Protein Synthesis

Question 1

• Selectively inhibit bacterial protein synthesis
• Protein synthesis in microorganisms is not identical to **mammalian **
  cells
• **70S **ribosomes in **bacteria **
• 80S ribosomes in mammalians

Answer 1

Protein Synthesis Inhibitors

Question 2

MECHANISM OF ACTION

Answer 2

• Bacteriostatic
• Bactericidal – Oxazolidinones and Pleuromutilins

Question 3

BACTERIAL PROTEIN SYNTHESIS INHIBITORs

• Chloramphenicol
• Tetracyclines

Answer 3

Broad spectrum

Question 4

BACTERIAL PROTEIN SYNTHESIS INHIBITORS

• Macrolides
• Ketolides

Answer 4

Moderate spectrum

Question 5

BACTERIAL PROTEIN SYNTHESIS INHIBITORS

• Lincosamides
• Streptogramins
• Linezolid

Answer 5

Narrow spectrum

Question 6

• **Simple **and **Distinctive structure **
• Effective Orally and Parenterally
• MOA: Inhibits microbial protein synthesis and is bacteriostatic against most susceptible organisms.
• It binds reversibly to the 50S subunit of the bacterial ribosome and inhibits peptide bond formation

Answer 6

Chloramphenicol
Chlo/ram/phe/ni/col

Question 7

Antimicrobial Activity

• **Broad spectrum **
• Active against both aerobic and anaerobic gram-positive and gram- negative organisms.
• Bacteriostatic
• Bactericidal - strains of H, influenzae, N. meningitidis, and some strains of Bacteroides
• Not active against Chlamydia species.
• Resistance is plasmid-mediated
• formation of chloramphenicol acetyltransferases

Answer 7

Chloramphenicol

Question 8

Absorption : TETRACYCLINE

• 60-70%
• Administered on an empty stomach.

Answer 8

• Tetracycline
• Demeclocycline

Question 9

Absorption : TETRACYCLINE

• 95-100%
• Not impaired by food.

Answer 9

• Doxycycline
• Minocycline

Question 10

Absorption : TETRACYCLINE

• 35%
• Absorption is impaired by:
  Multivalent cations (Ca2+, Mg2+, Fe2+, Al3+)
  Dairy products
  Antacids (contain multivalent cations)
  Alkaline pH

Answer 10

Omadacycline

Question 11

Tetracycline

It is Given IV

Answer 11

• Tigecycline
• Eravacycline

Question 12

Tetracycline

Question 13

Tetracycline

Excretion ?

Answer 13

Feces

Question 14

Tetracycline

Wide tissue distribution except in ?

Answer 14

CSF

Question 15

Tetracycline

Question 16

Tetracycline

Question 17

Tetracycline

Question 18

Tetracycline

Question 19

Tetracycline

Question 20

Tetracycline

Question 21

Tetracycline

Short-acting
6-8 hours serum half-life

Answer 21

• Tetracycline
• Chlortetracycline
• Oxytetracycline

Question 22

Tetracycline

Intermediate-acting
12 hours

Answer 22

Demeclocyline

Question 23

Tetracycline

Long-acting
16-18 hours

Answer 23

• Once daily: Doxycycline, Minocycline
• By convention, usually administered twice daily

Question 24

Tetracycline

Long half-lives
36, 20, and 16 hours (respectively)

Answer 24

1. Twice-daily dosing:
   * Tigecycline
   * Eravacycline
2. Once daily:
   * Omadacycline

Question 25

# Tetracycline What is the MOA ? Tetracycline Chlortetracycline Oxytetracycline

Answer 25

Oral

Question 26

# Tetracycline What is the MOA ? Demeclocyline

Answer 26

Oral

Question 27

# Tetracycline What is the MOA ? Doxycycline

Answer 27

Oral

Question 28

# Tetracycline What is the MOA ? Tigecycline Eravacycline

Answer 28

IV

Question 29

# Tetracycline What is the MOA ? Minocycline

Answer 29

IV

Question 30

# Tetracycline What is the MOA ? Omadacycline

Answer 30

Oral and IV

Question 31

# Tetracycline Primary uses

Answer 31

* Mycoplasma pneumoniae (in adults) * Chlamydiae, including STIs * Rickettsiae * Borrelia sp. * Vibrios (Vibrio cholerae) * Some spirochetes * Anaplasma phagocytophilum * Ehrlichia sp

Question 32

# Tetracycline Secondary uses

Answer 32

**Alternative :** * Community-acquired pneumonia (CAP) * Syphilis * Chronic bronchitis * Leptospirosis * Acne

Question 33

In-vitro activity against: MRSA ESBL-producing Gr(-)’s Acinetobacter sp

Answer 33

Tigecycline

Question 34

* Non Inferiority to: Moxifloxacin in the treatment of community-acquired bacterial pneumonia Linezolid in the treatment of acute bacterial skin and skin structure infections * Not affected by the most common resistance mechanisms; retains ​​activity against a broad array of pathogens resistant to older drugs. * Co-administration with any food leads to substantial decreases in the absorption of the oral form, it must be administered at least 4 hours after and 2 hours before any food or liquid other than water.

Answer 34

Omadacycline

Question 35

# Tetracycline Toxicity

Answer 35

1. GI disturbances : * Nausea, vomiting, and diarrhea * Tigecycline: Nausea * Esophageal ulceration (rare) * Life-threatening enterocolitis * Oral and vaginal candidiasis * Renal toxicity - Tetracyclines, especially demeclocycline * Photosensitivity - Tetracyclines, especially Demeclocycline * Vestibular toxicity - Doxycycline and minocycline

Question 36

# MACROLIDES : ERYTHROMYCIN, AZITHROMYCIN, CLARITHROMYCIN Prototype

Answer 36

Erythromycin

Question 37

Semisynthetic derivatives of erythromycin are ?

Answer 37

* Clarithromycin * Azithromycine

Question 38

Macrolides is what s ?

Answer 38

50s

Question 39

Macrolide antibiotics prolong ?

Answer 39

the electrocardiographic QT interval

Question 40

Torsades de Pointes arrhythmia.

Answer 40

Macrolides

Question 41

# Macrolides Good oral bioavailability.

Answer 41

Azithromycin

Question 42

# Macrolides absorption is impeded by food.

Answer 42

Azithromycin

Question 43

# Macrolides Distributed to most body tissues.

Answer 43

Azithromycin

Question 44

Macrolides is primarily what metabolism ?

Answer 44

Hepatic Metabolism.

Question 45

# macrolides 2 hours half-life

Answer 45

Erythromycin

Question 46

# macrolides 2 - 4 Days

Answer 46

Azithromycin

Question 47

# macrolides 6 Hours

Answer 47

Clarithromycin