30 S Protein Synthesis Inhibitors

Question 1

30s

Answer 1

AT

Aminoglycosides
Tetracyclines

Question 2

50s

Answer 2

Chloramphenicol
Erythromycin (Macrolides)
Lincosamides (Clindamycin)
Linezolid
Streptogramins

Question 3

All bacterial protein synthesis inhibitors are BACTERIOSTATIC EXCEPT

Answer 3

Aminoglycosides
Streptogramins
Chloramphenicol

Question 4

AMINOGLYCOSIDES

(-) protein synthesis at the 30s ribosomal subunits

SYNERGISTIC w/ beta lactam antibiotics and vancomycin (1+1 = 3)

Answer 4

Neomycin
Tobramycin
Gentamicin
Streptomycin
Kanamycin
Amikacin

“mycin” - from StreptoMYces
“micin” - from MICrominospora

Question 5

Most OTOTOXIC aminoglycosides

Answer 5

You will not hear my NAK

NEOMYCIN
KANAMYCIN
AMIKACIN

Question 6

Most VESTIBULOTOXIC aminoglycosides

Answer 6

Si SG laging naka VEST

STREPTOMYCIN
GENTAMICIN

TOBRAMYCIN

Question 7

Most NEPHROTOXIC aminoglycosides

Answer 7

NEOMYCIN
TOBRAMYCIN
GENTAMICIN

Question 8

MOA - Aminoglycosides

Answer 8

bind to the 30s ribosomal subunit and interfere w/ protein synthesis:

• block formation of the initiation complex
• cause misreading of the code on the MRNA template
• (-) translocation

Question 9

Limited to TOPICAL and ORAL use

Answer 9

Neomycin

Question 10

Aminoglycosides + B lactam antibiotics - SYNERGISM

if given SEQUENTIALLY

Answer 10

do NOT mix w/ B lactam in same solution

• nucleophilic opening of the B lactam ring
• acylation of the amino group of the aminoglycosides

Question 11

What is the MOST TOXIC AMINOGLYCOSIDES

Answer 11

TOBRAMYCIN

Question 12

Aminoglycosides - with ANTAGONISM with other bacteriostatic antibiotics

bacteriostatic + bactericidal = NO NO NO
1+1 = 0

Answer 12

d.t.
(-) of energy dependent uptake of aminoglycosides

interference w/ movement of the ribosome along mRNA

Question 13

BacterioSTATIC

prevents aminoacyl-tRNA from binding to acceptor site ribosome mRNA complex

Answer 13

TETRACYCLINE

Question 14

TETRACYCLINES

(+) naphthacene rings

Answer 14

SHORT ACTING

• Tetracycline
• Chlortetracycline
• Oxytetracycline

INTERMEDIATE ACTING

• Demeclocycline
• Methacycline

LONG ACTING

• Doxycline
• Minoxycline

Question 15

All tetracyclines are excreted renally EXCEPT

Answer 15

Doxycycline - BILE

Question 16

Absorption of tetracyclines are impaired by foods (antacids, dairy products, divalent cations - Ca, Mg, Fe) EXCEPT

BAWAL D.T.
COMPLEX FORMATION/CHELATION
*tetracycline ring gets attached to divalent cations – locked tetracycline structure – making it UNABSORBABLE

wait for 2-3 hrs bago mag milk or etc

Answer 16

Doxycycline

Minocycline

Question 17

Aminoglycosides coverage

Answer 17

gram (+) EXCEPT Strep pneumoniae
gram (-)
Pseudomonas
M. tuberculosis - STREPTOMYCIN
NO COVERAGE for atypical and anaerobic

Question 18

Tetracyclines coverage

Answer 18

BROADEST SPECTRUM ANTIBIOTIC

gram (+)
gram (-)
atypical organisms - Legionella, Chlamydophila, Mycoplasma
anaerobic organisms

NO COVERAGE against Pseudomonas

Question 19

Tetracycline that covers everything but stops at 3PM

Pseudomonas
Proteus
Providencia
Morganella

Answer 19

TIGECYCLINE - pero powerful na to ha

Question 20

Adverse Effects - Tetracycline

Answer 20

PERMANENT TEETH DISCOLORATION and ENAMEL HYPOPLASIA

bone deformity/growth retardation

AVOID during PREGNANCY and CHILDREN < 8 y/o

GI disturbances

Question 21

Tetracycline used for SIADH

Answer 21

Demeclocycline

Question 22

Tetracycline used for CAP and Bronchitis

Answer 22

Doxycycline

Question 23

Aminoglycosides used for RESISTANT GONORRHEA

Answer 23

Spectinomycin

Question 24

Aminoglycosides used for visceral leishmaniasis

Answer 24

Paromomycin

Question 25

LEAST RESISTANT Aminoglycosides but NARROWEST therapeutic window

Answer 25

Amikacin

Question 26

Resistance to STREPTOMYCIN develops d.t.

Answer 26

Changes in the RIBOSOMAL BINDING SITE