activates its receptor upon binding
69
Partial agonist
Drug that binds to receptor but produces a smaller effect at full dosage than a full agonist
70
Allosteric agonist
Drug that bind to the receptor molecule without interfering with normal agonist binding. They also alter the response with normal agonist
71
Antagonist
Drug binds without activating its receptor and preventing activation from an agonist
72
Competitive antagonist
Pharmacologic antagonist that can be overcome by increasing the concentration of agonist
73
Irreversible antagonist
Cannot be overcome by increasing agonist concentrations, “irreversibly” binds to the receptor site
74
Physiologic antagonist
Drug that counters the effect of another by binding to a different receptor and causing opposing effects
75
Chemical antagonist
Drug that counters the effect of another by binding to the agonist drug (not the receptor)
76
Allosteric antagonist
Binds to receptor molecule without interfering with normal antagonist binding but alters response to binding
77
Signaling
Once an agonist drug has bound to its receptor, some effector mechanism is activated. Drug-receptor interactions, 5 major types
78
Receptor regulation
Regulated in number, location, and sensitivity. Changes can occur over minutes or days
79
Tachyphylaxis
An acute decrease in the response to a drug after its administration. (Frequent or continuous exposure to agonists resulting in short term reduction of receptor response)
80
Receptor downregulation
Long term reductions in receptor number which occur in response to continuous to agonists
81
Receptor upregulation
Increases in receptor number when receptor activation is blocked for prolonged periods by antagonists
82
Receptor-Effector systems
Enzyme in intracellular space Neurotransmitter reuptake transporters Voltage-activated ion channels
83
Transmembrane enzymes
Drug binds to extracellular component to activate an enzymatic reaction in the intracellular component (outer domain = receptor, inner domain = effector)
84
85
86

Didactic Year (24 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions