Antibiotics- Bacterial cell wall inhibitors

Question 1

What are penicillinase-susceptible, narrow spectrum penicillins?

Answer 1

1. Penicillin G
2. Penicillin VK*

*these are susceptible to penicillinase

Question 2

What are penicillinase-resistant, narrow spectrum penicillins?

Answer 2

Nafcillin*

Oxacillin

Question 3

Which antibiotics are classified as wider spectrum penicillins?

Answer 3

1. Ampicillin
2. Amoxicillin*
3. Piperacillin
4. Ticarcillin

Question 4

Pharmacokinetics of penicillin

Answer 4

• Rapid renal elimination
• Some biliary clearance of ampicillin and nafcillin

*don’t give in pediatric patients or patients with liver/gallbladder problems

Question 5

ADEs of penicillins

Answer 5

1. Hypersensitivity reactions***** (~5-6%incidence)
2. Maculopapular rash (ampicillin)

Question 6

Activity spectrum and clinical uses of narrow spectrum penicillins

Answer 6

• Streptococcal infections*
• Staphylococcal infections*
• Meningococcal infections
• Syphilis

*= highlighted in red on powerpoint

Question 7

Activity spectrum and clinical uses of wider spectrum penicillins

Answer 7

Greater activity vs. gram negative bacteria

Question 8

What are some first generation Cephalosporins?

Answer 8

Cephalexin (Keflex)

this is the narrowest spectrum and the oldest Cephalosporin- always want to try to use this first

Question 9

What are some second generation Cephalosporins?

Answer 9

1. Cefotetan (injectable)
2. Cefoxitin(injectable)
3. Cefuroxime*

*= bolded on powerpoint slide

Question 10

What are some third generation cephalosporins?

Answer 10

• Ceftriaxone* (injectable)
• Cefixime*
• Cefotaxime (injectable)
• Ceftazidime (injectable)

*= bolded on slide

Question 11

What are some fourth generation cephalosporins

Answer 11

Cefipime (injectable)

Question 12

Fifth generation cephalosporins

Answer 12

Ceftaroline (injectible)

5th generation= deiscovered most recently

Question 13

When should you not give cephalosporins

Answer 13

if patient has a penicillin allergy (anaphylaxis)

Question 14

Pharmacokinetics of cephalosporins

Answer 14

• Oral use for older drugs
• Mostly IV for newer drugs
• Renal elimination
• Third-generation drugs enter CNS****

Question 15

ADEs of cephalosporins

Answer 15

• Hypersensitivity reactions (~2% incidence)
• Assume complete cross-reactivity between cephalosporins**
• First generation partial cross-reactivity with penicillins***

Question 16

What cephalosporin is not given to newborns and why?

Answer 16

Ceftriaxone is contraindicated in neonates because it displaces bilirubin from albumin binding sites, resulting in a higher free bilirubin serum concentration with subsequent accumulation of bilirubin in the tissues.

Also precipitates calcium

Question 17

What is the activity spectrum and clinical uses of 1st generation cephalosporins?

Answer 17

skin

soft tissue

UTI

Question 18

What is the activity spectrum and clinical uses of 2nd generation cephalosporins?

Answer 18

More active against S. pneumoniae and H influenza

B fragilis (cefotetan)

Question 19

What is the activity spectrum and clinical uses of 3rd generation cephalosporins?

Answer 19

• Many uses including pneumonia, meningitis, and gonorrhea
• Broad activity, beta-lactamase-stable

Question 20

What is the activity spectrum and clinical uses of 4th generation cephalosporins?

Answer 20

Pseudomonas coverage

Question 21

What is the activity spectrum and clinical uses of 5th generation cephalosporins?

Answer 21

Skin

soft tissue

CAP (community acquired pneumonia)

Question 22

_____ generation cephalosporins may exhibit cross sensitivity with ____

Answer 22

First, Penicillins

First generation cephalosporins were found to be contaminated with penicillin in the past, probably explaining cross-reactivity in penicillin-allergic patients

Question 23

Is there cross reactivity in 2nd-5th generation cephalosporins with penicillins?

Answer 23

these can usually be given safely to penicillin-allergic patients, though commonly witheld if the patient suffered true penicillin-induced anaphylaxis

Question 24

Cephalosporin cross sensitivity with penicillins- delayed dermatologic reactions vs. Type I hypersensitivty rxns

Answer 24

Delayed dermatologic rxns (i.e. rash) to penicillin generally can receive cephalosporins

However, Type I hypersensitivity rxns (anaphylaxis) to penicillins should not receive cephalosporins

Question 25

What are some alternatives to cephalosporins if the patient is penicillin allergic?

Answer 25

Aztreonam quinolones sulfonamide antibiotics vancomycin

Question 26

What is the rule of thumb for giving cephalosporins to patients allergic to penicillin in the absence of complete penicillin skin testing capabilities?

Answer 26

Avoid giving cephalosporins to patients who give a good history for immediate or accelerated rxns (eg, anaphylaxis, laryngospasm) and to give them under close supervision to patients with a hx of delayed rxns (rash)

Question 27

What antibiotic should be given if a gram-negative infection is suspected or documented?

Answer 27

Therapy with a monobactam may be appropriate because cross reactivity with other B-lactams is nonexistent

Question 28

ADEs of Carbapenems

Answer 28

These are beta-lactams so they have similar structure to penicillins and cephalosporins They have a broad spectrum of activity but have **CNS adverse effects** including **confusion and seizures** (this is why carbapenems are different than B lactams)

Question 29

Types of Carbapenems

Answer 29

Imipenem-cilastatin (Primaxin)\* Dorpenem Meropenem Ertapenem \*= bolded on slide

Question 30

What do Carbapenems treat?

Answer 30

They are broad spectrum - Some PRSP (Penicillinase resistant srep pneumoniae) but not MRSA - Gram negative rods - Pseudomonas sp

Question 31

Monobactam

Answer 31

This is beta-lactam -does NOT have cross allergenicity with other beta-lactams

Question 32

What is an example of a Monobactam?

Answer 32

Aztreonam \*No cross-allergenicity with beta-lactams

Question 33

What are Monobactams active against?

Answer 33

They are active only vs. gram-negative bacteria: 1. Klebsiella 2. Pseudomonas 3. Serratia spp

Question 34

ADEs of Monobactam

Answer 34

CNS: Headache, vertigo

Question 35

\_\_\_\_\_\_\_\_ is a glycopeptide that covers MRSA and PRSP

Answer 35

Vancomycin

Question 36

What are vancomycin agents?

Answer 36

1. Vancomycin\* 2. Dalbavancin 3. Oritavancin 4. Telavancin 2-4 are primarily for skin and skin structure infections; Telavancin is also used for hospital acquired and ventilator associated bacterial pneumonia

Question 37

What are the pharmokinetics of Vancomycin?

Answer 37

- Parenteral for systemic infections - oral vancomycin for C. diff colitis - renal elimination

Question 38

How do you treat C. diff?

Answer 38

ORAL vancomycin (IV vancomycin will NOT tx C. diff)

Question 39

What are toxicities of vancomycin?

Answer 39

* Red-neck or red man syndrome (Erythematous rash on face and upper body--\> Infusion rate cause and not an allergic reaction) * Rare nephrotoxicity

Question 40

What is the activity spectrum of vancomycin?

Answer 40

Gram positive activity includes MRSA and PRSP strains

Question 41

Daptomycin

Answer 41

Daptomycin is a lipopeptide with activity against MSSA and MRSA Agent: Daptomycin

Question 42

Pharmacokinetics of Daptomycin

Answer 42

renal elimination

Question 43

Toxicities of Daptomycin

Answer 43

Myopathy (this is a unique toxicity) Must monitor CPK (Creatinine kinase) weekly

Question 44

What is the activity spectrum of Daptomycin?

Answer 44

1. Gram-positive activity 2. Endocarditis and sepsis\* 3. Off-labeled uses- osteomyelitis and prosthetic joint infections 4. MSSA and MRSA coverage