Protein Synthesis Inhibitors

Question 1

3 Tetracycline drugs

Answer 1

Tetracycline, doxycycline, minocycline

Question 2

Tetracyclines
Mechanism:
Spectrum:

Answer 2

reversible binding to 30S

Very broad

Question 3

Tetracycline
Distribution:
Accumulation?
CNS penetration?

Answer 3

Wide
Bone, dentine, enamel as calcium chelates
Good CNS penetration

Question 4

Tetracyclines mostly excreted through ____

EXCEPT:

Answer 4

Kidneys
Doxycycline: eliminated as inactive chelate in feces → good for pt w/ renal dysfuntion
Minocycline: Passed in feces

Question 5

Tetracyclines main adverse effects (3)

Answer 5

GI irritation and superinfection
Discoloration of teeth
Fetal and childhood risks → do not give to pregnant women or children

Question 6

Contraindication to Tetracyclines:

Answer 6

o *Flibanserin, lomitapide: increase other drug levels by altering hepatic/intestinal CYP3A4
o Digoxin: increase levels via changes in intestinal flora, reduced metabolism
o *Tretinoin & Acitretin: increase intracranial pressure

Question 7

Effective against strains that are tetracycline resistant, Some MRSA
Treat skin, intra abdominal infections

Answer 7

Tigecycline

Question 8

Gentamicin

Type of drug:

Answer 8

Aminoglycoside

Question 9

Aminoglycoside
Mechanism:
Bactericidal or bacteriostatic?

Answer 9

Binds irreversibly to 30S
Concentration-dependent killing w/ significant PAE
Bactericidal even though its a protein synthesis inhibitor

Question 10

Aminoglycoside
Spectrum:
Combo therapy w/ ___(2) to work against ____

Answer 10

Gram - aerobic bacilli
PCN, vancomycin
Straphylococcus aureus, S. epidermidis

Question 11

Aminoglycoside

Distribution:

Answer 11

High concentration in inner ear and renal cortex –> toxicity

Question 12

Gentamicin used for ___

Answer 12

Severe Gm- infections

Question 13

Used for antibiotic resistant gonorrhea

Answer 13

Spectinomycin

Question 14

Spectinomycin

Bacteriocidal or bacteriostatic?

Answer 14

Bacteriostatic

Question 15

Macrolids

Bacteriocidal or bacteriostatic?

Answer 15

Bacteriostatic

Question 16

Exhibits antagonism by competitively inhibit ribosome binding of streptogramins, clindamycin, chloramphenicol

Answer 16

Macrolides

Question 17

MLS-type B resistance caused by methylase modifying bacterial ribosome so that drug can’t bind is seen the major drawback of this drug

Answer 17

Macrolide, Lincosamides, Streptogramin

Question 18

Erythromycin

Acid labile or stable?

Answer 18

Acid labile.

All other macrolides are acid stable

Question 19

Macrolide distribution

Answer 19

wide

Erytromycin penetrates into abscesses

Question 20

Good alternative to PCNs, especially for allergic patients

Answer 20

Macrolide

Question 21

All Macrolides exhibit drug interactions by inhibiting CYP3A4 EXCEPT ___

Answer 21

Azithromycin: structurally unique

Question 22

Main adverse effects of macrolides (2)

Answer 22

GI disturbances

Cholestatic hepatitis

Question 23

This drug will exacerbate of disease symptoms in myasthenia gravis patients

Answer 23

Ketolides: Telithromycin

Question 24

Telithromycin

Bacteriocidal or bacteriostatic?

Answer 24

Bacteriostatic

Question 25

Telithromycin | Mechanism of action

Answer 25

Binds 50S ribosome at 2 sites

Question 26

Used for community acquired RTIs (pneumonia), acute bacterial sinusitis, chronic bronchitis

Answer 26

Ketolides: Telithromycin

Question 27

Chloramphenicol | Mechanism of action:

Answer 27

Binds reversibly to 50S ribosome | *Near binding of clindamycin and macrolides

Question 28

Chloramphenicol | Spectrum:

Answer 28

*Broad Most anaerobic bacteria Most Gm- bacilli

Question 29

Chloramphenicol | Biggest problem:

Answer 29

Resistance caused by acetyltransferases modifying drug

Question 30

Clinical uses restricted due to toxicity for this drug

Answer 30

Chloramphenicol

Question 31

Major adverse effect of Chloramphenicol

Answer 31

Gray Baby Syndrome: can't metabolize drug

Question 32

Prolongs half-life of drugs metabolized by CYPs

Answer 32

Drug interaction of Chloramphenicol

Question 33

Quinupristin/dalfopristin | Bactericidal or bacteriostatic?

Answer 33

Bactericidal | Individually: bacteriostatic

Question 34

Quinupristin/dalfopristin | Clinical uses

Answer 34

MRSA | Vancomycin resistant Gm+ infections: VREF, VRSA, Streptococcus pneumoniae

Question 35

No cross resistance with other protein synthesis inhibitors

Answer 35

Linezolid

Question 36

Binds novel site in 23S ribosomal RNA of 50S ribosomal subunit

Answer 36

Linezolid: Clindamycin

Question 37

Drug of choice for respiratory tract infections caused by anaerobes

Answer 37

Clindamycin

Question 38

Used for MRSA, Osteomyelitis, Abscesses, Severe Group A Strep infections

Answer 38

Clindamycin

Question 39

Adverse effects of Clindamycin

Answer 39

Pseudomembranous colitis

Question 40

Topical use only | Treat impetigo caused by MRSA or Group A Strep

Answer 40

Mupirocin

Question 41

Mupirocin mechanism of action:

Answer 41

Inhibit isoleucyl tRNA synthetase