Abx III

Question 1

What are the abx that are clindamycins?

Answer 1

Clindamycin

Question 2

What is the use of clindamycin?

Answer 2

Narrow spectrum (strep and staph) used in the treatment of soft tissue infections

Question 3

What is the MOA of clindamycin?

Answer 3

Binds to 50s of the ribosomes and prevents the formation of initiation complex and translocation to the P site

Question 4

What are the key adverse effects of clindamycin?

Answer 4

GI: n/v

Question 5

What abx is highly associated with C.diff infections?

Answer 5

Clindmycin

Question 6

What type of abx is chloramphenicol?

Answer 6

Protein synthesis inhibitor

Question 7

What is the MOA of chloramphenicol?

Answer 7

binds to 50s subunit of the ribosome and present transpeptidation or peptidyl bond formation

Question 8

What are the two adverse effects of chloramphenicol?

Answer 8

Suppression of RBC production

Gray baby syndrome: infants lack acid conjugation

Question 9

What is gray baby syndrome, and what abx causes it?

Answer 9

The UDP-glucuronyl transferase enzyme system of infants, especially premature infants, is immature and incapable of metabolizing the excessive drug load.

Chloramphenicol level in blood is increased, at higher concentration chloramphenicol blocks electron transport in the liver, myocardium, and skeletal muscles

Question 10

What type of abx is linezolid?

Answer 10

Protein synthesis inhibitor

Question 11

What is the MOA of linezolid?

Answer 11

Inhibits protein synthesis by binding to the P site of the 50s ribosome and inhibiting the formation of the ribosomal tRNA complex (very first step in protein synthesis)

Question 12

What is linezolid used to treat?

Answer 12

Usually gram positive, and resistance organisms

Question 13

What are the three abx that are used for treating resistant organisms?

Answer 13

Vanco
Linezolid
Daptomycin

Question 14

What is the key adverse effect of linezolid?

Answer 14

Myelosuppression

Question 15

What is the protein synthesis abx that prevents that very first step in protein synthesis?

Answer 15

Linezolid

Question 16

What is the one protein inhibiting abx that is not broad spectrum? Which organisms does this treat?

Answer 16

Clindamycin

Gram positive cocci (MRSA)

Question 17

What are the three sulfonamides?

Answer 17

1. Sulfadiazine
2. Sulfamethoxazole
3. Sulfamethizole

Question 18

What is the MOA of sulfa drugs?

Answer 18

Structurally similar to PABA, a precursor for dihydrofolic acid. These compete with PABA for the enzyme dihydrofolate synthase

Question 19

What are sulfa drugs used to treat?

Answer 19

Broad spectrum for both gram positive and negative, but not usually used alone.

UTIs

Question 20

What are the three key adverse effect of sulfa drugs?

Answer 20

Skin hypersensitivity
Skin Photosensitivity
Steven-Johnson syndrome

Question 21

What are sulfa drugs usually combined with? Why?

Answer 21

Trimethoprim and pyrimethamine

Have synergistic effects

Question 22

What are the abx that are trimethoprim abx?

Answer 22

Trimethoprim

Pyrimethamine

Question 23

What are trimethoprim used to treat?

Answer 23

Gram negative in UTIs

Question 24

What is the MOA of trimethoprim?

Answer 24

Inhibit bacterial dihydrofolate reductase

Question 25

What are the adverse effects of trimethoprim?

Answer 25

Myelosuppression Megaloblastic anemia Leukopenia

Question 26

What is TMP-SMX?

Answer 26

Trimethoprim + sulfa drugs

Question 27

What are the adverse effects of TMP-SMX?

Answer 27

Same as for each agent alone

Question 28

What is the MOA of fluoroquinolones?

Answer 28

Disrupts the winding of DNA and the separation o DNA strands during transcription (topoisomerases and gyrases)

Question 29

What are the two major fluoroquinolones?

Answer 29

Ciprofloxacin | Levofloxacin

Question 30

What are fluoroquinolones used for?

Answer 30

UTI RTI gram + and gram _

Question 31

Anthrax treatment = ?

Answer 31

Fluoroquinolones

Question 32

What are the key adverse effects of fluoroquinolones?

Answer 32

n/v/d QT prolongation Tendonitis

Question 33

What is the nutritional problem that can arise with fluoroquinolones?

Answer 33

Binds divalent Cations (e.g. Ca) preventing absorption

Question 34

What type of abx will impair absorption of Ca?

Answer 34

Fluoroquinolones

Question 35

What type of abx is cipro?

Answer 35

Fluoroquinolone

Question 36

What are group 1 fluoroquinolones? What are significant about these?

Answer 36

Norfloxacin Least active fluoroquinolone

Question 37

What are group 2 fluoroquinolones? What bacteria are these useful for?

Answer 37

Cipro Levo Ofloxacin Gram negative

Question 38

What are group 3 fluoroquinolones? What bacteria are these useful for?

Answer 38

Gatifloxacin Gemifloxacin Moxifloxacin Gram positive

Question 39

What is the MOA of metronidazole?

Answer 39

Prodrug taken up by the organism that binds to DNA and disrupt function

Question 40

What does metronidazole treat (2)?

Answer 40

Anaerobic bacteria and protozoa

Question 41

Why can metronidazole only treat anaerobic bacteria?

Answer 41

ROS generation that would otherwise be degraded by aerobic activity

Question 42

What are the adverse effects of metronidazole?

Answer 42

n/v/d | Disulfiram effect

Question 43

What is the MOA of disulfiram? What is this used for?

Answer 43

Inhibits acetaldehyde dehydrogenase in the liver Used to treat alcoholics to induce bad effects with drinking EtOH

Question 44

What should you avoid when taking metronidazole?

Answer 44

EtOH

Question 45

What is the MOA of daptomycin?

Answer 45

Binds to the membrane and causes depolarization of the membrane and ultimately is bactericidal

Question 46

What is daptomycin used to treat?

Answer 46

gram positive organisms

Question 47

Is daptomycin bactericidal or bacteriostatic?

Answer 47

Bactericidal

Question 48

What is the key adverse effect of daptomycin?

Answer 48

Myopathy and rhabdomyolysis

Question 49

What is daptomycin usually used to treat?

Answer 49

Complicated soft tissue infections

Question 50

What is the MOA of polymyxin B?

Answer 50

binds to phospholipids in the cell membrane and disrupts structure (specifically LPS)

Question 51

Why is polymyxin B useful for gram negative organisms?

Answer 51

Punches hole in LPS

Question 52

What type of bacteria is polymyxin B used to treat?

Answer 52

Gram negative (specifically targets LPS)

Question 53

What is the key adverse effect of polymyxin B?

Answer 53

Rare if administered orally

Question 54

What are the three MOA of PCN/cephalosporin resistance?

Answer 54

1. Expression of beta lactamase 2. Alteration in PBP 3. ALteration in porin function

Question 55

What is the MOA of resistance against aminoglycosides?

Answer 55

Expression of enzymes that alter chemical structure of the drug

Question 56

What are the two MOA of resistance against Macrolides?

Answer 56

1. Transport of drug out of the cell | 2. ALterations of dug binding to the 50s ribosome

Question 57

What is the main MOA of resistance against tetracyclines?

Answer 57

Transport of drug out of cell

Question 58

What are the three MOAs of resistance against sulfonamides?

Answer 58

1. Less sensitive drug target 2. Increased synthesis of PABA 3. Scavenge folic acid

Question 59

What are the two MOAs of fluoroquinolones?

Answer 59

1. Less sensitive drug target | 2. Transport of drug out of cell

Question 60

What is the main MOA of resistance to chloramphenicol?

Answer 60

Expression of inactivating enzymes