Protein Synthesis Inhibitors

Question 1

What are the aminoglycs?

Answer 1

Gentamicin, Neomycin, Amikacin (Amikin), Tobramycin, Streptomycin (GNATS)

Question 2

MOA Aminoglycs?

Answer 2

Inhibit formation of initiation complex and cause misreading of mRNA, blocks translocation

Question 3

What are aminoglycs specifically ineffective at covering? Why?

Answer 3

Anaerobes b/c require O2 for uptake

Question 4

Aminoglyc coverage?

Answer 4

Severe G- rod

Question 5

Which aminoglyc is used for boweel surgery?

Answer 5

Neomycin

Question 6

Toxicity of Aminoglycs

Answer 6

Nephrotox, Neuromsk blockade, ototox, teratogen

Question 7

Aminoglyc MOR

Answer 7

Bacterial transferase enzymes inactivate drug by acetylation, phosph, or adenylation

Question 8

What are the tetracyclines?

Answer 8

Tetracycline (Sumycin), doxycycline , minocycline

Question 9

MOA of Tetracyclines?

Answer 9

Bind to 30S and prevent attachment of aminoacyl-tRNA

Question 10

What is a limit of tetracyclines?

Answer 10

Limited CNS penetration

Question 11

A pt w/ which comorbidity should doxy be used? Why?

Answer 11

Fecally eliminated - can be used in renal failure,

Question 12

Dietary restrictions when taking tetracyclines?

Answer 12

No milk or antacids or iron-containing preps b/c they decrease absorption in gut

Question 13

Clinical use of tetracyclines?

Answer 13

B. burgdorferi, M. pneumoniae, Rickettsia, Chlamydia

Question 14

Why are tetras so effective against Rickettsia and Chlamydia?

Answer 14

Good intracellular accumulation

Question 15

Contraindications to tetracycline use?

Answer 15

Children, pregnant women (Teeth discoloration and teratogenicity)

Question 16

MOR tetracyclines?

Answer 16

Decreased uptake/Increased efflux via plasmid-encoded pump

Question 17

What are the Macrolides?

Answer 17

Azithromycin (Zithromax), Clarithromycin (Biaxin), erythromycin

Question 18

MOA of Macrolides?

Answer 18

Inhibit protein synth by blocking translocation; bind to 23S rRNA of 50S ribosomal subunit

Question 19

Macrolide coverage?

Answer 19

Atypical pneumonias (Mycoplasma, Chlamydia, Legionella), G+ cocci (Strep infections in patients allegic to penicillin)

Question 20

Macrolide toxicity?

Answer 20

GI motility issues, Arrhythmia caused by prolonged QT, acute cholestatic hepatitis, eosinophilia, Rash

Question 21

Cross-reactivity of Macrolides?

Answer 21

Increases serum conc of theophyllines, and oral anticoags

Question 22

MOR of macrolides?

Answer 22

Methylation of 23S rRNA-binding site prevents binding of drug

Question 23

To what class does Clindamycin (Cleocin) belong?

Answer 23

Clindamycin

Question 24

MOA of Clindamycin

Answer 24

Blocks peptide transfer (translocation) at 50S ribosomal subunit

Question 25

Clindamycin coverage?

Answer 25

Anaerobes (Bacteroides spp, Clostridium perfringens), in aspiration pneumo, lung abscesses, and oral infections, effective against invasive GAS infection

Question 26

Tx of anaerobes above diaphragm vs anaerobes below diaphragm

Answer 26

Clinda and metronidazole respectively

Question 27

Common SE of Clinda?

Answer 27

C. diff