Phamacology Flashcards
(133 cards)
1
Q
Define pharmacology
A
Study of the actions and effects of chemicals on body and body on chemicals
2
Q
What are the main 2 components of pharmacology
A
Pharmacokinetics
Pharmacodynamics
3
Q
Define pharmacodynamics
A
Drugs effect on body
4
Q
Define pharmacokinetics
A
Bodys effect on drugs
5
Q
3 considerations of drugs in terms of pharmacodynamics
interaction with …, what about drug, modifies?
A
Interaction with cells
Effect of drug concentration on body
Drug modifying disease
6
Q
3 properties of drugs
A
Affinity
Efficacy
Potency
7
Q
Define affinity
A
Ability of drug to bind to receptor
8
Q
Define efficacy
A
Ability of drug to induce an response
9
Q
Define potency
A
Amount of drug required to illicit desired response
10
Q
What is the equation for potency
A
Affinity + efficacy
11
Q
List 4 families of receptors for drugs
A
Ligand gated ion channels
G coupled protein receptors
Enzyme linked receptors
Intracellular receptors
12
Q
List 4 drug action sites
A
Enzymes
Receptors
Carriers
Ion channels
13
Q
What are 2 ways things a drug can act as?
A
As an agonist or an antagonist
14
Q
List 3 types of agonists
A
Full agonist
Partial agonist
Inverse agonist
15
Q
List 3 types of antagonists
A
Antagonists
Competitive antagonists
Non-competitive antagonists
16
Q
Define a full agonist drug
A
Drug that binds to receptor to initiate a response
17
Q
What do agonist drugs mimic?
A
Body’s function
18
Q
What are 2 features of a full agonist
A
High affinity and efficacy
19
Q
Define a partial agonist drug
A
Drug that binds to a receptor to initiate a response but without the efficacy of a full agonist
20
Q
Partial agonists can act as what when given with a full agonist?
A
Competitive agonist
21
Q
Define a inverse agonist drug
A
Drug that binds to a receptor to initiate the opposite response e.g. naloxone on opioid receptors
22
Q
Define a antagonist drug
A
Drug that binds to a receptor to initiate no response/prevent response from occurring
23
Q
Define a competitive antagonist drug
A
Drug that binds to same receptor as another drug/ligand thus competes for receptor site
24
Q
Define a non-competitive antagonist
A
Drug that binds to a different site on receptor leaving the receptor ineffective
25
What do dose response curves show?
Body's response to drug against logarithmic dose
26
On a dose response curve graph what does the X axis demonstrate about which feature of a drug (i.e. efficacy, potency, affinity)?
(which direction is highest to lowest)
X axis demonstrates a drugs potency from highest to lowest (left to right)
27
On a dose response curve graph what does the Y axis demonstrate about which feature of a drug (i.e. efficacy, potency, affinity)
(which direction is highest to lowest)
Y axis demonstrates a drugs efficacy and affinity from lowest to highest (bottom to top)
28
True or false, modified forms/doses of drugs should never be crushed or chewed?
True
29
3 considerations of drugs in regards to pharmacokinetics
| route, time, exit
Process of absorption from administered route
Period between administration and effect
Process of elimination from body
30
What are the 4 stages of pharmacokinetics?
```
ADME
Absorption
Distribution
Metabolism
Excretion
```
31
Define absorption
| from where to where
Transfer of drug from administered site into systemic circulation
32
What % of drug is absorbed in how many hours given via oral route?
75%
| 1-3 hours
33
What 3 cause the loss of 25% of a drug administered orally?
GIT acid
Enzymes
1st pass metabolism
34
First pass metabolism only occurs when drugs are taken orally?
True
35
List 6 factors that effect oral absorption of a drug
```
Particle size
Formulation
Enzymes and pH of GIT
GIT motility
Physiochemical factors e.g. salt form
Food eaten
```
36
What would inactivate a drug to mean that it couldn't be given orally?
Drugs left inactive due to first pass metabolism
37
Define a depot and what does it mean for speed of absorption?
Drug given in a suspension
| Allows for slow sustained absorption
38
What type of substance does a specialised depot come in and what does does this mean for absorption?
Oily substance
| Slow absorption
39
Drugs given IM in an aqueous solution have fast or slow absorption?
Fast
40
Which 2 routes can suspensions be given into?
IM or subcut
41
What is the bioavailability of a drug given IV?
100%
42
Define distribution
Process where drug is reversibly transferred
43
Name 2 methods of distribution
| clue: transfer, distance
Bulk flow transfer - in blood
| Diffusion transfer - molecule by molecule through phospholipid bilayer
44
How are drugs reversibly transferred?
By binding to plasma proteins
45
Name 2 proteins that help transfer drugs
Albumin
| Glycoproteins
46
True or false, drugs are chemically inert when bound to plasma proteins
True
47
List 4 methods by which drugs cross cell membrane
Passive diffusion
Facilitated diffusion
Active transport
Pinocytosis
48
During passive diffusion what concentration do drugs move from to?
High to low concentration
49
What drug action site facilitates passive diffusion?
Ion channels
50
What drug action site facilitates facilitated diffusion
Protein carriers
51
Which is quicker facilitated or passive diffusion?
Facilitated
52
What does active transport allow for in terms of drug concentration?
Movement of drug against concentration gradient
53
What does a drug need to be soluble in to be able to cross the blood brain barrier?
Lipid soluble
54
List 5 factors that effect drug distribution
```
Plasma protein binding
Location of receptor site
Regional blood flow
Lipid solubility
Disease
```
55
How do pregnancy and liver conditions effect distribution of drugs?
Reduce albumin concentration
56
What would you do to the dose of a drug if a patient had low albumin levels and why?
Reduce dose
| As drug is bioactive when unbound increasing likelihood of ADRs and toxicity occurring
57
What does the % of protein binding of a drug have to be for displacement of another protein bound drug to be clinically significant?
90%
58
Define narrow therapeutic index
Drug with a small difference between therapeutic and toxic concentrations
59
What do you need to do when a pt is prescribed a drug with a narrow therapeutic index
Monitor blood plasma concentrations of drug
60
What tissue is responsible for the difference in drug distribution in children and the elderly?
Adipose tissue
61
List 6 factors effecting metabolism
```
1st pass effect
Perfusion of liver
Liver disease
Generic factors
Other drugs
Age
```
62
Define bioavailability
% of drug that makes it into systemic circulation
63
Define bioequivalence
Drug that has no difference in its rate of uptake/action at receptor site when given at same dose via same route
64
List 4 outcomes of metabolism
Activation of inactive drug
Increased activity of already activated drug
Inactivation of active drug
Change in activity of drug
65
List 4 metabolic barriers
GIT mucosa
Lung
Liver
GIT wall
66
What is the main site of local hormone metabolism?
Lungs
67
Define clearance
Measure of the time it takes for a volume of blood plasma to be completely clear of a drug
68
Clearance a measure of the time it takes for a drug to be removed from blood plasma OR a measure of the amount of drug removed from blood plasma?
Measure of TIME of drug removal not amount
69
Define half life
Time taken for plasma concentration of a drug to halve
70
True or false, half life is effected by the dose of drug taken?
False
71
What does an enzyme inducing drug do to the bioavailability of another?
Reduces bioavailability
72
When given an enzyme inducing drug, what might you have to do to the dose of the original drug?
Increase dose
73
What does an enzyme inhibiting drug do to the bioavailability of another?
Increases bioavailability
74
When giving an enzyme inhibiting drug, what might you have to do to the dose of the original drug?
Decrease dose
75
What does the liver do to help with the elimination of drugs from the kidneys?
Metabolises/breaks down drugs so that they are more water soluble to help with excretion from the kidneys.
76
List 4 stages of excretion of drugs from the kidneys
Filtration
Re-absorption
Secretion
Excretion
77
What 2 types of drugs are reabsorbed by the kidneys during excretion?
Lipid soluble
| Unionised
78
What type of membrane transport occurs during secretion in excretion of drugs from the kidneys?
Active transport by membrane carriers
79
Where in the kidneys does secretion of drugs during excretion occur?
Transporters in the PCT membrane
80
Define rate of absorption
Speed at which drug is transferred from administered route into systemic circulation
81
Define extent of absorption
Amount of total drug transferred from administered route into systemic circulation
82
What does increased GIT motility do to the rate of absorption?
Increases rate of absorption
83
What does hyper GIT motility do to the extent of absorption?
Decreases the extent of absorption
84
Name 4 routes that require absorption into systemic circulation first before they are able to take effect
Inhalation
Oral
Vaginal
Ocular
85
What 2 factors determine receptor effect?
Rate and extent of absorption
86
What about a drug determines it's rate and extent of absorption?
Size of drug particles
87
During decreased GIT motility is there a change in the extent of absorption?
No
88
List 5 barriers between oral route and drug receptor site
GIT mucosa
Vascular endothelium
Renal tubule cells
Blood brain barrier
89
Lipid soluble drugs cross the cell membrane by what form of transport?
Passive diffusion
90
What happens to the blood brain barrier during inflammation and what does this allow in terms of drug solubility?
Becomes leaky
| Allows for water soluble drugs to cross from blood plasma into CSF
91
What type macromolecule is present in a drug meaning that it is unsuitable to be given via the oral route?
Proteins e.g. insulin
92
What route should protein containing drugs be given via?
Injection
93
What is the name given to drugs that are inactive until activated by being metabolised?
Prodrugs
94
Which 2 groups of drugs are important to substitute for one that is bioequivalent?
Mood enhancing drugs
| Anti-epileptics
95
What 3 compartments is water and thus drugs distributed into?
Intracellular
Extracellular
Adipose tissue
96
What is volume of distribution used to work out?
Dose of drug needed to reach certain plasma concentration
97
Does a highly protein bound drug have a high or low volume of distribution?
Low
98
Does a highly lipid soluble drug have a high or low volume of distribution?
High
99
Do water soluble drugs need to be metabolised to be excreted into the urine?
No
100
What does a phase I reaction do to a drug?
Makes it more chemically reactive
101
What does a phase II reaction do to a drug?
Adds water via a process called conjugation to make drug inactive and able to be renally excreted
102
Drugs excreted into the bile end up being excreted via what?
The faeces
103
What stage of renal excretion removes large protein bound drugs?
Secretion
104
What % of small water soluble drugs are removed by filtration?
20%
105
Define teratogenic
Drugs able to cross the placenta during 1st trimester leading to congenital malformations
106
List 7 factors that effect transfer of drug from mother to foetus via placenta
```
Concentration of drug
Blood flow via placenta
Anion or cation
pH of maternal blood
Protein affinity
Lipophilicity
Molecular weight
```
107
What does pharmacodynamics allow for the prediction of?
A drugs effect and ADRs
108
Name 3 target molecules for drugs
Enzymes
Transport mechanisms
Receptors
109
What is a ligand?
Molecule that binds to receptors initiating a response/preventing a response thus regulating bodily functions.
110
Name 2 locations of receptors
Intracellular
| Plasma membrane bound
111
List 5 classes of plasma membrane receptor
```
Adrenoreceptors
Dopamine
Opioid
5HT
Acetylcholine
```
112
What ligand binds to a 5HT receptor?
Seritonin
113
What ligand binds to adrenoreceptors?
Adrenaline and noradrenaline
114
How many types of andrenoreceptors are there?
4
115
What are the 4 types of andrenoreceptors called?
alpha 1
alpha 2
beta 1
beta 2
116
Name the 4 locations of beta 1 andrenoreceptors?
Heart
GIT smooth muscle
Glandular tissue
Nerve terminals
117
Stimulation of beta 1 andrenoreceptors in the heart causes what?
Increase in heart rate and force of contraction
118
Stimulation of beta 1 andrenoreceptors on smooth muscle stimulates what?
Relaxation
119
Stimulation of beta 1 andrenoreceptors on glandular tissue stimulates what?
Increased secretion
120
Stimulation of beta 1 andrenoreceptors on nerve terminals stimulates what?
Increased neurotransmitter release
121
Name the 4 locations of beta 2 andrenoreceptors
Liver
Vascular, uterine, bronchial, bladder smooth muscle
Skeletal muscles
Mast cells
122
Stimulation of beta 2 andrenoreceptors in the liver stimulates what?
Glycogenolysis
123
Stimulation of beta 2 andrenoreceptors on skeletal muscle causes what?
Tremour
124
Stimulation of beta 2 andrenoreceptors on mast cells stimulates what?
Decreased histamine release
125
Stimulation of beta 2 andrenoreceptors on smooth muscle stimulates what?
Relaxation
126
Where are beta 2 smooth muscle receptors located?
Uterine, bladder, bronchial and vascular
127
Where are beta 1 smooth muscle receptors located?
GIT
128
How many types of 5HT receptors are there?
3
129
How many types of acetylcholine receptors are there and what are their names?
2
Muscanic
Nicotinic
130
How many types of dopamine receptors are there?
4
131
What endogenous ligand to intracellular receptors usually bind to?
Steroids
132
Explain the mechanism of drugs that bind to intracellular receptors
(which part of the cell do they go to to change what, causing what change to cell metabolism)
Drug receptor complex moves to nucleus where it changes gene transcription
Change in gene transcription changes protein synthesis.
133
Steroids bind to which type of receptor?
| located where
Intracellular
