General Principles of Pharacology Flashcards
1
Q
name 3 physiochemical properties of drugs
A
molecular size
fat/water solubility
ionic charge
2
Q
what determines the degree of fat and water solubility of drug
A
polarity of drug
3
Q
what determines ionic charge of drug
A
acidic basic neutral nature of drug
4
Q
how is molecular size determined
A
number and type of atoms in molecule
arrangement of molecules (sterochemistry)
5
Q
Why is molecular size important for drug
A
determine whether it passes through pores or between cells
6
Q
Adding what type of element makes molecules bigger
A
halogens
7
Q
why is solubility important for a drug
A
determines if drug stays in plasma or penetrates tissue
8
Q
what type of molecule makes a drug polar
A
ionizing
9
Q
how is solubility measured
A
partition coefficient (P.C.)
10
Q
formula for partition coefficient (P.C.)
A
[drug]fat/[drug]water
11
Q
what does P.C. >1 mean
A
lipophilic
hydrophobic
12
Q
P.C. Less than 1
A
hydrophillic
13
Q
define acids ( weak/strong)
A
proton donor
14
Q
for weakly acidic drugs, what are characteristics of its conjugate base
A
polar hydrophilic in plasma
15
Q
characteristics of weakly acid drug
A
lipophillic in tissue
16
Q
define base
A
proton acceptor
17
Q
characteristics of weakly basic drugs
A
lipophillic in tissue
many amines
18
Q
for weakly basic drugs, what are characteristics of its conjugate acid
A
stay in plasma
19
Q
define neutral compounds
A
neither donates or accepts protons
20
Q
what are two categories of neutral durgs
A
charged and uncharged
21
Q
neuromuscular blocking drugs are what type of drugs
A
neutral charged
22
Q
neuromuscular blocking drugs characteristics and how is it usually adminstered
A
IV
23
Q
quaternary ammonium is what type of drug
A
neutral charge
24
Q
carboxylic acid contributes to becoming what type of drug
A
acidic groups
25
amines contributes to becoming what type of durg
basic groups
26
what is so special about categorizing amino acids
they have both amine and carboxylic acid
27
alcohols, aldehydes, amides, esters are in what group
neutral uncharged
28
Henderson-Hasselbach equation determines what in drug
if drug is going to be ionized or unionized in its form
| -whether it not it crosses barrier
29
equation for Henderson-Hasselback for weak acid
pH = pKa + log (base)/(acid)
30
A-
base form of weakly acidic drug
31
HA
acid form of weakly acidic drug
32
equation Henderson-Hasselback for weak base
pH = pKb + log (acid)/(base)
33
B
base form of weakly base drug
34
BH+
acid form of weakly basic drug
35
Name 4 ways drugs cross biological membranes
filtration through pores
passive diffusion
active transport
endocystosis
36
name 2 types of passive difusion
simple
| carrier
37
how do most uncharged drugs cross the membrane
passive diffusion
38
how do most charged drugs cross the membrane
active transport
39
driving force for filtration through pores
pressure gradient
40
what is the rate of filtration through pores dependent on
pressure gradient
| size of particle
41
what provides the pressure gradient for filtration through pores
heart contraction
42
active transport requires what
cellular energy
43
active transport can transport across what gradient
low to high
| against [] gradient
44
what determines the rate of drug transport by active transportation? what does this cause?
1. binding capacity of drug species with carrier
2. limited availability of drug
- causes competition
45
drug molecule must have what characteristic in order to move by active transport
full positive or full negative charge
46
passive (non-ionic) diffusion occurs in what direction?
high to low
| proportion to physical force provided
47
when drugs cross membrane with passive (non-ionic) diffusion what characteristics must the drug have
dissolve in aq. solution
| dissolve in lipid membrane
48
how do neutral uncharged drugs go though membrane
maybe pores
no active transport
maybe passively diffuse
49
how do neutral charged drugs go though membrane
maybe pores
maybe active transport ( permanent cations)
no passive difusion
50
how do acid form of weakly acid drugs pass
maybe pores
no active transport
maybe passive diffusion
51
how does base form of weakly acid drug pass
```
maybe pores
active transport (anionic)
no passive
```
52
base form of weak base how does it pass membrane
maybe pores
no active
maybe passive
53
acid form of weak base, how does it cross membrane
maybe pores
maybe active (cationic)
little or no diffusion
54
name 3 routes of enteral administration
oral (p.o)
sublingual
rectal
55
define absorption
getting drug into blood stream
56
define distribution
getting blood out of blood stream and into tissue
57
define excretion
get drug out of body
58
define elimination
drug biologically inactive, but does not leave the body
59
what are the 3 main routes for administartion
enteral
parenteral
topical
60
enteral administration
placement of drugs into GI tract
61
parenteral adminstration
place drug into body other than GI tract
62
topical administration
place drug on surface of tissue
63
where does absorption occur for oral adminstation
stomach
| small intestines
64
during oral administration, absorption occurs primarily through what type of diffusion
passive
65
during oral administration, rate of absorption depends on
rate of dissolution
PC of drug
chemical nature
66
during oral administration, drugs stay longer in what part of the GI tract, why
small intestines
| larger surface area
67
where do drugs go after GI tract via?
liver
| portal system
68
first pass elimination effect
extensive hepatic clearance via biotransformation
69
sublingual
drugs go under tongue
70
sublingual transmission, how are drugs diffused
passive
71
what type of drug usually uses sublingual administration
nitroglycerine
72
during sublingual administration, where does drug enter
general circulation then liver
73
what limits the use for sublingual adminstration
bad taste
74
during rectal administration, how is drug diffused
passive
75
during rectal administration, where does drug enter
general circulation then liver
76
rectal administration is good for what type of patients
unconscious or vomiting patients
77
diffusion form GI to blood, neutral uncharged drugs, rate of diffusion depends on
partition coefficient
78
diffusion form GI to blood, neutral charged drug
low partition coefficient
| little or no diffusion
79
diffusion form GI to blood, weakly acidic drugs
uncharged most likely to diffuse
80
diffusion form GI to blood, weakly basic drugs
uncharged most likely to diffuse
| not readily absorbed in stomach, increase pH in small intestines--> absorbed
81
ion trapping, give example
inject drug IV,
| drug will be found in stomach
82
name 6 ways parenteral administration is done
```
subcutaneous
intramuscluar
intravenous
intraarterial
inhalation
intrathecal
```
83
where are drugs placed for subcutaneous
directly under skin
84
what type of absorption for subcutaneos
passive diffusion though capillary membrane
85
subcutaneous, rate of absorption
blood flow at injection site
86
intramuscular as same characteristics as what other administration
subcutaneous
87
what is the difference between intramuscular and subcutaneous
intramuscluar: uses larger volume
| can use more irritating drugs
88
intramuscular is good for what type of drugs?
| example
```
orally labile ( easily changed) drugs
insulin
```
89
intramscular injections have depot preparations?
drug releases its active compound in a consistent way over a long period of time.
90
for intravenous, where does drug go directly into
blood
91
what is the advantage for intravanous administration
rapid onset
known amount of drug delivered
good for emergency situations
92
what is the disadvantage for intravenous administration
cannot redraw drug
| cannot retard absorption
93
intraaterial , where is drug directly placed
into artery leading to specific organ or tissue
94
what is a benefit for using intraaterial
high [drug] into one body site
95
intraarterial is used with what patients
cancer chemotherapy
96
inhalation is primarily used for
anesthetic/analgesic gases
97
inhalation h as what type of absoprtion
passive
98
for intrathecal where does injection occur into
spinal subarachnoid space
99
what is intrathecal used for
spinal anesthesia
| CNS chemotherapy
100
what are 3 topical administration types
patches
dermatological and opthalmic
intravaginal
101
dermatological and ophthalmic application ....
| intravaginal application deals with what
not absorption but deals with infection on surface
102
the first critical step for drugs is absorption, what is the second critical step
getting drug out of blood stream to sight of action
103
name 5 factors that influence drug distrubution
```
physiochemical
biological membranes
protein binding
blood perfusing
disease states
```
104
what is the first barrier of drug distrubtion
capillary endothelial membrane
105
name 2 locations for special capillary beds
kidney: glomerulus
liver: lack complete endothelial cell lining
106
what is the difference between water soluble and lipid soluble drugs entering cell
only lipid soluble enters
107
how do drugs cross the BBB
passive diffusion
108
BBB have what type of barrier
tight junctions between brain capillary endothelial cells
109
how and where do drugs enter CSF
passive diffusion - ventricles
| active transport - choroid plexus
110
fetal barrier - placenta have similar characteristics to what
capillary beds
111
do drugs enter the placenta
most drugs yes
112
what is pH of prostate fluid
acidic 6.4 compared to plasma
113
how do drugs enter prostate, what happens to them
passive diffusion
| protonated (ionized), ionic form of basic drug can't diffuse out, ion trapping
114
what is the blood supply to prostate gland compared to other organs
low
115
where does protein occur
plasma
| tissue
116
what is the strongest bond type for protein binding
covalent, may be irreversible
117
compared to proteins, drugs are pharmacologically active when
free in plasma, not bound to protein
118
what is therapeutic index
more likely the drug is free in plasma
119
common protein drugs attach to
albumin
120
lipid soluble drugs can be stored where
fat
121
what is the blood supply to fat
poor
122
what drug and metal gets stored in bones
tetracycline
| lead
123
where can drugs get stored in non-target tissue
kidney
124
what can redistribution of drugs do
terminate pharmacological action of drugs, especially lipophilic drugs
125
initial distribution of drug depends on
blood flow to a body region
126
what does redistribution depend on
other factors other than blood flow
