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SEE/BOARD STUDY > APEX: PharmacoKinetics > Flashcards

APEX: PharmacoKinetics Flashcards

1
Q

What is the loading dose?

A

The amount of a drug that must be administered to quickly achieve a therapeutic plasma concentration.

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2
Q

The Vd describes what relationship?

A

Relationship between a drug’s plasma concentration following a specific dose. It is a theoretical measure of how a drug distributes throughout the body

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3
Q

What are the 2 things that Vd assumes?

A

The drug distributes instantaneously (Full equilibration occurs at t=0)
The drug is not subject to biotransformation or elimination before it fully distributes.

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4
Q

Vd is a calculated

A

Value and it is something we can directly measures.

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5
Q

Vd formula

A

Vd = amount of drug/ desired plasma concentration

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6
Q

Concentration is a measure of

A

amount per volume

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7
Q

Total body water is

A

42L

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8
Q

Total body water divisions

A

Extracellular 14

Intracellullar 28

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9
Q

Extracellular volume division

A

Plasma volume 4L

Interstitial fluid 10L

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10
Q

A drug with a Vd that exceed total body water

A

> 0.6L/kg or >42L ) is asssumed to be lipophillic.

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11
Q

Lipophillic drug distributes into the

A

Total body water as well as into fat.

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12
Q

Meaning of lipophilic drugs as far as plasma concentration:

A

Higher dose to achieve a given plasma concentration. Propofol has a very large Vd

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13
Q

A drug with a VD less than TBW is assumed to be

A

Hydrophillic.

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14
Q

Hydrophillic drugs does not distribute into _____Therefore_____

A

FAT therefore requires a lower dose to achieve a given plasma concentration.

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15
Q

Example of hydrophillic drugs

A

NMB are restricted to the ECF and have a comparatively small Vd

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16
Q

Vd is affected by what drugs characteristics

A

Molecular size
Ionization
Protein binding
patient characteristics(pregnancy and burns)

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17
Q

The higher the Vd

A

the higher the loading dose must be given to achieve the predetermined plasma concentration.

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18
Q

For an IV mediation, bioavailability equals one since it is

A

injected directly into the bloodstream.

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19
Q

Dose that achieves a given plasma concentration is

A

Dependent on the route of administration.

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20
Q

Clearance is directly proportional to

A

Blood flow to clearing organ

Extraction ratio

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21
Q

What is clearance?

A

volume of plasma that is cleared of drug per unit of time

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22
Q

Clearance relationship to blood flow?

A

Clearance is directional proportional to blood flow to the clearing organ, extraction ratio, and drug dose.

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23
Q

Clearance relationship to drug concentration?

A

CL is inversely proportional to half life and drug concentration on the central compartment.

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24
Q

Cl is directly proportional to (BED)

A

Blood flow to clearing organ
Extraction ratio
Drug dose

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25
Q

What is clearance Cl is inversely proportional to

A

Half life

Drug concentration in the central compartment.

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26
Q

The most important clearing organs are

A

liver
kidney
Organ independent (Hoffman elimination and ester hydrolysis in the plasma)

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27
Q

To maintain a steady state concentration in the plasma,

A

the infusion rate or dosing interval must equal the rate of clearance by metabolism and elimination.

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28
Q

What is vital when calculating a continuous infusion or determining a dosing interval?

A

Clearance.

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29
Q

SS Rate of administration =

A

rate of elimination

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30
Q

What is the definition of steady state

A

When the amount of drug entering the body is equivalent to the amount of drug being eliminated from the body.

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31
Q

Steady state means that there is a

A

Stable plasma concentration.

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32
Q

Each of the compartment has_______When there is steady state.

A

Equillibrate , although the amount of total drug may be different in different compartments.

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33
Q

Steady state is achieved after _____ half times

A

five.

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34
Q

The steepest portion of the curve represents? What phase is that?

A

Redistribution from the plasma to the tissues. THIS IS CALLED THE ALPHA PHASE

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35
Q

The less steep portion of the curve represents

A

Elimination from the plasma. This is called the BETA PHASE

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36
Q

Mnemonic to remember curve dose response

A

D up E dow

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37
Q

The plasma concentration curve graphically depics the

A

Biphasic decrease of a drug’s plasma concentration following a rapid IV bolus.

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38
Q

When we give a rapid bolus , the drug follows it

A

concentraton gradient fromthe central compartment (plasma) to the peripheral compartments (the tissues)

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39
Q

As a general rule, the more lipophillic:

A

the larger the Vd, and the steeper the slope.

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40
Q

As soon as a drug enters the plasma part of it

A

Redistributes based on the concentration gradient between the plasma and the tissues.

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41
Q

At the same time, some of the drugs in the plasma is

A

undergoing elimination

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42
Q

As concentration in the plasma continues to decline as a result of continued elimination, the concentration gradient

A

reverses and drug redistributes from the peripheral compartment and re-enters the central compartment.

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43
Q

The flatter slope (beta phase) represents

A

Drug elimination from the central compartment.

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44
Q

The alpha portion of the curve represents

A

Distribution called also T1/2 alpha

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45
Q

The beta portion of the curve represents

A

Elimination called also T1/2Beta

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46
Q

Rate constants communicate

A

The speed at which a reaction occurs (how fast molecules move between compartments)

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47
Q

K12 is the

A

rate constant for drug transfer from central to peripheral compartment

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48
Q

K21 is the

A

Rate constant for drug transfer from peripheral to central compartment

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49
Q

Ke is the

A

Rate constant for drug elimination from body

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50
Q

The 3 compartment model has multiples

A 
VD
tissue concentration
Rate constants
half lives
clearances.
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51
Q

Elimination half life is the

A

time requires for a drug’s plasma concentration to decline by 50 percent.

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52
Q

After four half lives have elapsed, the patient’s serum will contain

A

6.25 % of the original dose.

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53
Q

Elimination half-LIFE is t

A

the time it takes for 50% of the drug to be removed from the body after a rapid IV injection

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54
Q

Elimination half-TIME is

A

time it takes for 50% of drugs to be removed from the plasma during the elimination phase.

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55
Q

When the rate of a drug removal from the plasma is not the same as the rate of drug removal from the body,

A

the elimination half life and half times will be different.

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56
Q

By convention, we say that a drug has been cleared from the body when

A

96.9% of the dose has been eliminated from the plasma. This occurs after 5 half times.

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57
Q

The half time measures a

A

Constant fraction and not a constant amount. (meaning it takes the same period of time for the plasma concentration of a drug to fall from 200 mg/L to 100mg/L as it does for the same drug to fall from 50mg to 25mg/L

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58
Q

Context sensitive half time takes what into account

A

The duration of the drug administration

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59
Q

Contect sensitive half time is the

A

Time required for the plasma concentration to decline by 50% after the infusion is stopped.

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60
Q

The context sensitive half time for a fentanyl infusion increases as function of

A

how long it was infused.

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61
Q

Explain the context sensitive half time for a fentanyl infusion

A

A longer infusion had more time to fill up the peripheral compartment, therefore more fentanyl has to be eliminated and will have a longer elimination half time.

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62
Q

Context sensitve half time of 3 opiods that are longer

A

Fentanyl
alfentanil
sufentanil

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63
Q

Context sensitve halft time of 1 opioids that is metabolized differently

A

Remifentanil. Even though it is highly lipophillic, it is quickly metabolized by plasma esterases

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64
Q

Context sensitive half time from highest to lowest

A 
FASR
Fentanyl
Alfentanil
Sufentanil
Remifentanil
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65
Q

If you put a strong acid or a strong base in water what will happen?

A

Will ionize completely

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66
Q

If you If you put a weak acid or a weak base in water what will happen?

A

A fraction of it will ionized, and the remaining fraction will be unionized.

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67
Q

Describes the process where a molecure gains a positive or negative charge

A

Ionization

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68
Q

How does ionization affects a molecule?

A

affects molecule’s ability to diffuse through lipid membranes.

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69
Q

The amount of ionization dependent on 2 main things

A

pH of the solution

The pKa of a drug. (dissociation constant)

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70
Q

What happens the pka = pH

A

50% of the drug will be ionized and 50% will be unionized.

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71
Q

Small changes in pH can have a profound impact on

A

the degree of ionization (more pronounce if the pKA and pH ave very close, and less if pKa is very far from the ph)

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72
Q

Explain solubility of ionized molecule with water and lipid?

A

Hydrophillic

Lipophobic

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73
Q

Explain solubility of unionized molecule with water and lipid?

A

Hydrophobil

lipophillic

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74
Q

Explain pharmacologic effect of ionized molecule? inactive vs active

A

Not active

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75
Q

Explain pharmacologic effect of unionized molecule? inactive vs active

A

ACtive

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76
Q

Explain Hepatic biotransformation of ionized molecule?

A

Less likely

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77
Q

Explain Hepatic biotransformation of unionized molecule?

A

more likely

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78
Q

Explain diffuses accross the lipid bilayer of ionized molecule? IONIZED
BBB
GI tract
Placenta

A

No
No
No

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79
Q

Explain diffuses accross the lipid bilayer of ionized molecule? UNIONIZED
BBB
GI tract
Placenta

A

Yes
Yes
Yes

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80
Q

Acidic drug in a basic PH (ionized vs unionized)

A

Ionized

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81
Q

Acidic drugs wants to accept/donate protons

A

Donate

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82
Q

Basic drugs wants to accept/donate protons

A

accepts

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83
Q

The acidic drugs happily donates its protons and will become

A

Ionized.

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84
Q

An acidic drug will be highly _______ in an acidic ph

A

UNIONIZED

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85
Q

The acidic drugs wants to donate protons and the acidic solution

A

Wants to also donate protons. Since there are no protons acceptors, the acidic drugs retains its proton and will remain unionized.

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86
Q

A base in an acidic solution will be highly

A

Ionized

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87
Q

The basic drugs wants to accepts protons and the basic solution

A

Wants to do the same. Since there are no proton donors, the basic drugs will remain unprotonated, and will remain unionized.

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88
Q

Drugs are usually prepared as a

A

salt that dissociated in solution

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89
Q

A weak acid is paired with a

A

Positive ion Cations (sodium, calcium, magnesium)

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90
Q

Sodium thiopental is an example of weak acid or weak base?

A

Weak acid.

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91
Q

With weak acid name that is first is the

A

Cation

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92
Q

A weak base is paried with a

A

Negative ion such as chloride or sulfate

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93
Q

Lidocaine hydrochloride is an examples of weak acid or weak base

A

Weak base.

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94
Q

Which circumstance creates the strongest gradient for passage of LA from the mother to the fetus?

A

Maternal alkalosis

Fetal acidosis

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95
Q

Explain ion trapping of LA in the fetus.

A

Maternal alkalosis : Increases the unionized fraction in the maternal circulation; more LA is available to diffuse accross the placenta.
Fetal acidosis: Increases the ionized fraction inside the fetus. this prevents the LA from crossing the placenta (back to the mother, thus trapping inside the fetus)

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96
Q

Fraction of a drug that will freely diffuse across the cell membrane? after what happens?

A

Unionized fraction. It will ionize according to its pKa and the pH of the solution on this side of the membrane. therefore the drug concentration as well as the degree of ionization will be different on each side.

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97
Q

How to calculate free fraction of protein bound drugs.
If a drug is usually 98% bound by plasma protein and the bound fraction is reduced to 96% , the free fraction wil increase by ?

A

New value - old value / old value x 100

4-2/2 x 100 = 100%

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98
Q

Plasma proteins are synthesized by the

A

liver.

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99
Q

Plasma protieins are

A

too large to pass through the cell membrane and therefore remain confined to the circulation.

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100
Q

The drug and plasma protein form this type of bond

A

weak bond such as an ionic, hydrogen or van de waarls bondd

101
Q

Can a drug bound to plasma protein bind to a receptor?

A

no

102
Q

Only this type of drug form can affect the body

A

released from the protein.

103
Q

What is the most plentiful plasma protein?

A

Albumin

104
Q

What is the primary determinant of plasma oncotic pressure?

A

albumin

105
Q

What is the half life of albumin?

A

3 weeks

106
Q

Albumin can serve as a measurement of

A

protein synthesis

107
Q

Albumin reflect chronic or acute changes?

A

Chronic but not acute changes.

108
Q

ALbumin carries + or - change

A

negative

109
Q

Albumin binds primarily to ____drugs , however it also binds to

A

Acidic: neutral and basic drugs.

110
Q

2 Proteins that binds to basic drugs

A

Alpha 1 acid glycoprotein

Beta globulin

111
Q

Conditions that decreases albumin

A 
Liver disease
Renal disease
old age
Malnutrition
Pregnancy
112
Q

5 Conditions that increase Alpha 1 acid glycoprotein

CROMS

A 
Chronic pain
RA
Old age
MI
Surgical stress
113
Q

Conditions that Decreased alpha 1 acid glycoprotein

A

Neonates

pregnancy

114
Q

Alterations in plasma protein binding can theoritically affect

A

Drugs therapeutic effect.

115
Q

Changes in protein binding can result from 2 things

A

Decreased plasma protein

Competition for binding sites on the protein

116
Q

Decreased plasma protein mediated by those 3 things

A 
Reduced synthetic function (Liver disease , malnutrition)
Increased protein excretion (renal disease)
Altered distribution (3rd trimester of pregnancy)
117
Q

How does pregnancy decrease plasma protein?

A

There is altered distribution

118
Q

How does renal disease decrease plasma protein?

A

Increased protein excretion

119
Q

How does reduced synthetic function decrease plasma protein?

A

Liver disease and malnutrition

120
Q

Steady state between the bound and the unbound fractions will be re-established after

A

5 half lives have elapsed.

121
Q

Relationship of Vd and plasma protein binding

A

Inversely related

122
Q

2 things that can displace drugs from protein binding site.

A

Bilirubin and thyroxine.

123
Q

Kinetic model describes the process that metabolizs a constant amount of drugs per unit time/

A

Zero order kinetic

124
Q

Constant fraction of the drug is metabolized per unit time

A

First order kinetic.

125
Q

For the majority of drugs the rate of metabolism is dependent on what 2 factors

A
  1. Concentration of site of metabolism (influenced by blood flow)
  2. Intrinsic rate of the metabolic process. influenced by genetics, enzyme induction, enzyme inhibition
126
Q

Situation where there is more drug than enzyme

A

Zero order kinetic. , biotransformation process becomes saturated.

127
Q

In zero order kinetic what happens

A

Not enough enzyme is available to metabolize all the drug that is delivered to it. The enzyme will metabolize a constant AMOUNT PER UNIT OF TIME>

128
Q

First order kinetics: the enzyme will

A

metabolized a constant fraction per unit time.

129
Q

Can first order convert to zero order?

A

Yes it is possible for a drug that follows first order kinetics to change to zero order kinetics if the enzymatic pathway becomes saturated.

130
Q

Drug metabolism is divided in 3 phases :

A

Phase I
Phase II
Phase III

131
Q

Phase I of drug metabolims is

A

Modification mediated by Oxidation, reduction , hydrolysis

132
Q

Phase II of drug metabolism is

A

Conjugation

133
Q

Phase III of drug metabolism is

A

Excretion

134
Q

The enzymatic process of altering the chemical structure of a molecule?

A

metabolism or biotransformation.

135
Q

Primary organ of metabolims?

A

Liver

136
Q

The hepatic microsomal enzymes of the p450 system are generally confined to the

A

Smooth Endoplasmic reticulum

137
Q

Another site of primary metabolism other than liver

A

plasma.

138
Q

Key reactions in plasma related to metabolism

A

Hoffman elimination

139
Q

Hoffman elimination are depended on 2 factors

A

pH

temperature.

140
Q

Hydrolysis reaction are catalyzed by

A

Non-specific esterases

Pseudocholinesterase.

141
Q

The primary role of metabolism is to

A

Change a lipid soluble, pharmacologically active compound into a water soluble , pharmacologically inactive byproduct.

142
Q

With metabolims, by creating molecules with greater water solubility _______Ionization and _____Vd

A

Increases Ionization and decreases their vd.

143
Q

Increase ionization and decrease vd faciliate

A

delivery to the kidneys for elimination.

144
Q

Also able to eliminate products

A

GI tract.

145
Q

If the body was unable to change a lipid soluble into a water soluble byproducet, the lipid soluble drug would be

A

continuously reabsorbed by the renal tubules into the pericapillary fluid and returned to the plasma. Drug would remain in the body for a very long time.

146
Q

Sometimes body converts an inactive molecuel into a pharmacologically active molecule called

A

PRODRUG

147
Q

Fospropofol is a

A

Prodrug that is metabolized by ALKALINE PHOSPHATASE to its active metabolite PROPOFOL

148
Q

Fospropofol metablized by

A

Alkaline phosphatase

149
Q

Phase one reactions results in

A

small molecular changes that increase the polarity of a molecule to prepare it for a phase 2 reaction.

150
Q

Most phase I biotransformation are carried by the

A

P450 system.

151
Q

Oxidation work by

A

Adds an oxygen molecule to a compound.

152
Q

Reduction work by

A

Add electron to a compound

153
Q

Hydrolysis work by

A

Add water to a compound to split it apart

154
Q

Phase 2 reactions do what

A

conjugates an endogenous, highly polar, water soluble substrate to the molecule. this results in a soluble, biologically inactive molecule ready for excretions.

155
Q

Common substrate for phase II conjugation reactions:

A 
Glucuronic acid
Glycine
Acetic acid
Sulfuric acid
Methyl group
156
Q

Do all drugs require phase I or Phase II?

A

Some drugs do not require preparation by phase I reactions, and may proceed directly to phase II reactions.

157
Q

What is ENTERO HEPATIC CIRCULATION?

A

Some conjugated compound are excreted in the bile, reactivated in the intestine, and then reabsorbed into the systemic circulation. (BIS)

158
Q

Example of drugs that UNDERGOES enterohepatic circulation?

A

Diazepam.

159
Q

Phase 3 which is elimination involves? present where?

A

ATP dependent carrier proteins that transport drugs across cell membranes. These kidney, liver, GIT

160
Q

3 drugs that under perfusion dependent hepatic elimination ?

A

Propofol
Fentanyl
Lidocaine

161
Q

2 drugs that undergo capacity dependent hepatic elimination ?

A

Diazepam

Rocuronium

162
Q

Hepatic clearance is the product of

A

Liver blood flow - how much is delivered to liver

Hepatic extraction ratio - how much is removed by liver

163
Q

The extraction ration is a measure of how

A

how much drugs is delivered to clearing organ vs how much is removed by that organ

164
Q

Extraction ratio=

A

Arterial concentration - venous concentration/ arterial concentration.

165
Q

Extraction ratio of 1 means that

A

100% of the drug delivered to the clearing organ is removed.

166
Q

Extraction ratio of 0.5 means that

A

50% of the drug delivered to the clearing organ is removed.

167
Q

Flow limited elimination is defined by an ER

A

> 0.7

168
Q

For a drug with HIGH HEPATIC RATIO >0.7 clearance id dependent on

A

LIVER BLOOD FLOW

169
Q

High hepatic ratio defined as

A

ER > 0.7

170
Q

For high hepatic ration drugs, hepatic blood flow

A

Greatly exceed enzymatic activity, so alteration in hepatic enzymes has little effect.

171
Q

For High ER drugs increase liver blood flow leads to_____Clearnce

A

increase

172
Q

ER relationship to Clearance

A

Directly proportional.

173
Q

There are 2 types of clearance as far as ER

A

Flow limited

Capacity limited

174
Q

Drugs with low ER undergo

A

Capacity limited elimination

175
Q

Low hepatic extraction ratio defined as

A

ER < 0.3

176
Q

For low hepatic extraction ratio, clearance depends on

A

ability of the liver to extract drug from the blood.

177
Q

Low ER and changes in hepatic enzyme activity

A

Changes in hepatic enzyme activity or protein binding have a profound impact on clearance of these drugs.

178
Q

Alteration in liver blood flow minimally affect clearance with

A

drugs with LOW ER because only a small amount of drug is removed per unit time.

179
Q

Changes in the liver’s intrinsic ability to remove drug from the blood is influenced by

A

the amount of enzyme present.

180
Q

Enzyme induction effect on clearance

A

Increase clearance.

181
Q

Enzyme inhibition effect on clearance

A

Decrease clearance

182
Q

When administered orally , high ER drugs are subject to what?

A

First pass metabolism. After the drug is absorbed from the GIT, it is delivered to the portal circulation, where a portion of it is metabolized before the drug can reach the biophase. The oral dose must be adjusted to compensate this effect. This explain discrepancies between oral and IV dose regimens.

183
Q

Drugs not affected by liver blood flow or hepatic enzyme activity?

A

Remifentanil

184
Q

Low hepatic ER Drugs

A 
Rocuronium
Diazepam
Lorazepma
Methadone
Thiopental
Theophilline
Phenytoin.
185
Q

High ER drugs : to get questions right not necessarily all the class mentioned

A 
CCBs
BBs
opioids
LAs
Narcan
186
Q

Codeine is biotransformed to its active metabolite

A

Morphine CYP 2D6

187
Q

Which drugs inhibits codeine metabolims?

A

Prozac

188
Q

Quinidine and SSRIs on CYP2D6

A

Inhibit Cyp2D6

189
Q

Poor choices for patients taking Quinidine and SSRIs?

A

Codeine , oxycodone, hydrocodone because they will not be effectively metabolized to morphine and will fail to provide adequate pain relief.

190
Q

What is the most important mechanism of drugs biotransformation in the body?

A

P450 system

191
Q

Other name for P450

A

Mixed function oxidase system

Monooxygenases

192
Q

P450 enzymes are located where

A

Smooth ER of the Hepatocyte.

193
Q

P450 also located in extrahepatic tissue such as

A

lung, kidenys, skin, adrenal gland, GIT

194
Q

What contribute to variations in enzyme efficiency from person to person?

A

Genetic polymorphisms

195
Q

What is the most important cytochrome P450 enzymes?

A

CYP 3A4 Metabolizing 50% drugs that we administer

196
Q

What is the OTHER important cytochrome P450 enzymes?

A

CYP2D6

197
Q

A unique feature of the P450 system is that

A

Exogenous chemicals can influence the expression of these enzymes

198
Q

An enzyme inducer stimulates

A

synthesis of additional enzyme.

199
Q

How does enzyme induction affect clearance and half time?

A

Increases drug clearance

Reduced T1/2

200
Q

An enzyme inhibitor

A

Competes for binding site on an enzyme. Few binding sites available

201
Q

How does enzyme induction affect clearance and half time?

A

Decrease drug clearance

Increase T1/2

202
Q

Examples of Enzymes inducers (RPPCSC)

A 
Rifampin
Phenytoin
Phenobarbital (barbiturates)
Carbamezepine
Smoking tobacco
Consuming alcohol
203
Q

How does enzyme induction affect the dose, plasma level and clearance?

A

Dose increase may be required.
Plasma level decreased
Clearance increase.

204
Q

How does enzyme inhibition affect the dose, plasma level and clearance?

A

Dose decrease may be required
Plasma level increased
Clearance decrease

205
Q

Examples of Enzyme inhibitors (CAGEKOI)

A 
Cimetidine
Amiodarone
Grapefruit Juice
Erythromycin
Ketoconazole
Omeprazole
Isoniazid
206
Q

Inducers of CYP2D6

A

Disulfiram

207
Q

Inhibitors of CYP2D6

A

SSRIs
Isoniazid
Quinidine

208
Q

CYP1A2 substrate

A

Theophilline *small therapeutic index

209
Q

CYP2D6 substrate

A

Codeine
Oxycodone
Hydrocodone

210
Q

CYP1A2 inducers

A

Tobacco
Cannabis
Ethanol

211
Q

CYP1A2 inhibitors

A

Erythromycin

Ciprofloxacin

212
Q

Organic anion transporters are present in the

A

Proximal Convoluted tubule, they actively secrete anions into the urine.

213
Q

Key function of kidney is the

A

Elimination of metabolic waste into the urine

214
Q

Drugs fate is determined by its

A

Polarity and the pH of the glomerular fluid

215
Q

Hydrophillic drugs will be excreted

A

unchanged

216
Q

Lipophillic drugs and excretion

A

Must undergo biotransformation reactions to increase their water solubility before they can be excreted by the kidneys.

217
Q

Lipophillic drugs that HAVE NOT undergone biotransformation , will be

A

reabsorbed into the peritubular fluid by diffusion.

218
Q

There are 2 processes that deliver drug to the urine

A

Glomerular filtration

Organic ion transporters.

219
Q

Glomerular filtration : drugs that are not bound to plasma proteins

A

Will be freely filtered by the glomerulus

220
Q

Glomerular filtration : drugs that are HIGHLY bound to plasma proteins

A

resistant to glomerular filtration, only the free fraction will be filtered.

221
Q

Organic anion and cation transporters; Transport proteins located in the proximal renal tubules actively

A

Secrete organic acids, and bases into the urine.

222
Q

Organic anion transporters (OAT)

A

Furosemide
Thiazide diuretics
PCN

223
Q

Organic cation transporters (OCT)

A

Morphine
Meperidine
Dopamine

224
Q

Urine ph Influence what

A

Whether drugs are excreted in urine or reabsorbed into the peritubular capillaries,.

225
Q

Like dissolves

A

like

226
Q

AAA

A

Acidic drugs are better Absrobed in an ACIDIC MEDIUM

227
Q

BBB

A

Basic drugs are Better absorbed in a BASIC medium

228
Q

2 things that can acidify the urine? how does this help?

A

Ammonium chloride
Cranberry juice
Helps eliminate basic drugs.

229
Q

2 things that can alkalize the urine? how does this help?

A

Sodium bicarbonate
Acetazolamide
helps eliminated acidic drugs

230
Q

Enzymatic drug metabolism in the plasma tends to occur via one of three pathways?

A

Pseudocholinesterase
Nonspecific esterase
Alkaline Phosphatase

231
Q

Drugs metabolize via pseudocholinesterase:

A

Succinylcholine, COCAINE (+hepatic)

Ester LAs

232
Q

Drugs metabolize via Nonspecific esterase

A 
REEAh
Remifentanil
Esmolol
Etomidate
Atracurium (+hoffman)
233
Q

Drugs metabolize by alkaline phosphatase

A

Fospropofol

234
Q

Hoffman elimination takes place where?

A

Plasma.

235
Q

Drugs by both hoffman + nonspecific esterases

A

Atracurium

236
Q

Drugs that undergo hoffman elimination benzoisoquinoliium

A

Cisatracurium

237
Q

Causes the opposite effect to that of a full agonists and example?

A

Inverse agonist

Propranolol

238
Q

Occupies the receptor binding site and prevents agonist from binding to it , does not tell the cell to do anything? Example?

A

ANTAGONIST

Cisatracurium

239
Q

Is only capable of partially turning on a cellular response

A

PARTIAL AGONIST

Nalbuphine

240
Q

Can maximally turn on a specific cellular response?

A

AGONIST

Propofol

241
Q

Pharmacological effect of 2 drugs given at the same time will be greater than the sum of their individual effects
1+1 = 3

A

Synergism

242
Q

Pharmacological effect of 2 drugs given at the same time are added to each other 1+1 =2

A

Addition

243
Q

Simultaenous administration of one drug cancels out the effect of a second drug 1+1 =

A

0

244
Q

Major flaw of the context sensitive half time

A

It only illustrates the time it takes for the concentration to decline by 50% in the central compartment. Meaning it does not necessarily predict the time to wake-up after an infusion is stopped.

245
Q

Enantiomeric drugs supplied as racemic mixtures:

A

Ketamie
Ephedrine
Desflurane

246
Q

Biotransformation of morphine to

A

Morphine-6-Glucuronide

247
Q

Biotransformation of morphine to Morphine-6-Glucuronide is an example of

A

Conjugation

248
Q

3 drugs that exhibit ZERO order (LINEAR) kinetics

A 
WE PATH
Warfarin
Ethanol
Phenytoin
Aspirin
Theophylline
Heparin
249
Q

Drug must likely to cause theophilline toxicity?

A

Erythromycin

SEE/BOARD STUDY (20 decks)

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