Deck 4: Pharmacology Basics

Question 1

Match the following:

-Amide

A) Contains a nitrogen atom
B) Identifies chemical nature of local anesthetic drug
C) Uncharged molecule
D) Effect of local anesthetic drug on nerve membrane
E) Restricts vascular flow
F) pKa
G) Removal of drug by kidneys
H) 50% of drug is removed from circulation
I) Positively charged ion
J) Body's management of a drug

Answer 1

Contains a nitrogen atom

Question 2

Match the following:

-Biotransformation

A) Contains a nitrogen atom
B) Identifies chemical nature of local anesthetic drug
C) Uncharged molecule
D) Effect of local anesthetic drug on nerve membrane
E) Restricts vascular flow
F) pKa
G) Removal of drug by kidneys
H) 50% of drug is removed from circulation
I) Positively charged ion
J) Body's management of a drug

Answer 2

Body's management of a drug

Question 3

Match the following:

-Cation

A) Contains a nitrogen atom
B) Identifies chemical nature of local anesthetic drug
C) Uncharged molecule
D) Effect of local anesthetic drug on nerve membrane
E) Restricts vascular flow
F) pKa
G) Removal of drug by kidneys
H) 50% of drug is removed from circulation
I) Positively charged ion
J) Body's management of a drug

Answer 3

Positively charged ion

Question 4

Match the following:

-Dissociation constant

A) Contains a nitrogen atom
B) Identifies chemical nature of local anesthetic drug
C) Uncharged molecule
D) Effect of local anesthetic drug on nerve membrane
E) Restricts vascular flow
F) pKa
G) Removal of drug by kidneys
H) 50% of drug is removed from circulation
I) Positively charged ion
J) Body's management of a drug

Question 5

Match the following:

-Elimination

A) Contains a nitrogen atom
B) Identifies chemical nature of local anesthetic drug
C) Uncharged molecule
D) Effect of local anesthetic drug on nerve membrane
E) Restricts vascular flow
F) pKa
G) Removal of drug by kidneys
H) 50% of drug is removed from circulation
I) Positively charged ion
J) Body's management of a drug

Question 6

Match the following:

-Elimination half-life

A) Contains a nitrogen atom
B) Identifies chemical nature of local anesthetic drug
C) Uncharged molecule
D) Effect of local anesthetic drug on nerve membrane
E) Restricts vascular flow
F) pKa
G) Removal of drug by kidneys
H) 50% of drug is removed from circulation
I) Positively charged ion
J) Body's management of a drug

Question 7

Match the following:

-Intermediate chain

A) Contains a nitrogen atom
B) Identifies chemical nature of local anesthetic drug
C) Uncharged molecule
D) Effect of local anesthetic drug on nerve membrane
E) Restricts vascular flow
F) pKa
G) Removal of drug by kidneys
H) 50% of drug is removed from circulation
I) Positively charged ion
J) Body's management of a drug

Question 8

Match the following:

-Neutral base

A) Contains a nitrogen atom
B) Identifies chemical nature of local anesthetic drug
C) Uncharged molecule
D) Effect of local anesthetic drug on nerve membrane
E) Restricts vascular flow
F) pKa
G) Removal of drug by kidneys
H) 50% of drug is removed from circulation
I) Positively charged ion
J) Body's management of a drug

Question 9

Match the following:

-Specific receptor theory

A) Contains a nitrogen atom
B) Identifies chemical nature of local anesthetic drug
C) Uncharged molecule
D) Effect of local anesthetic drug on nerve membrane
E) Restricts vascular flow
F) pKa
G) Removal of drug by kidneys
H) 50% of drug is removed from circulation
I) Positively charged ion
J) Body's management of a drug

Question 10

Match the following:

-Vasoconstrictor

A) Contains a nitrogen atom
B) Identifies chemical nature of local anesthetic drug
C) Uncharged molecule
D) Effect of local anesthetic drug on nerve membrane
E) Restricts vascular flow
F) pKa
G) Removal of drug by kidneys
H) 50% of drug is removed from circulation
I) Positively charged ion
J) Body's management of a drug

Question 11

Which of the following is not a desirable characteristic of local anesthetic drugs?

A) Biotransformable and easily eliminated
B) Nonirritable
C) Nontoxic to neural structures
D) Easily distributed

Question 12

Which of the following local anesthesia drugs is available without a vasoconstrictor?

A) Lidocaine
B) Articaine
C) Bupivacaine
D) Procaine

Question 13

Which of the following is not a trade name for lidocaine?

A) Xylocaine
B) Octocaine
C) Lignocaine
D) Carbocaine

Question 14

Trade names for prilocaine include:

A) Zorcaine and Citanest
B) Citanest and Citanest forte
C) Isocaine and Carbocaine
D) Octocaine and Marcaine

Question 15

Which of the following local anesthetic drugs is available in a 0.5% concentration?

A) Prilocaine
B) Mepivacaine
C) Articaine
D) Bupivacaine

Question 16

Which statement is false regarding the intermediate chain of local anesthetic drugs?

A) Affects the method of biotransformation
B) Separates an aromatic end and a secondary or tertiary amine
C) Contains a nitrogen atom in amides
D) Contains both lipophilic and hydrophilic properties

Question 17

Which form(s) of a local anesthetic drug is (are) responsible for the actions of the drug on nerve membranes?

A) Cation and neutral base
B) Ester and amide
C) Positive cation
D) Neutral base

Question 18

Which statement is false regarding the vasoactivity of local anesthetic drugs?

A) All local anesthestic drugs are peripheral vasodilators.
B) It is not a desired characteristic
C) It affects both duration and efficacy
D) Their vasoactivity decreases toxicity

Question 19

Approximately what percentage of the action of local anesthetic drugs is due to cation binding at specific protein receptor sites?

A) 100%
B) 90%
C) 10%
D) 4%

Question 20

During normal nerve function, which ion is displaced when a membrane is stimulated?

A) Sodium
B) Calcium
C) Potassium
D) Neutral salt

Question 21

Which one of the following local anesthetic ions binds to specific receptor sites?

A) NA⁺
B) NA^-
C) CA⁺²
D) K⁺

Question 22

Which portion of a local anesthetic molecule passes through nerve membranes?

A) Base
B) Cation
C) Hydrophilic base
D) Base and cation

Question 23

Which portion of local anesthetic molecules binds to receptor sites within nerve membranes, preventing depolarization?

A) Lipophilic base
B) Neutral base
C) Sodium cation
D) Cation

Question 24

What factor influences the shift of the neutral base (RN) molecule to the cation (RNH+) within the axoplasm?

A) Lower pH of axoplasm than extracellular fluid
B) Fewer H+ ions available in axoplasm
C) Sufficient H+ ions available in axoplasm at pH of 7.4
D) Higher number of base molecules within the axoplasm due to inflammation

Question 25

Which of the following best explains the membrane expansion theory?

A) Membrane ion channels narrow due to diffusion of local anesthetic molecules into lipophilic regions of the membranes
B) Membrane ion channels narrow due to diffusion of local anesthetic molecules into hydrophilic regions of the membranes
C) Diffusion of local anesthetic molecules bind in the nerve channels causing a narrowing of lipophilic ion channels
D) Dissociation of local anesthesia molecules narrows membrane channels blocking influx of sodium and calcium ions

Question 26

Approximately what percentage of the action of local anesthetic drugs is due to the membrane expansion theory?

A) 90%
B) 60%
C) 10%
D) 5%

Question 27

What factor decreases the effectiveness of local anesthesia when tissues are inflamed?

A) An increase in the pH of surrounding tissues
B) A decrease in the pH of surrounding tissues
C) An increases in the number of base molecules
D) A decrease in the number of H+ ions available to form base molecules

Question 28

Why do manufacturers alter the pKa of local anesthetic drugs?

A) Increase the duration of anesthesia
B) Decease the duration of anesthesia
C) Provide useful onset time of anesthesia
D) Provide more profound anesthesia

Question 29

What is the clinical effect of a local anesthetic drug solution with a higher pKa?

A) Increased base molecule concentration and thereby slower onset of anesthesia
B) Increased cation molecule concentration and thereby faster onset of anesthesia
C) Increased base molecule concentration and thereby faster onset of anesthesia
D) Decreased base molecule concentration thereby slower onset of anesthesia

Question 30

Which statement is false regarding the absorption and distribution of local anesthetic drugs?

A) Once absorbed into the systemic circulation the drugs are distributed throughout the body.
B) The lungs, brain, heart, and kidneys will receive more drug because they are highly perfused with blood.
C) Injection into highly vascular regions will result in faster absorption and distribution.
D) Bone and epithelium will receive more drug.

Question 31

Which body system (by mass) receives the highest concentration of anesthetic drugs?

A) Liver
B) Skin
C) Muscle
D) Bone

Question 32

Biotransformation of current local anesthetic drugs occurs primarily through:

A) Liver or blood
B) Liver and intestines
C) Kidney and blood
D) Liver and kidney

Question 33

Most amide local anesthetics are biotransformed in the:

A) Blood by P450 isoenzymes
B) Liver by P450 isoenzyme
C) Blood by pseudocholinesterase
D) Kidneys and liver by P450 isoenzymes and pseudocholinerase

Question 34

Prilocaine is biotransformed by the:

A) Liver
B) Liver and blood
C) Liver, kidneys, and lungs
D) Liver, lungs, and large intestines

Question 35

Ester-type local anesthestic drugs are biotransformed in the:

A) Liver by hepatic enzymes
B) Kidney by cholinesterase
C) Blood by the isoenzyme system
D) Blood by pseudocholinesterase

Question 36

CNS toxicity occurs due to:

A) Normal function of nerve cells
B) Nerve damage during injection
C) Compromised vascular supply
D) Inadequate amount of local anesthesia

Question 37

Which of the following signs and symptoms are not signs of CNS overdose toxicity?

A) Apprehension, excitedness, talkativeness
B) Bilateral numbness of tongue, perioral numbness
C) Muscle twitching, tremors
D) Hypotension, lower pulse, slower breathing

Question 38

Which of the following signs and symptoms are not signs of CVS overdose toxicity?

A) Depression of myocardial conduction rate
B) Vasoconstriction of peripheral vasculature
C) Hypotension
D) Depression of force of myocardial contraction

Question 39

Which local anesthetic drug can be harmful at higher blood levels however useful in treating cardiac arrhythmias?

A) Bupivacaine and procaine
B) Procaine and prilocaine
C) Lidocaine and procaine
D) Lidocaine and prilocaine

Question 40

Elimination half-life refers to the time it takes for half of a drug to be:

A) Metabolized
B) Out of the lungs
C) Out of the circulation
D) Out of half of the circulation

Question 41

What is the half-life of lidocaine?

A) 6.25 hours
B) 1.6 hours
C) 50%
D) 3.5 hours

Question 42

If the fourth half-life of lidocaine is 12.5%, what is the fifth half-life?

A) 50%
B) 1.8%
C) 0.32%
D) 6.25%

Question 43

Which local anesthetic drug has the shortest half-life?

A) Articaine
B) Prilocaine
C) Mepivacaine
D) Bupivacaine

Question 44

Which drug could be a good choice for a nursing mother who plans to nurse her child soon after an appointment?

A) Bupivacaine
B) Mepivaciane
C) Prilocaine
D) Articaine

Question 45

What is the half-life of bupivacaine?

A) 0.75 hours
B) 3.5 hours
C) 1.6 hours
D) 1.9 hours

Question 46

What is the primary benefit of local anesthesia?

Question 47

Discuss the ideal properties of local anesthetic drugs used in dentistry.

Question 48

How does the vascularity of an injection site affect the absorption and distribution of a local anesthetic drug?

Question 49

How does tissue inflammation affect local anesthetic drug efficacy?

Question 50

Discuss factors that can precipitate toxic overdose from local anesthetic drugs.