ANTIBIOTICS

Question 1

Penicillins moa

Answer 1

• Inhibit bacterial cell wall synthesis by blocking the transpeptidation step1

Question 2

Cephalosporins moa

Answer 2

• Structure resembles the penicillins, possessing a β-lactam ring
• Block bacterial cell wall synthesis through inhibition of penicillin-binding proteins that
catalyze transpeptidation

Question 3

Penicillins

Cephalosporins

Tetracyclines

Answer 3

A beta-hemolytic streptococci,
Neisseria species, Treponema pallidum, and Erysipelothrix rhusiopathae
staphylococci and nonenterococcal
streptococci4
Effective against both gram-positive and negative organisms, mycoplasma infections,
Chlamydia and Rickettsia infections

Question 4

Tetracyclines moa

Answer 4

Inhibit protein synthesis by binding to the 30S ribosomal subunit

Question 5

tetracycline, unlike minocycline and doxycycline

Answer 5

impaired by the ingestion

of dairy products, calcium, and iron or zinc salts

Question 6

only tetracycline for use in patients with renal

failure

Answer 6

Doxycycline, excreted by the GI tract

Question 7

most phototoxic of all the tetracyclines

Answer 7

Demeclocycline and doxycycline

Question 8

Tetracyclines are contraindicated

Answer 8

less than 9 years
of age → risk of brown discoloration of the teeth and delayed
bone growtha brown discoloration along the gingival third

Question 9

allergic to penicillins may also exhibit similar

allergic reactions to cephalosporins

Answer 9

10% of patients

Question 10

Tetracyclines ADR

Answer 10

Pneumonitis, drug-induced lupus and serum

sickness-like reactions from tetracyclines have been reported

Question 11

most common

cause of fixed drug eruption

Answer 11

Tetracycline:

Question 12

minocycline stains the permanent teeth in

adults,

Answer 12

with a gray-green discoloration of the midportion of the tooth

Question 13

increased incidence of

serum sickness in children

Answer 13

Cefaclor

Question 14

Inhibit the 50S ribosomal subunit during protein synthesis

Answer 14

MACROLIDE

Question 15

gram-negative soft-tissue infections

Answer 15

Azithromycin and clarithromycin

Question 16

cne, pyodermas, erythrasma,

and pitted keratolysis

Answer 16

Erythromycin

Question 17

Cholestatic hepatitis is associated
with the ? form of
erythromycin12

Answer 17

estolate

Question 18

inhibiting the cytochrome P-450

Answer 18

• Erythromycin
increasing levels of carbamezapine, warfarin, theophylline, phenytoin, digoxin, and
terfenadine

Question 19

Fluoroquinolones

Answer 19

• Inhibit DNA gyrase

Question 20

Mycobacterium species, gram-negative infections, particularly
Enterobacteriaceae organisms and multiresistant bacteria

Answer 20

Fluoroquinolones

Question 21

Antacids ? the absorption of fluoroquinolones and should be taken at least two
hours after the drug

Answer 21

decrease

Question 22

Rifampin

Answer 22

inhibits RNA synthesis by inhibiting DNA-dependent RNA polymerase

Question 23

Only drug bactericidal to M. leprae
Effective in tuberculosis and atypical mycobacterial infections
Cutaneous leishmaniasis and rhinoscleroma

Answer 23

Rifampin

Question 24

orange-red discoloration

Answer 24

Rifampin

Question 25

Clindamycin MOA

Answer 25

• Binds to the 50S ribosomal subunit and inhibits protein

synthesis

Question 26

deep tissue infections anaerobic and gram-positive organisms

Answer 26

Clindamycin

Question 27

Pseudomembraneous colitis associated with Clostridium difficile

Answer 27

10% of treated patients Clindamycin