9 Block Flashcards
1
Q
Pharmacodynamics is
A
The actions of a drug on the body
Looks at receptor interactions
2
Q
Pharmacokinetics is
A
The action the body has on a drug
Looks at absorption, distribution, metabolism, excretion
3
Q
Therapeutic Index formula
A
TD50/ED50
4
Q
Which is safest a high or low Therapeutic Index (TI)
A
High
5
Q
What are the categories for the “old” pregnancy categories
A
A B C D X
6
Q
Pregnancy category A is
A
Safe for pregancy
7
Q
Pregnancy category B is
A
Safe (there a lot in this category)
8
Q
Pregnancy Category C is
A
There isn’t data on the effects in pregnancy
“Unknown”
9
Q
Pregnancy category D is
A
Shouldn’t use unless necessary and the benefits outweigh the risk
10
Q
Pregancy category X
A
Do not take
Can kill baby
11
Q
An agonist is
A
Drug that binds to the same site as the ligand and makes same signal
12
Q
An allosteric agonist is
A
Ligand that binds to a DIFFERENT site with no effect itself
Enhances the response
13
Q
Partial agonist is
A
A drug that binds to same receptor and produces a lower response
Inhibit agonist binding
14
Q
An antagonist is
A
Drug that binds to same receptor and inhibits the action of agonist
Has no effect itself
15
Q
A competitive antagonist is
A
A drug that binds to same receptor and inhibits action of agonist
Can be overcome by increasing agonist concentration
16
Q
A non-competitive antagonist is
A
A drug that binds to the same or different receptor and prevents agonist from binding at any concentration
17
Q
As dose increases what happens to the repsonse?
A
It increases proportionally UNTIL the max response is achieved
18
Q
Potency is
A
The concentration required to produce 50% of that drugs max repsonse (EC50)
19
Q
Efficacy is
A
The upper limit of the dose-response relation
Max effect
20
Q
Do we care more about efficacy or potency?
A
Efficacy, we care about the effect a drug has
21
Q
What is the pharmacological mechanism of antagonism
A
2 drugs
1 receptor
22
Q
What is chemical antagonism
A
2 drugs
0 receptor
23
Q
Physiological antagonism is
A
2 drugs
2 receptors
2 receptor oppose each other
24
Q
Absorption is
A
Movement of drug from site of administration to blood
25
Distribution is
The movement of drug from blood to rest of body
26
Metabolism of a drug is
Drug is converted to a form tat is easily eliminated
27
Elimination is
Removal of drug from body
28
What is the most common route of administration
Oral
29
```
Oral route of administration
Speed:
Safety:
Cost:
Absorption:
```
Speed: slow
Safety: safest
Cost: cheap
Absorption: in intestines
30
Parenteral route does what
Bypasses the GI tract
31
Buccal route of admin
Between cheek and gums
| Direct absorption
32
Sublingual RofA
```
Under the tongue
Very fast (mouth is very vascular)
```
33
Rectal R of A
Large amounts of drug can be given
| Good if pt can't keep food/liquids down
34
IM R of A
Faster absorption
| Large volume
35
SubQ R of A
Slower absorption
| Large doses
36
IV R of A
Does not involve absorption
Goes directly to blood
Most dangerous
37
Inhalation R of A
Fast
| Rapid absorption
38
What is the fastest drug form for absorption
Inhalation
39
Topical drugs are applied to the skin and effect ______
Locally
40
Transdermal drugs are applied to the skin and have a ____ effect
Systemic
41
What is passive diffusion
Most common
H>L
No carrier (cannot be saturated)
No energy
42
Facilitated diffusion
Driven by gradient
Carrier proteins (can be saturated)
No energy
43
Active transport
Against gradient
Carrier protein
Saturable
Needs ATP
44
Most drugs are one of these 2 things
A weak acid or base
45
T/F drugs pass more readily through membranes if they are uncharged?
T
46
You have HA <>H+ + A- and BH+<>B + H+
Which will easily pass through a membrane
Which will not?
HA and B
A- and BH+
47
Henderson- Hasselbalch equation
PH-pKa
48
If Henderson-Hasselbalch is - then
PH is lower than pKa, acidic
49
If Henderson-Hasselbalch is + then
PH is higher than pKa
| Basic environment
50
Is the nonionized or ionized form of a drug water soluble?
Ionized form
51
Is the non-ionized or ionized form of a drug lipid soluble?
Non-ionized
52
Page 18
Hella lot of notes
53
If you take a weak acid drug orally where will it be better absorbed?
In the stomach because there is a lower pH
54
If you take a weak base orally it is better absorbed where?
Small intestines
| Because there is a higher pH
55
If you put a drug in a like environment (acid in acid) (base in base) it will ____
Stay
56
If you put a drug its opposite environment (acid in base) it will ____
Go out
57
T/F the charged form of a drug is more easily removed from the body
True
58
T/F you can change the pH of urine to help keep or eliminate a drug from the body
True
59
If you want to get rid of a weak acid what should you do the urine
Make it basic
60
If you want to get rid of a weak base what should you do to the urine
Make it more acidic
61
If you have a weak acid overdose what should you do
Give them bicarb, makes urine more basic
62
What should you do in a weak base overdose
Give Nh4CL, makes urine more acidic
63
What are some factors that affect drug absorption
Blood flow to the absorption site
Surface area for absorption
Contact time at absorption site
64
Bioavailability is
The fraction of the administered dose that makes it to the blood
65
What are some factors that affect bioavailability
First pass metabolism
Solubility
Chemical stability
66
What is lag time
Time from administration to appearance in blood
67
What is the onset of activity
Time from administration to reaching the minimum effective concentration
68
What is the duration of action
The amount of time drug concentration stays above MEC
69
Why do most drugs bind to plasma proteins
They need a carrier protein
70
What is the volume of distribution?
Volume of drug that the drug is disseminated in
71
If you have a low Volume of distribution where is the drug?
In the blood
72
If you have a high volume of distribution where is the drug?
In the tissues
73
What does a large Vd tell you?
Most of the drug is in the extraplasmic space and it is not being delivered to the organs of elimination
74
There are drug reservoirs
Know this
75
T/F the placenta is a barrier to drugs
False
76
Look at bottom of page 24.
The different metabolisms of drugs. I dont feel like typing it all out
77
What are Phase 1 metabolisms
Accomplished by enzymes in the Smooth ER
78
What are phase 2 metabolisms
Conjugate reactions that use transferase enzyme
| They increase the size of the drug
79
What metabolism phase is missing in neonates
Phase 2
80
What is the most important site of metabolism
The liver
81
Where do phase 1 metabolisms occur
Smooth ER
82
Where do phase 2 metabolisms occur
Cytoplasm
83
What are the most active drug metabolism cytokines
CYP2C
CYP2D
CYP3A
84
What cytokine does metabolism of 50% of all drugs
CYP3A
85
What are the phase 1 reactions
Oxidations (CYP dependent and independent)
Reduction
Hydrolysis
86
What are CYP inducers
They increase the expression of CYP450 enzymes
| Which reduces teh plasma level and effectiveness of the drug
87
What are some examples of CYP inducers
Benzopyrenes in cigaretter smoke
Chronic ethanol
Barbiturates
Carbamazepine
88
What are CYP inhibitors
Decrease the expression of p450 enzymes
Increase the plasma level
Increase risk of toxicity
89
What are some examples of CYP inhibitors
Cimetidine
Erythromycin
Grapefruit juice
90
T/F CYP inducers and inhibitors work after 1 exposure
False
| You need to have regular daily exposure for an extended period of time
91
What are the most important Phase 2 reactions
1. Glucuronidation
2. Sulfation
3. Acetylation
92
What is the most common Phase 2 reaction
Glucuronidation
93
What enzyme is used in glucuronidation
Glucuronosyl transferase
94
What enzyme is used in sulfation
Sulfotransferase
95
What enzyme is used in acetylation
Acetyltransferase
96
What happens in slow acetylators
They are slow metabolizers
Long half life
Can get Lupus
97
What happens in fast acetylators
Fast metabolism
Have a lot of drug
Short half life
98
T/F elimination and excretion are the same thing
FALSE
99
What occurs in glomerular filtration
Only free unbound drug is filtered
100
What occurs in the PCT
Secretion
OAT and OBTs
There is competition between drugs for carriers
101
What happens in DCT
Reabsorption
102
Weak acid overdose, give:
Bicarbonate
103
Weak base OD, give:
Ammonium chloride
104
There are many modes of excretion
Know this
105
First order kinetics
Constant fraction
Half life is constant
Non saturating kinetics
106
Zero order kinetics
Constant amount
Half life is not constant
Saturating kinetics
107
What are the zero order drugs
High doses of aspirin
Ethanol
Phenytoin
108
How is half life determined
Volume of distribution and CLearance
109
Maintenance dose is used for what conditions
Chronic
110
Loading doses are used for what conditions
Acute
111
How do you pick a drug dose
1. Pick target plasma level
2. Compute dose
3. Measure plasma level
4. Adjust dose
112
What does a maintenance dose do
Maintain the steady state or target concentration of a drug
113
What is a loading dose
Given in one or a series of doses to achieve a target concentration rapidly
114
What is the loading dose equation?
LD: CSS x d/F
115
If the time to reach steady state is long, should you use a LD or a MD?
LD
116
What is a steady state?
The goal concentration you want to reach with a drug.
117
The time that it takes to reach steady state for a drug eliminated by first order kinetics is a function that drugs what?
Half life
118
What is the clinical steady state
4-5 half lives
119
What is the mathematical steady state
10 half lives
120
T/F the half life of a drug is unaffected by the amount of drug given either by constant infusion, single injections, or orally, as long as the drug is eliminate by 1st order kinetics
True
121
Are there oscillations around steady state with continuous infusion?
No
122
Are there oscillations around steady state with single or multiple doses
Yes
123
The peaks of a half life diagram should always be above or below what?
Below Minimum toxic concentration
124
What should troughs of half life diagram always be above or below
Above MEC
125
What makes up the therapeutic window?
The MTC and MEC
126
What is the normal creatinine clearance
100 mL/min
127
What is the renal CL equation
CD: average dose x (patients Cre CL/100 mL/min)
