Antibiotics Lecture 34

Question 1

Clindamycin 
cidal or static 
MOA
Spectrum
Clinical Use
Adverse Effects
MOR

Answer 1

50S

Static (can be cidal at high concentrations)

1. Gram Positive
   - skin infection and soft tissue
   - CA-MRSA
   - penicillin allergy
2. Anaerobes***
   -Clostridium Perfringens
   -Bacteroides spp.
   -excludingXXX CNS
   -in aspiration, pneumonia, lung abscesses and oral infections
   (above diaphragm)

Side Effects
1. C-diff

MOR:
1. erm gene altered (clinda, macrolides, and synercid)

Question 2

Macrolides
Drugs 
cidal or static 
MOA
Spectrum
Clinical Use
Adverse Effects
MOR

Answer 2

1. Erythromycin
   better:
2. Clarithromycin
3. Azithromycin

Inhibit proteins synthesis by reversibly binding to 50S ribosomal subunit

Static (cidal high concentrations)

1. Gram positive aerobes
   - penicillin allergic
2. Gram negative
   - pertussis
3. Anaerobes-upper airway
4. Atypical bacteria***
   - Legionella
   - Chlamydia (STD)
   - Mycoplasma
5. uncomplicated skin infections

MOR:

1. efflux mef
2. erm altered binding site (clinda, macro, and synercid)

Toxicity:
M: motility 
A: arrhythmia prolonged QT **
C: Cholestatic hepatitis 
R: Rash
O: eosinophilia 
-Colchicine--Potentially fatal drug interaction 
-transient reversible deafness or tinnitus

Question 3

Which two macrolides display time dependent activity?

Answer 3

Erythromycin and clarithromycin

Question 4

Which macrolides treat H. Flu and MAC?

Answer 4

Azithro and clarithro

Question 5

What is the order to how effective certain macrolides are to gram positive aerobes?

Answer 5

1. Clarithro
2. Erythro
3. Azithro

Question 6

What is the order to how effective certain macrolides are to gram negative aerobes?

Answer 6

1. Azrithro
2. Clarithro
3. Erythro

Question 7

Which macrolides inhibit cytochrome P450 system in the liver? And what else inhibits it?

Answer 7

Erythromycin and Clarithromycin

Synercid

Question 8

What is quinupristin and dalfopristin-Synercid? What is it used for?

Answer 8

Streptogramins

VRE

Question 9

Synercid
MOA
MOR
Adverse side effects

Answer 9

50 S
-static ???
PAE

1.Gram positive bacteria
VRE bacteremia

MOR:

1. erm binding site
2. enzymatic inactivation

Toxicity:
1. Venous irritation