Antimicrobial Pharmacotherapy

Question 1

Example of drug that uses enzymatic inactivation as a mechanism of resistance

Answer 1

B-lactams (Penicillins), B-lactamases

Question 2

Example of drug that uses efflux pumps as a mechanism of resistance

Answer 2

Fluroquinolones (ciprofloxicin)

Question 3

Example of drug that uses changing in abx binding site as a mechanism of resistance

Answer 3

Vancomycin

Question 4

Example of drug that uses change in permeability as a mechanism of resistance

Answer 4

polymixins, daptomycin

Question 5

Penicillins

Answer 5

• MOA: bind to transpeptidase enzymes in the bacterial cell wall and disrupt cell wall formation
• Bactericidal

Question 6

Penicillin that has activity against pseudomonas

Answer 6

Piperacillin

Question 7

Penicillin that has activity against MSSA

Answer 7

Nafcillin and Dicloxacillin

Question 8

Penicillins that has activity against Gram - anaerobes

Answer 8

Augmentin, Unasyn, Tic/Clav, Pip/tazo

Question 9

Cephalosporins

Answer 9

• MOA; bind to transpeptidase enzymes in the bacterial cell and disrupt cell wall formation
• Same as pen
• Bactericidal
• As the generations inc so does the activity against gram negatives
• As the generations inc so does the activity against pseudomonas

Question 10

Cephalosporins that has activity against MSSA

Answer 10

Cefazolin (1st gen)

Question 11

Cephalosporins that has activity against pseudomonas

Answer 11

• Ceftazidime (3rd gen)

- Cefepime (4th gen)

Question 12

Cephalosporins that has activity against MRSA

Answer 12

Cefepime (5th gen)

Question 13

Carbapenems

Answer 13

• Most broad spectrum
• No MRSA coverage or atypicals
• Active against most gram neg aerobes including pseudomonas

Question 14

Aminoglycosides

Answer 14

• MOA: bind to the 30s ribosomal subunit and inhibit bacterial protein synthesis
• bactericidal
• Gentamicin is used in combo w/ other cell wall active agents for gram + IE
• Active against gram neg organisms including pseudomonas (Amikacin&raquo_space; tobra&raquo_space; gent vs pseudo)
• No activity against gram neg anaerobes
• AE: nephrotoxicity, ototoxicity, enhanced neuromuscular blockade

Question 15

Tetracyclines

Answer 15

• MOA: reversibly bind to the 30s subunit and inhibit bacterial protein synthesis
• bacteriostatic
• Oral absorption dec by admin w/ cations (milk, antacids)
  - Tetra»>doxy
• AE: GI intolerance, phototoxicity, fanconi syndrome
• Cover atypicals

Question 16

Macrolides

Answer 16

• MOA: reversibly bind to the 50s subunit and inhibit protein synthesis
• bacteriostatic
• Gram + aerobes (Erythro>clarithro>azithro)
• Gram - aerobes (Azithro>clarithro>erythro
• no pseudomonas activity or gram - anaerobes
• active against atypicals
• AE: GI intolerance

Question 17

Fluoroquinolones

Answer 17

• MOA: inhibit DNA gyrase which results in breakage of DNA
• bactericidal
• Oral absorption dec by admin with cations (milk)
• AE: GI intolerance, seizures, dizziness, QTc prolongation
• Not recomm. for children under 18 and pregnant women

Question 18

FQ with pseudomonas coverage

Answer 18

Cipro and levo

Question 19

First line drugs for Gram positive cocci

Answer 19

Pen, Amp, Amox

Question 20

First line drugs MSSA

Answer 20

Cefazolin

Question 21

First line drugs for MRSA

Answer 21

Vanco

Question 22

First line drugs for enterococcus

Answer 22

Amp + gent

Question 23

First line drug for gram neg bacilli

Answer 23

Ceftriaxone

Question 24

First line drugs for pseudomonas

Answer 24

pip/tazo + tobra, cefepime + tobra

Question 25

First line drugs for anaerobic gram neg bacilli

Answer 25

Clinda, metro