Deck 7: Antiinfective Agents

Question 1

The possibility of superinfection can be minimized by use of the _____ specific antiinfective agent,the _____ effective course of therapy,and adequate doses.

A)least;shortest
B)least;longest
C)most;shortest
D)most;longest

Answer 1

most;shortest

Question 2

Which of the following statements is true concerning the pharmacokinetics of penicillin?

A)Penicillin may be administered orally,parenterally,or topically.
B)Penicillin G is better absorbed orally than penicillin V;thus,penicillin G is used for administration of oral penicillin.
C)Penicillin V and amoxicillin can be taken without regard to meals.
D)Penicillin does not cross the placenta and will not appear in breast milk.

Answer 2

Penicillin V and amoxicillin can be taken without regard to meals.

Question 3

Which of the following periodontal diseases is usually not treated with antimicrobials?

A)Periodontal abscess
B)Localized juvenile periodontitis
C)Adult periodontitis
D)Rapidly advancing periodontitis

Answer 3

Adult periodontitis

Question 4

Which of the following antibiotics are not associated with any teratogenicity and are often used in pregnant women?

A)Penicillin
B)Tetracyclines
C)Erythromycin
D)Metronidazole
E)Both A and C

Question 5

Which of the following choices is the dental hygienist's biggest dental problem in the adult patient?

A)Caries
B)Periodontal disease
C)Localized dental infection
D)Systemic dental infection

Question 6

Superinfection describes a(n)

A)nonsystemic,superficial infection.
B)exaggerated infection caused by treating a resistant pathogen.
C)opportunistic infection that arises as a consequence of treatment.
D)infection by multiple pathogens.

Question 7

The misuse of antibiotics has contributed to antibiotic resistance.The solution to reducing the incidence of antibiotic-resistant bacteria is to write more prescriptions for antibiotics.

A)Both statements are true.
B)Both statements are false.
C)The first statement is true,the second is false.
D)The first statement is false,the second is true.

Question 8

Which of the following statements is true concerning antibiotic resistance?

A)Natural resistance occurs when an organism that was previously sensitive to an antimicrobial agent develops resistance.
B)An increase in the use of an antibiotic in a given population decreases the proportion of resistant organisms in that population.
C)Bacterial resistance can occur by the transfer of deoxyribonucleic acid (DNA)genetic material from one organism to another.
D)The transfer of genetic material from one organism to another may only occur among organism of the same species.

Question 9

Which of the following agents is the drug of choice for an early dental infection unless the patient is allergic to it?

A)Erythromycin
B)Clindamycin
C)Penicillin
D)Metronidazole

Question 10

_____ has the highest incidence of gastrointestinal complaints of any of the antibiotics.

A)Penicillin
B)Erythromycin
C)Clindamycin
D)Cephalosporin

Question 11

Penicillinase inactivates the penicillin moiety by

A)sublimation.
B)desiccation.
C)cleaving the b-lactam ring.
D)cleaving the S-containing thiazolidine ring.

Question 12

Superinfection is more often caused by _____-spectrum antibiotics and increases when taken for a _____ time period.

A)narrow;shorter
B)narrow;longer
C)broad;shorter
D)broad;longer

Question 13

Antiinfective agents can potentiate the effect of oral anticoagulants by interfering with the production of vitamin

A)A.
B)D.
C)E.
D)K.

Question 14

If an infection is just beginning,the organisms most likely to be present are

A)gram-positive cocci.
B)gram-negative cocci.
C)gram-positive anaerobes.
D)gram-negative anaerobes.

Question 15

An _____ agent is a substance that destroys or suppresses the growth or multiplication of bacteria.

A)antiinfective
B)antibacterial
C)antibiotic
D)antimicrobial

Question 16

The disease-producing power of the microorganism is called

A)resistance.
B)superinfection.
C)infection.
D)virulence.

Question 17

Which of the following antiinfective agents is bacteriostatic,but may be bactericidal at higher dose levels?

A)Cephalosporins
B)Metronidazole
C)Penicillins
D)Erythromycin
E)Vancomycin

Question 18

Which of the following antibiotics is associated with pseudomembranous colitis?

A)Penicillin
B)Erythromycin
C)Clindamycin
D)Metronidazole

Question 19

Which of the following statements is true concerning infection and host resistance?

A)Host resistance should be considered as having both local and systemic components.
B)If a patient has diabetes mellitus it can reduce the resistance to an infection.
C)Drugs such as steroids are capable of enhancing a patient's immune response.
D)Both A and B
E)Both B and C

Question 20

Dental caries is caused by an infection with

A)Porphyromonas gingivalis.
B)Eikenella corrodens.
C)Streptococcus mutans.
D)Fusobacterium.

Question 21

Which of the following statements is true of the tetracyclines?

A)They are bactericidal.
B)Tetracyclines interfere with the synthesis of bacterial protein by binding at the 50S subunit of bacterial ribosomes.
C)In the study of sensitivity or organisms isolated from dental infections,one-fifth to two-fifths of Staphylococcus aureus (S.aureus)were found to be resistant to tetracycline.
D)Tetracyclines are not prone to enterohepatic circulation.

Question 22

Which of the following antibiotics is available mixed with clavulanic acid?

A)Ampicillin
B)Amoxicillin
C)Carbenicillin
D)Azithromycin

Question 23

Clavulanic acid is

A)a bacteriostatic antibiotic.
B)a bactericidal antibiotic.
C)a b-lactamase inhibitor.
D)Both A and C
E)Both B and C

Question 24

The usual adult dose of penicillin V for treatment of an infection is

A)250 mg twice a day (bid).
B)250 mg four times a day (qid).
C)250 to 500 mg twice a day (bid).
D)250 to 500 mg four times a day (qid).

Question 25

Which of the following agents is the drug of first choice against infections caused by aerobic microorganisms in penicillin-allergic patients?

A)Metronidazole
B)Erythromycin
C)Doxycycline
D)Clindamycin

Question 26

Which of the following salts of penicillin G produces the most rapid and highest blood level?

A)Potassium salt given intravenously
B)Potassium salt given intramuscularly
C)Benzathine salt given intramuscularly
D)Procaine salt intramuscularly

Question 27

Azithromycin and clarithromycin

A)cause lysis of the bacterial cell wall.
B)are not effective against anaerobes.
C)have a higher incidence of adverse reactions than erythromycin.
D)may be used as alternative antibiotics for the prophylaxis of endocarditis and prosthetic joint infections.

Question 28

Which drug should be used before oral prophylaxis prior to dental treatment for a patient who has rheumatic heart disease with no known drug allergies?

A)Amoxicillin
B)Tetracycline
C)Clindamycin
D)Erythromycin
E)None of the above

Question 29

Which of the following statements is true regarding penicillinase-resistant penicillins?

A)Penicillinase-resistant penicillins should be reserved for use against only penicillinase-producing staphylococci.
B)Penicillinase-resistant penicillins are more effective against penicillin G-sensitive organisms when compared with penicillin G.
C)Penicillinase-resistant penicillins produce fewer side effects when compared with penicillin G.
D)Patients allergic to penicillin are not also allergic to the penicillinase-resistant penicillins.

Question 30

Which of the following statements is true regarding penicillin allergy?

A)Allergic reactions with oral penicillin are more common than with parenteral penicillin.
B)Anaphylactic reactions are more frequent in patients pretreated with b-blockers and subsequently given oral penicillin.
C)The treatment of anaphylaxis caused by penicillin is the immediate administration of corticosteroids.
D)Estimates indicate that 10,000 to 30,000 deaths occur annually in the United States because of an allergic reaction to penicillin.

Question 31

Clavulanic acid is used to fight infections with which of the following resistance mechanisms?

A)Decreased permeability to the agent
B)Production of drug-inactivating enzymes
C)Alteration in the site of action
D)Any of the above

Question 32

_____ is the drug of choice for prophylaxis to prevent bacterial endocarditis before a dental procedure.

A)Penicillin G
B)Penicillin V
C)Ampicillin
D)Amoxicillin

Question 33

Large doses of cephalosporins often produce a Coombs reaction,which means

A)high blood pressure is exacerbated.
B)the immune mechanism is attacking the patient's own red blood cells.
C)degeneration of neural glial cells occurs.
D)nephritis of the kidneys occurs.

Question 34

Some studies indicate that _____% of patients receiving penicillin will have an anaphylactic reaction.

A)0.05 to 0.10
B)0.5 to 1
C)5 to 10
D)20 to 25

Question 35

A cephalosporin would be most closely related to which of the following agents?

A)Penicillin VK
B)Clarithromycin
C)Ciprofloxacin
D)Doxycycline
E)Clindamycin

Question 36

Which of the following conditions is the most common adverse reaction from the administration of erythromycin?

A)Anaphylaxis
B)Skin rash
C)Gastrointestinal effects
D)Miosis

Question 37

Which of the following statements is true of the cephalosporins?

A)They are active against gram-positive but not gram-negative organisms.
B)Those available for oral use are susceptible to penicillinase.
C)They are bacteriostatic.
D)Their mechanism of action is inhibition of cell wall synthesis.

Question 38

Which of the following agents allows the use of amoxicillin to treat penicillinase-producing organisms?

A)Clavulanic acid
B)Divalent cations
C)Corticosteroids
D)Disulfiram

Question 39

Which of the following statements is true concerning the pharmacokinetics of erythromycin?

A)Erythromycin is broken down in gastric fluid and absorbed through the stomach wall.
B)Erythromycin is not available in a topical preparation because of allergenicity.
C)Erythromycin is available in oral but not injectable forms.
D)Erythromycin should be administered 2 hours before or 2 hours after meals.

Question 40

Which of these agents do not inhibit bacterial cell-wall synthesis?

A)Vancomycin
B)Erythromycin
C)Penicillin G
D)Cefazolin

Question 41

Aminoglycosides

A)are bacteriostatic.
B)are used primarily to treat aerobic gram-negative infections when other agents are ineffective.
C)are indicated for stage 1 infections.
D)inhibit cell wall synthesis.

Question 42

Which of the following antimicrobial agents is associated with ototoxicity?

A)Vancomycin
B)Aminoglycosides
C)Nitrofurantoin
D)Quinolones

Question 43

_____ is associated with a severe drug interaction with alcohol.

A)Erythromycin
B)Tetracycline
C)Metronidazole
D)Aminoglycosides (e.g. ,streptomycin)

Question 44

The most common adverse reaction to the sulfonamides is

A)liver damage.
B)suppressed renal function.
C)an allergic skin reaction.
D)blood dyscrasias.

Question 45

Oral-cavity infections are generally understood to advance through three stages.The three stages are (1)mixed aerobic and anaerobic infection, (2)aerobic infection,and (3)anaerobic infection.In what order do these stages occur?

A)1,2,3
B)1,3,2
C)2,1,3
D)3,1,2
E)3,2,1

Question 46

Which of the following agents is most closely associated with the development of pseudomembranous colitis as a toxicity that limits its general use?

A)Erythromycin
B)Clindamycin
C)Penicillin VK
D)Metronidazole

Question 47

Which of the following antibiotics would be the best choice for treatment of an acute abscess or cellulitis in a patient who is not allergic to penicillin?

A)Metronidazole
B)Erythromycin
C)Amoxicillin
D)Clindamycin

Question 48

When a patient with a stage 1 infection is allergic to penicillin V,the best alternative would be

A)penicillin G or ampicillin.
B)erythromycin ethylsuccinate or clindamycin.
C)tetracycline or metronidazole.
D)vancomycin.

Question 49

Which of the following antibiotics is associated with photosensitivity?

A)Erythromycin
B)Tetracycline
C)Metronidazole
D)Aminoglycosides (e.g. ,streptomycin)

Question 50

Which of the following agents is bacteriostatic in action?

A)Amoxicillin
B)Streptomycin
C)Vancomycin
D)Trimethoprim

Question 51

Administration of metronidazole for dental infections during pregnancy is

A)contraindicated.
B)permitted only during the second trimester.
C)permitted during the last half of pregnancy.
D)permitted without restriction.

Question 52

Which of the following statements is true regarding nitrofurantoin?

A)Nitrofurantoin has a narrow spectrum of action against anaerobic bacteria.
B)Nitrofurantoin is bactericidal.
C)Nitrofurantoin is associated with red man syndrome.
D)Nitrofurantoin can cause a brownish discoloration of urine.

Question 53

An erythematous rash on the face and upper body known as red man syndrome is associated with use of which of the following antimicrobial agents?

A)Augmentin
B)Metronidazole
C)Vancomycin
D)Chloramphenicol

Question 54

Which of the following antibiotics would be the best choice to attack the anaerobes in a stage 2 infection?

A)Clindamycin or metronidazole
B)Ampicillin or amoxicillin
C)Amoxicillin or augmentin
D)Ciprofloxacin

Question 55

Which of the following statements is true concerning clindamycin?

A)Clindamycin is distributed throughout most body tissues,including bone.
B)Cross-resistance between clindamycin and erythromycin is often noted.
C)The indications for treatment with clindamycin are limited to a number of infections caused by aerobic organisms.
D)Both A and B are true.
E)Both B and C are true.

Question 56

Which of the following is the most common adverse reaction to administration of metronidazole?

A)Central nervous system effects
B)Gastrointestinal effects
C)Renal toxicity
D)Oral effects

Question 57

Which of the following statements is true of vancomycin?

A)Vancomycin is related to the cephalosporins.
B)Vancomycin is usually administered only intravenously for a systemic effect.
C)Vancomycin is bacteriostatic.
D)Vancomycin has a broad spectrum of action against a wide variety of gram-positive and gram-negative organisms.

Question 58

Tetracyclines should not be used in children younger than _____ years of age.

A)6
B)9
C)12
D)15

Question 59

_____ can cause black pigmentation of mandibular and maxillary alveolar bone and the hard palate.

A)Penicillin V
B)Erythromycin
C)Minocycline
D)Clindamycin

Question 60

The sulfonamides competitively inhibit the bacterial enzyme that incorporates para-aminobenzoic acid (PABA)into an immediate precursor of

A)biotin.
B)thiamine.
C)folic acid.
D)riboflavin.

Question 61

Infective endocarditis prophylaxis with an antiinfective is indicated for patients who have had

A)coronary artery bypass surgery.
B)a prosthetic heart valve.
C)functional murmur.
D)a cardiac pacemaker.

Question 62

Rupture of the Achilles tendon is associated with the use of

A)tetracyclines.
B)quinolones.
C)rifampin.
D)mupirocin.

Question 63

Which antibiotic is useful in the treatment of many anaerobic periodontal infections?

A)Metronidazole
B)Penicillin VK
C)Erythromycin
D)Azithromycin

Question 64

The American Dental Association (ADA)and the American Academy of Orthopedic Surgeons (AAOS)recommend for dentists to prescribe antibiotic prophylaxis for patients with joint replacements.The American Dental Association Council on Scientific Affairs demonstrated the benefits of antibiotic prophylaxis outweigh potential harm.

A)Both statements are true.
B)Both statements are false.
C)The first statement is true,the second statement is false.
D)The first statement is false,the second statement is true.

Question 65

If a patient requires premedication with antibiotics before a dental procedure and he or she is allergic to penicillins or ampicillin but can take oral medication,the drug of choice is

A)tetracycline.
B)metronidazole.
C)cephalexin.
D)amoxicillin.

Question 66

Which type of penicillin is most likely to be administered to a patient in the dental office?

A)Penicillin G
B)Penicillin V
C)Penicillinase-resistant penicillin
D)Ampicillin
E)Ticarcillin

Question 67

An allergic reaction to penicillin will most likely appear as

A)anaphylaxis.
B)a rash.
C)delayed serum sickness.
D)hemolytic anemia.
E)interstitial nephritis.

Question 68

_____ are the first orally active agents against certain Pseudomonas species.

A)Aminoglycosides
B)Sulfonamides
C)Quinolones
D)Tetracyclines

Question 69

Antibiotic prophylaxis to prevent endocarditis is considered reasonable for which of the following dental procedures?

A)Oral radiographs
B)Routine anesthetic injections through uninfected tissues
C)Routine prophylaxis
D)Shedding of deciduous teeth

Question 70

Infective endocarditis is more likely to occur from bacteria entering the bloodstream as a result of daily activities than from a dental procedure.There is no evidence that antibiotic prophylaxis prior to a dental procedure will prevent infective endocarditis in those at risk for developing it.

A)Both statements are true.
B)Both statements are false.
C)The first statement is true,the second statement is false.
D)The first statement is false,the second statement is true.

Question 71

Unlike other antiinfective agents,an additive action may result when _____ is combined with other antimicrobial agents.

A)vancomycin
B)chloramphenicol
C)nitrofurantoin
D)ciprofloxacin

Question 72

Which agent inhibits DNA gyrase?

A)Penicillin G
B)Erythromycin
C)Metronidazole
D)Ciprofloxacin

Question 73

If a person with active TB seeks oral health care

A)use standard precautions and treat him or her just as everyone else is treated.
B)schedule him or her as the last patient of the day.
C)contact that person's physician and delay health care until the disease is no longer in the active state.
D)refer the patient to a hospital with a dental suite for treatment.

Question 74

Penicillin kills bacteria by attacking the

A)50S subunit of the ribosome.
B)30S subunit of the ribosome.
C)cell wall.
D)a subunit of DNA gyrase.

Question 75

Which of the following combinations of three drugs are administered concurrently in active cases of pulmonary tuberculosis (TB)?

A)Pyrazinamide (PZA),rifapentine,and Rifater
B)Isoniazid (INH),rifampin,and pyrazinamide
C)Ethambutol,isoniazid (INH),and Rifater
D)Rifampin,PZA,and streptomycin

Question 76

The standard antibiotic drug regimen prior to dental procedures requiring immunoprophylaxis in a patient with no allergies to penicillin or amoxicillin is _____ g of amoxicillin _____ hour(s)before the procedure.

A)1;1
B)1;2
C)2;1
D)2;2

Question 77

The drug whose future use may include organisms found in periodontal disease is

A)ofloxacin.
B)sulfamethoxazole.
C)macrodantin.
D)streptomycin.

Question 78

Quinolones

A)must be administered parenterally and cannot be taken orally.
B)have no use in dentistry.
C)are bactericidal against most gram-negative organisms and many gram-positive organisms.
D)have cross-resistance with many other antimicrobial agents.

Question 79

Which is a penicillinase-resistant penicillin?

A)Ampicillin
B)Amoxicillin
C)Cloxacillin
D)Ticarcillin
E)Piperacillin

Question 80

Both the American Dental Association (ADA)and the American Academy of Orthopedic Surgeons (AAOS)recommend that which type of patients with joint replacements should receive antibiotic prophylaxis before dental procedures that can lead to bacteremia?

A)All patients for the rest of their lives.
B)All patients for 2 years.
C)Patients with weakened immune systems.
D)No patients.