Penicillin (Dr. Grim) - 9/1/15

Question 1

What gram (+) bugs are addressed with the natural penicillin class?

Answer 1

Group A, B, C, F, G Streptococci

Viridans streptococci

Question 2

What gram (-) bugs are addressed by the natural penicillin class?

Answer 2

Neisseria meningitidis

Question 3

What anaerobic bugs are addressed by the natural penicillin class?

Answer 3

Clostridium spp.

Question 4

Treponema pallidum (syphillus) is best treated with what class of penicillins?

Answer 4

Natural penicillins

Question 5

What gram (+) bugs are addressed with penicillinase-resistant penicillins? Eg. Nafcillin (IV) and Dicloxacillin (PO)

Answer 5

Methicillin-susceptible Staphylococcus aureus (MSSA)

“Naf for Staph”

Question 6

Name 2 aminopenicillins

Answer 6

Amipicillin (IV)

Amoxicillin (PO)

Question 7

What gram (+) bugs are addressed by aminopenicillins, such as ampicillin or amoxicillin?

Answer 7

Enterococcus

Listeria monocytogenes

Question 8

Name a drug in the carboxypenicillin class

Answer 8

Ticarcilin

Question 9

Ticarcilin (carboxypenicillin class) shows optimal activity for what bugs?

Answer 9

Mostly gram (-) bugs, such as:

Pseudomonas spp.
Stenotrophomonas maltophilia

Question 10

Name a drug in the ureidopenicillin drug class

Answer 10

Piperacillin (IV)

Question 11

Main use for peperacillin

Answer 11

Broad gram (-) coverage including P. aeruginosa

Question 12

Ampicillin + _______ for B-lactamase producing strains

Answer 12

sulbactam

Question 13

Amoxicillin + _______ for B-lactamase producing strains

Answer 13

clavulanate

Question 14

Piperacillin + _______ for B-lactamase producing strains

Answer 14

tazobactam

Question 15

_________ enhance the antibacterial activity of their companion penicillin in situations where the resistance is primarily the result of B-lactamase production.

Answer 15

B-lactamase inhibitors

Question 16

ALL penicillins have relatively short ______.

Answer 16

Elimination half-lives (

Question 17

Ampicillin and amoxicillin fall into WHAT CLASS of penicillins?

Answer 17

Aminopenicillins

Question 18

Aqueous penicillin G, benzathine penicillin G, procaine penicillin G, penicillin VK. What class are these?

Answer 18

“Natural” penicillins

Question 19

As an exception, penicillins show BACTERIOSTATIC activity against

Answer 19

Enterococcus spp.

Question 20

As exceptions, nafcillin and oxacillin are eliminated primarily by ________, whereas piperacillin undergoes __________

Answer 20

Liver, dual elimination (liver + kidney)

Question 21

B-lactamase inhibitors show enhanced activity against B-lactamase producing strains of what anaerobes?

Answer 21

B. fragilis and

B. fragilis group (DOT) organisms.

Question 22

B-lactams are bactericidal, or bacteriostatic?

Answer 22

Bactericidal (except in the case of Enterococcus spp)

Question 23

Bactericidal activity (via synergy) can be achieved against Enterococcus spp. by adding an __________.

Answer 23

Aminoglycoside (gentamicin or streptomycin)

Question 24

Do penicillins rely on binding proteins?

Answer 24

Wide range - it depends!

1. 15% binding for aminopenicillins
2. 97% for dicloxacillin

Question 25

Class of penicillins developed to further enhance activity against gram-negative bacteria. These agents are derived from the ampicillin molecule with acyl side chain adaptations that allow for greater cell wall penetration and increased PBP affinity.

Answer 25

Ureidopenicillins eg. Piperacillin

Question 26

Cross-allergenicity is observed between __________ due to their common nucleus

Answer 26

natural and semisynthetic penicillins

Question 27

Describe 3 primary mechanisms of resistance to penicillin antibiotics

Answer 27

1. B-lactamase enzymes 2. Altered PBP structure (decreasing affinity) 3. Antibiotic can't penetrate outer membrane of G- bacteria

Question 28

Example of a ureidopenicillin

Answer 28

Piperacillin

Question 29

Give an example of a carboxypenicillin drug

Answer 29

Ticarcillin

Question 30

In the case of inflammed meninges - how do you achieve adequate concentrations of penicillins?

Answer 30

High dose of parenteral

Question 31

MOST penicillins are eliminated unmetabolized primarily by the ________

Answer 31

kidneys (via glomerular filtration and tubular secretion)

Question 32

Most penicillins are removed during hemodialysis or peritoneal dialysis, and require supplemental dosing after a hemodialysis procedure. But what are the exceptions?

Answer 32

nafcillin and oxacillin

Question 33

Name 2 key penicillinase-resistant penicillins

Answer 33

1. Nafcillin 2. Dicloxacillin note: handout also mentioned methicillin (not avail anymore), and oxacillin. These weren't bolded.

Question 34

Natural penicillins have very little activity against

Answer 34

Staphylococcus spp. (gram +) due to penicillinase production

Question 35

Parenteral ampicillin is used for the treatment of_________ infections (with an aminoglycoside for endocarditis) and Listeria monocytogenes meningitis.

Answer 35

Enterococcal

Question 36

Penicillin G is still considered to be a DRUG OF CHOICE for the treatment of (~6)?

Answer 36

1. Treponema pallidum (syphilis***) 2. Neisseria meningitidis 3. Corynebacterium diphtheriae 4. Bacillus anthracis (anthrax) 5. Clostridium perfringens and tetani 6. viridans and Group Streptococci.

Question 37

Penicillins display ______-dependent bactericidal activity.

Answer 37

Time

Question 38

Piperacillin is the most active penicillin for infections due to _______

Answer 38

Pseudomonas aeruginosa.

Question 39

Piperacillin shows good activity against what gram-negative bug?

Answer 39

Pseudomonas aeruginosa

Question 40

Stenotrophomonas maltophilia is treated by penicillin combo with ____?

Answer 40

Ticarcillin/clavulanate

Question 41

The B-lactamase inhibitors ticarcillin/clavulanate are active against what bug?

Answer 41

Stenotrophomonas maltophilia

Question 42

The pharmacodynamic parameter that correlates with clinical efficacy of the penicillins is _____________

Answer 42

Time above the MIC

Question 43

This pharmacological consideration must be considered in patients with cardiac or renal dysfunction.

Answer 43

Na load

Question 44

Ticarcillin falls under what class of penicillin drug?

Answer 44

Carboxypenicillin

Question 45

Ticarcillin is an example of a drug with a very high ___________; be careful with cardiac and renal dysfunction patients.

Answer 45

Sodium load (5.2 mEq per gram)

Question 46

Ticarcillin is the drug of choice for?

Answer 46

Pseudomonas aeruginosa | Note: NOT active against Klebsiella spp., Serratia spp., or Actinobacter spp.

Question 47

Typical route of administration for penicillins

Answer 47

Parenteral (many are degraded by stomach acid)

Question 48

As exceptions, what 4 penicillin drugs are NOT eliminated via kidneys?

Answer 48

nafcillin oxacillin ceftriaxone cefoperazone

Question 49

The following penicillin drugs are exceptions to what rule? ceftriaxone, cefoperazone, cefotetan, cefixime, ertapenem

Answer 49

Unlike most penicillins, these don't have short elimination half-lives

Question 50

All penicillins exhibit cross-allergenicity between classes, except _________

Answer 50

aztreonam

Question 51

aztreonam is an exception to what rule, for penicillin drugs?

Answer 51

aztreonam does not exhibit cross-allerginicity between drug classes!