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SRNAPharmacology II > Pharmacodynamics/Pharmacokinetics > Flashcards

Pharmacodynamics/Pharmacokinetics Flashcards

1
Q

Define Pharmacokinetics

A

The quantitative study of absorption, distribution, metabolism, and excretion of drugs and their
metabolites.

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2
Q

4 processes studied by Pharmacokinetics

A

Absorption
Distribution
Metabolism
Excretion

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3
Q

“What the body does to a drug”

A

Pharmacokinetics

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4
Q

Pharmacokinetics allows the clinician to predict the drug ____________and thus the ____________ with time.

A

concentration at the site of action; intensity of the drug’s effect

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5
Q

Pharmacokinetics measures and calculates those parameters

A 
VECBECR
Volume of Distribution
Effect site equilibration time(onset of action once med is given)
Context sensitive half life (lipid soluble drug)
Bioavailability
Elimination half life
Clearance
Recovery time
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6
Q

Cell membrane and lipid soluble substances

A

Highly permeable

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7
Q

Since the cell is also permeable to water and other small lipid in-soluble substances it is postulated that the lipid membrane

A

has channels or pores that allow these substances to penetrate the cell.

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8
Q

• Simple diffusion Definition- characterized by the

rate of _________ both _____and _____of small size

A

transfer of a substance across a membrane from area of high concentration to an area of low concentration. Both lipid soluble and lipid in-soluble molecules of small size.

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9
Q

• Filtration-

A

When a porous membrane allows the flow of a solvent and the substances dissolved in it to except for large molecules (ex. glomerular filtration).

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10
Q

Most of the drugs given in anesthesia are

supplied in the form of a_________

A

salt solution.

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11
Q

• The active molecule of anesthesia is either a

A

weak acid or weak base.

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12
Q

• The active portion can be recognized as an

acid or a base by the

A

name given to the salt form.

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13
Q

 If the active moiety is an acid, the acid
is listed
 If the active moiety is a base, the base
will be listed

A

last (sodium thiopental)

first (Lidocaine HCl,
Morphine Sulfate)

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14
Q

• Acids (donate or accept protons)

A

donate protons

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15
Q

Bases (donate or accept protons)

A

accept protons

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16
Q

Henderson-Hasselbach equation

A

pH = pKa + log Proton acceptor/ Proton donor

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17
Q

Cell membranes are more permeable to which portion of a drug?

A

non-ionized portion of a drug.

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18
Q

The Henderson-Hasselbach equation helps to predict _____________Given the ________of that particular solution and the drugs ____

A

the portion of ionization of a given drug in solution given the pH of that particular solution and the drugs pKa

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19
Q

When pH=pKa, what can be infered?

A

50% of the drug is ionized and 50% in non- ionized.

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20
Q

Lower pKa= ______acid

A

stronger acid,

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21
Q

Higher pKa = ________base

A

stronger base.

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22
Q

A general rule with WEAK BASES states when the pKa minus pH < 0, then most of the drug will be in the

A

non-ionized form.

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23
Q

With WEAK ACIDS, the opposite is true. pKa minus pH < 0 then most of the drug will be in the

A

Ionized form

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24
Q

Weak acids will be more non-ionized in an ________therefore ________ is better

A 
acidic solution (absorption,
distribution).
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25
Q

Weak bases will be more non-ionized in a

Can therefore penetrate

A

basic solution.; blood brain barrier, renal tubular epithelium, GI epithelium, and hepatocytes

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26
Q

Define Ion Trapping?
Example?
Fetus is more acidic/basic than mother

A

A concentration difference of total drug can develop on two sides of a membrane that separates fluids with a different pH.
obstetrics when the administration of an epidural such as
local anesthetic can accumulate or become trapped in the fetus because the fetus is more acidic than the mother. This can lead to fetal toxicity.

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27
Q

How do you eliminate acidic drugs from the body?

A

Alkalinize the urine to help eliminate acidic drugs.

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28
Q

Define active transport? Requires ? Example is

A

With active transport a substances moves against a concentration or electrochemical gradient. Usually requires the use of energy by the cell.
Na-K pump

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29
Q

Define volume of distribution ? *(Vd)

A

• Calculated as the dose of drug administered IV divided by the resulting plasma concentration BEFORE ELIMINATION BEGINS

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30
Q

Vd is Influenced by physiochemical characteristics

of the drug (3)

A

Lipid solubility
Protein binding
Molecular size.

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31
Q

Drug with low lipid solubility and high protein binding will have a__________

A

low Vd.

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32
Q

What can be used to predict the plasma drug concentration after a bolus?

A

The volume of distribution

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33
Q

Question #1
“what is the predicted gentamicin concentration 30 minutes after 200mg of gentamicin is administered to a 70kg patient.” If the Vd of gentamicin is 0.28 L/Kg in adult

A

calculate

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34
Q

Question #2
“what dose of gentamicin is needed
to achieve a plasma concentration of 5 in a 3 Kg
neonate. “ The Vd in neonates is 0.5 L/Kg

A

Calculate

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35
Q

Most acidic drug bind to _______

A

Albumin

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36
Q

Most basic drug bind to_________

A

alpha 1 acidic protein.

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37
Q

Why does protein binding effects Vd?

A

because only unbound drug can cross cell membranes.

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38
Q

Relationship between Vd and protein binding?

A

Inversely proportional

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39
Q

Protein binding also effects clearance.

A

Clearance. Because only unbound drug can undergo metabolism and GLOMERULAR FILTRATION

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40
Q

Alterations in protein binding are only important for drugs that are

A

highly protein bound.

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41
Q

4 well known highly protein bound drugs

A

Warfarin
Phenytoin
Diazepam
Propranolol

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42
Q

The extent of protein binding is directly related to the______ _______

A

lipid solubility

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43
Q

In addition the fraction of total drug in plasma that is bound to protein is determined by (2)

A

 Plasma concentration of drug

 The number of protein binding sites

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44
Q

•___________ plasma concentration of drug will be highly protein bound compared to high plasma concentrations of the same drug.

A

Low plasma concentration

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45
Q

Can cause low concentrations of plasma proteins.

A

Renal Failure

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46
Q

Increased levels of Alpha 1 acid glycoprotein can occur in response to (3)

A

surgery, chronic pain, and acute MI.

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47
Q

_______can be low in neonates.

A

Alpha 1 acid glycoprotein

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48
Q

What is clearance ?

A

The volume of plasma cleared of drug by renal excretion and/or metabolism by the liver or other organs

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49
Q

Examples of non-organ metabolism include

2 processes: 4 meds examples

A

Hoffman elimination
Ester hydrolysis of succinylcholine,
atracurium, cisatracurium, and
mivacurium SAM-C

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50
Q

Define first order kinetics

A

Almost all drugs are cleared from the circulation at a rate that is proportional to the amount the amount present in plasma

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51
Q

Zero Order Kinetics

A

A constant amount of drug in cleared per unit of time.

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52
Q

In order to achieve steady state, the infusion rate must be equal to the

A

clearance.

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53
Q

Hepatic clearance is the the product of

A

hepatic blood flow and the hepatic extraction ratio.

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54
Q

If the hepatic extraction ratio is high >0.7, then

A

the hepatic clearance will depend on hepatic blood flow and changes in enzyme activity will have minimal change

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55
Q

Thus a high hepatic extraction ration results in a_________ example

A

perfusion-dependent elimination

Lidocaine

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56
Q

If the extraction ratio is <0.3 than the clearance will depend on

A

protein binding and enzyme activity

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57
Q

Most important organs for the elimination of unchanged drugs.

A

Kidneys

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58
Q

Renal excretion includes 3 processes;

A

 Glomerular filtration.
 Passive tubular secretion.
 Passive tubular reabsorption

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59
Q

The amount of drug that enters the renal tubular lumen depends upon 2 things:

A

 Fraction of protein binding and the

glomerular filtration rate.

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60
Q

Renal tubular secretion involves.

A

active transport processes.

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61
Q

• Highly lipid soluble compounds are almost

A

completely reabsorbed.

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62
Q

• Factors that effect reabsorption include;

A

 pH (weak acids are excreted faster in alkaline
urine)
 Rate of tubular urine flow

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63
Q

Formulas to use to estimate creatinine clearance

A

IBW male 50 +(2.3 x each inch >60) IBW in Kg

IBW female 45.5 + (2.3 x each inch >60) = IBW in Kg

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64
Q

Cockcroft-Gault equation

A

• (140 - age ) x IBW 72 x Serum creatinine x 0.85 for females.

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65
Q

Local anesthetics work on

A

sodium channels.

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66
Q

The role of metabolism is to

A

convert pharmacologically active, lipid-soluble drugs
into water soluble inactive compounds that
can be easily excreted.

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67
Q

Increased water solubility will _________Vd

for a drug and enhance its renal excretion.

A

decrease

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68
Q

• These compounds are called prodrugs.

A

The metabolism of an inactive compound to
a pharmacologically active compound can
also occur

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69
Q

The metabolism of a drug is highest when

A

the drug concentration is greatest.

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70
Q

Drug name first (base or acid)

A

base

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71
Q

The fraction of drug eliminated is independent of the drug concentration

A

First order kinetics

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72
Q

It will take 1 half-life for the plasma
concentration to decline
•

A

by 50%.

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73
Q

At 5 half-lives the drug plasma concentration declines by

A

96.9 %

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74
Q

Constant amount of drug is eliminated per unit of time

A

irregardless of the plasma concentration.

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75
Q

Zero order Occurs when the plasma concentration of

drug exceeds

A

the capacity of metabolizing enzymes

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76
Q

When inject basic to acidic

A

Precipitate

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77
Q

Drugs that undergo zero-order kinetics include

A

alcohol, aspirin, and phenytoin

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78
Q

Oxidation-

Reduction-

A

Loss of electrons

Gain of electrons

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79
Q

• Hydrolysis definition

A

Splitting molecule with the addition of water.

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80
Q

______,______,_____ are

Phase I reactions

A

Oxidation, reduction and hydrolysis

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81
Q

Conjugation-Phase II reaction.

A

The addition of an endogenous substrate such
as a carbohydrate or an amino-acid to form
a more water soluble, inactive substance
that is easily excreted from the body.

82
Q

____________is the site of metabolism of most drugs.

• Other sites include the GI tract, kidneys, and the lungs

A

Hepatic microsomal enzymes

83
Q

________is site for Hoffman degradation or ester hydrolysis

A

Plasma ; spontaneous degradation

84
Q

Plasma is site for

A

Hoffman degradation or ester hydrolysis

85
Q

Location of hepatic microsomal enzymes

A

Located primarily in the smooth endoplasmic reticulum of the liver

86
Q

Cytochrome P-450 also called_________ system involves both __________steps.

A

mixed function oxidase

oxidative and reduction

87
Q

Cytochrome P-450 is available in different
isoenzymes P-450______ is the most
abundant

A

3A4

88
Q

Cytochrome P-450 3A4 is responsible for metabolizing more than 1/2 known drugs including

A

opiods, benzodiazepines, local anesthetics, immunosuppressants.

89
Q

• Alfentanil clearance has been shown

A

to vary on different days of the menstrual cycle

90
Q

Enzyme induction

A

• Drugs or chemicals have the ability to stimulate the activity of microsomal enzymes.

91
Q

• Increased enzyme activity by certain compounds is known as_______

A

enzyme induction.

92
Q

• Compounds known to stimulate enzyme

induction include, RPPCSC

A

Phenobarbital, phenytoin,
alcohol, cigarette smoking, rifampin,
carbamazepine.

93
Q

Enzyme Inhibition

A

• When the metabolic rate of the microzomal enzymes is decreased leading to drug accumulation and possible toxicity.

94
Q

Enzyme inhibitors include.

A 
 Acute alcohol ingestion
 Cimetidine Erythromycin
 Valproic acid
 Nefazodone
 Fluoxetine
 Amiodarone
 diltiazem, verapamil
 Protease inhibitors
95
Q

**Nonspecific esterases in the liver, plasma, and
GI tract are examples on nonmicrosomal enzymes responsible for
SAMEE

A

hydrolysis of drugs that contain ester bonds

SUCCINYLCHOLINE, atracurium, mivacurium, ESMOLOL, ester local anesthetics.

96
Q

The activity of these enzymes is determined

genetically, as emphasized by patients with

A

atypical cholinesterase, and slow acetylators

97
Q

Nonmicrosomal enzymes such as______and______ do not undergo enzyme induction.

A

plasma cholinesterase and acetylating enzymes

98
Q

Oxidative metabolism: Halogenated volatile anesthetics are susceptible to dehalogenation, which can lead to the release of

A

bromide, chlorine, and fluoride ions.

99
Q

Enzyme induction and depletion of glutathione can increase

A

risk or organ damage.

100
Q

Conjugation
• Conjugation with glucuronic acid involves_______ Glucoronic acid is available from glucose.
•

A

CYP-450 enzymes.
Glucose
This leads to the the formation of inactive water soluble compounds which are inactive and easily excreted from the body.
• Conjugation may be decrease during pregnancy due to increase levels of progesterone.

101
Q

Factors that effect Vd and Clearance

A

Metabolism
Age
Hepatic disease
Kidney disease

102
Q

Two compartment model

Central compartment

A

The drug is introduced directly into the central compartment then subsequently distributes to the peripheral compartment only to return to the central compartment where clearance occurs.

103
Q

• Central compartment includes intravascular

fluid and highly perfused organs

A

(lungs, heart, brain, kidneys, liver).

104
Q

• In adults highly perfused tissues make up of ____weight, but receive______ of cardiac
output.

A

10% ; 75%

105
Q

• Drugs that have an affinity for the vessel

poor group have

A

higher volumes of distribution.

106
Q

• Vessel poor group

•

A

(Muscles, fat, skin, etc)

107
Q

FIRST ORDER KINETICS DRUGS

A

Vd works better

108
Q

A large calculated peripheral compartment

suggest

A

extensive uptake of drug by those
tissues that make up the peripheral
compartment.

109
Q

Redistribution

A

The drug distributes from it’s site of action to other tissues. (ex, thiopental)

110
Q

New Concepts in interpretation of compartment modeling
• Rapid IV injection of drugs that attain
maximum effect in <2 minutes such as ___and____
• These drugs do not depend on the usual
organs for elimination. They are eliminated
by.

A

(atracurium, cisatracurium).

Hoffman degradation, and hydrolysis

111
Q

The traditional concept that a drug’s pharmacological effect parallels its plasmas concentration is not
• For example 1 minute after the IV bolus of
cisatracurium the plasma concentration is

A

always valid
already declining while the pharmacological
effect is increasing.

112
Q

The traditional concept of the drug’s pharmacological effect is parallel to plasma concentration is no longer valid. Therefore it is proposed that it is not the concentration in the _______Compartment but the concentration at ________that determines the pharmacological effect.

A

concentration in the central compartment but the concentration at the site of action that determines the pharmacological effect

113
Q

Elimination half time is the time necessary

for

A

the plasma concentration to fall by 50% during the ELIMINATION phase.

114
Q

• Elimination half-time is _______related to and__________ to clearance.

A

directly; Vd; inversely related to

115
Q

• Elimination half time is unrelated to the

A

dose given

116
Q

It take about_________for near total

(96.5%) elimination from the body

A

five t -1/2

117
Q

Formula for half life

A

T1/2= 0.693/ke

118
Q

ke can be calculated by checking

A

2 plasma drug concentrations after a single IV bolus

119
Q

Elimination half time may be of little value

in describing drug

A

Pharmacokinetics in multicompartment models

120
Q

Of more importance to the clinician is how
long will it take the Cp to decrease to allow
the patient to

A

awaken, rather than the slope of the plasma drug concentration time curve.

121
Q

• Instead of t-1/2 the clinician should use the

A

context sensitive half time

122
Q

Context Sensitive half life Describes the time necessary for the plasma concentration to

A

decrease by 50% after discontinuing a continuous infusion of a specific duration.

123
Q

Context sensitive half life consider both___

A

combined effects of distribution and metabolism as well as duration of continuous infusion.

124
Q

Depending on the_________and __________ the context sensitive t-1/2 as the duration of
the infusion increases

A

lipid solubility and the efficiency of its clearance,

increases

125
Q

Effect-Site Equilibration

A

The delay between the IV administration of a drug and the onset of its clinical effects.

126
Q

• Reflects time required to deliver the drug

to its site of action (ex. Brain).

A

Effect site equilibration

127
Q

Drugs with a short effect site equilibration
such as ______, ______and______
will produce a ______onset of action.

A

remifentanyl, thiopental, propofol, TEP

rapid

128
Q

Drugs with a longer effect site
equilibration ______and ______have a
onset of action.

A

, midazolam, fentanyl; slower

129
Q

2 things affecting absorption

A

Blood flow

Surface area

130
Q

Oral route advantage, principal site of absorption.

Disadvantages

A

Most economical and convenient
Principal site of absorption is the SMALL intestine

EMEsis, Destruction by digestive enzymes or gastric acid.

131
Q

Drugs absorbed from GI tract enter the.

This is known as

A

portal venous blood and pass through the liver prior to entering systemic circulation
first pass hepatic effect.

132
Q

• Drugs that undergo large first pass hepatic effect have large differences in pharmacological effect between IV and PO routes of administration. EX

A

(lidocaine, propranolol)

133
Q

Zero order kinetics

A

Specific number of molecules removed, REGARDLESS of the dose given

134
Q

Oral Transmucosal route
3 advantages
What does it bypass?

A

Permits rapid onset of action.
• Venous drainage into the superior vena cava bypasses the liver and avoids first pass effect.
• Explains why sublingual NTG is more effective than PO NTG.

135
Q

Which route provides sustained therapeutic plasma
concentration.

• Examples of drugs available as transdermal
patch include;

A

Transdermal route

NTG, clonidine, fentanyl,
scopolamine, estrogen, nicotine

136
Q

Characteristics of a drug that favors

transdermal administration include;

A 
 Combined water and lipid solubility
 Molecular weight < 1,000
 pH 5-9 in a saturated aqueous solution
 absence of histamine release
 Daily dosing requirements < 10mg
137
Q

Rectal : Drugs administered to_________

avoid the first pass effect.

A

lower rectum

138
Q

Drugs administered into the________ _____are absorbed into the superior _______ _____and are transported to the liver, hence first pass effect.

A

proximal rectum ; hemorrhoidal veins

139
Q

Most rapid and predictable route

A

IV

140
Q 
Only acceptable route in the
unconscious and uncooperative
patient.
• More expensive
• Most risky
A

IV

141
Q 
Distribution of drugs after systemic
absorption Explain
What happens after systemic absorption?
What happen to plasma concentration?, what happen?
Redistribution depends on what factors?
A

After systemic absorption , the highly perfused tissues (heart, brain, kidneys, liver) receive a disproportionately large amount of the total dose.
• As plasma concentration falls below that achieved in highly perfused tissues, the drug redistributes to less well perfused sites such as skeletal muscle and fat.
• Redistribution depends on blood flow, concentration gradient for non-ionized, lipid soluble, and unbound to protein portion

142
Q

If drugs can access brain

A

Has to be lipid soluble

143
Q

Redistribution concept explain
Tissue does what?
Repeated dose lead to
Drugs example?

A

A tissue that accumulates drug can act as a reservoir to maintain the drug concentration in the systemic circulation and prolong its duration of action.
• Repeated dosing or large doses may saturate inactive tissue sites and prevent the drug from distributing into inactive sites and thus prolong the duration of
action.
• This can occur with drugs such as fentanyl
or thiopental.
• Waning of drug effects now depend on metabolism rather than redistribution

144
Q

Uptake into lungs

A

Basic lipophilic amines such as lidocaine, meperidine, fentanyl sufentanil, and alfentanil will quickly distribute to the lungs were they are inactive.
• Pulmonary uptake of drugs can influencethe peak arterial concentration and serve
as a depot for drug redistribution

145
Q

Pulmonary uptake of drugs can influence the

A

peak arterial concentration and serve as a depot for drug redistribution

146
Q

Blood brain barrier

• Prevents

A

distribution of ionized water soluble drugs to the CNS

147
Q

Pharmacodynamics simple

A

“What the drug does to the body

”

148
Q

Pharmacodynamics definition

A

study of the intrinsic sensitivity of responsiveness of receptors to a drug and the mechanism by which these effects occur.

149
Q

Isomers are

A

different compounds that have the same molecular formula.

150
Q

Sterioisomers -

A

are a particular kind of isomer that are different from each other only in the way the atoms are oriented in
space (but are like one another with
respect to which atoms are joined to which
other atoms)

151
Q

Enantiomers

A

A pair of molecules existing in two forms
that are mirror images of one another but
cannot be superimposed.

152
Q

Enantiomers that are dissolved in solution,
can be distinguished
–

A

by the direction that rotate polarized light.

153
Q

– (d or +) rotate light to the

A

right

154
Q

(l or -) rotate light to the

A

left

155
Q

When two enantiomers are present in

A

equal
proportions (50:50), they are referred to as
a racemic mixture.

156
Q

A racemic mixture (does/does not) rotate polarized light.

A

does not

157
Q

Heparin PTT Drawn after 6 hours because

A

by that time, 5 half lives (steady state to occur)

158
Q

Lock and Key Emphasizes the fact that

A

biological systems are inherently steriospecific.

159
Q

Factors that effect the phamacodynamics of a drug

•CRC PAP

A

-Concentration or density of receptors.
- Responsiveness of the receptor.
- Clinical state of the patient;
- Preexisting disease
-Age of the patient
-pH balance effects the degree of
ionization

160
Q

Hyperactive-

A

unusually low doses produces desired effect

161
Q

• Hypersensitive-

A

Term used to describe patients that are allergic (sensitive) to a drug

162
Q

• Hyporeactive-

A

patients that require unusually high doses to evoke a desired effect.

163
Q

• Tolerance-describes

A

hyporeactivity that is

acquired from chronic exposure to a drug

164
Q

• Tachyphylaxis is

A

tolerance that develops

after a few doses or short period of time.

165
Q

An additive effect-

A

a second acting with the first drug will produce an effect equal to an algebraic summation (1+1=2)

166
Q

Synergistic effect-

A

The two drugs interact to produce an effect that is greater than the algebraic summation (1+1=4)

167
Q

• Agonist-

A

a drug that activates a receptor by binding to it

168
Q

• Antagonist-

A

A drug that binds to receptor but does not activate the receptor and blocks any activation of that receptor.

169
Q

Dose response curve

A

Show the relationship between the dose of a drug and the resulting pharmacological response

170
Q

Morphine 6 glucorinide

A

More active than parent compound morphine itself

171
Q

Dose response curves are characterized by differences in (PIES)

A

potency,
individual response
efficacy
slope,

172
Q

The potency of a drug is depicted by its

A

location along the dose axis of the dose response curve

173
Q

Factors that effect potency include

ADME + A

A

Absorption, distribution, metabolism, excretion, and affinity for the receptor sites

174
Q

Potency has no real clinical difference as

long as the the

A

effective dose can be achieved.

175
Q

The slope is influenced by

A

the number of receptors that must be occupied to have a certain effect.

176
Q

______And ________are characterized by a steep
dose response curve.
• Small increases in dose will have a

A

Neuromuscular blockers and inhaled
anesthetics
dramatic increase in effects.

177
Q

• An increase from 1 MAC to 1.3 MAC will

prevents movement in skeletal muscle from

A

50% of patients to 95% of patients

178
Q

Efficacy
• Side effects may limit the dosage to below
the concentration associated with maximal
desirable effects.

A

• The efficacy is depicted by the plateau in dose response curve.

179
Q

• Therapeutic index-

A

the difference between the the dose that produces the
desired effect and dose that produces undesirable effects.
• LD50/ED50

180
Q

Competitive antagonist-

A

increasing concentrations of antagonist progressively inhibits the response to an unchanging concentration of
agonist.

181
Q

Noncompetitive antagonist

A

Even high concentrations of agonist cannot overcome blockade of the antagonist

182
Q

Events that determine variation in
drug response
• Pharmacokinetics

A 
 Bioavailability
 Renal function
 Hepatic function
 Cardiac function
 Patient Age
183
Q

Events that determine variation in
drug response
Pharmacodynamics

A

Pharcodynamics
 Enzyme activity
 genetic difference
• Drug interactions

184
Q

Elderly patients have those

A 
Decreased cardiac output
Enlarged fat content
decreased protein binding, 
decreased renal function 
all lead to drug accumulation and
increased risk of toxicity
185
Q

Can effect the individual response curve

 G6PD deficiency certain drugs can cause
hemolysis (Isoniazid)

A

Genetic disorders

186
Q

 Atypical pseudocholinesterase patients lack

A

the enzyme that breaks down NMB agents

187
Q

 Malignant hyperthermia produces a

A

devastating hypermetabolism

188
Q

Intermittent porphyria evoked by

A

barbiturates purple urine

189
Q

 G6PD deficiency certain drugs can cause

A

hemolysis (Isoniazid)

190
Q

Drug interactions

•

A 
Impaired absorption
Competition for plasma binding sites
Enzyme induction and inhibition
Change in rate of renal excretion 
     (Example probenacid and PCN)
191
Q

Van der Waals forces-

A

weakest type of bond between atoms or groups of atoms.

192
Q

Hydrogen bonds-

A

occur between hyproxyl or amino groups and electronegative carboxyl oxygen.

193
Q

Covalent bonds-

A

Sharing of pair of electrons (strongest and hardest bond to break)

194
Q

Ionic bond-

A

bond between groups of oppositely charged molecules

195
Q

Plasma drug concentration
•
•

A

Clearance rate must match infusion rate to maintain plasma steady state.

196
Q

• Changes in Vd will necessitate an

A

increase or decrease of initial loading dose

197
Q

________ and __________is
a method to obtain therapeutic levels
quickly and steady state quickly

A

Loading dose and maintenance dose

198
Q

Weak ACID pHpKa what form?

A

Non-ionized (lipid soluble)

Ionized (water soluble)

199
Q

Weak BASE pHpKa what form?

A

Ionized (water soluble)

Non-Ionized (lipid soluble)

200
Q

What form readily cross membrane

A

Non-ionized (lipid soluble)

201
Q

2 factors context sensitive half life take into considerations

A

Clearance and volume of distribution

SRNAPharmacology II (32 decks)

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