Miscellaneous

Question 1

What do chloramphenicol target?

Answer 1

IV for aerobic/anaerobic G+/G- microbes

Question 2

What sort of infections will chloramphenicol be used for?

Answer 2

Serious & fatal blood dycrasias (only seriously resistant infections)

Question 3

What is the mechanism of chloramphenicol?

Answer 3

Inhibits binding of ammoniacal-tRNA to acceptor site

Question 4

What is the main problem with using chloramphenicol?

Answer 4

Inhibits human mitochondrial peptidyl-transferase

Question 5

What cells are most sensitive to chloramphenicol?

Answer 5

Erythropoietic cells (leukopenia, thrombocytopenia, fatal aplastic anemia)
Causes a decrease in G6PD which predisposes you to hemolytic anemia

Question 6

What is gray baby syndrome caused by?

Answer 6

1) insufficient glucuronyl transferase (can’t conjugate)

2) underdeveloped renal function (can’t eliminate)

Question 7

What does chloramphenicol inhibit?

Answer 7

cytochrome P450

Question 8

Levels of chloramphenicol increase and interfere with mitochondrial ribosomes resulting in what?

Answer 8

Depressed respiration
CV Collapse
Cyanosis

Question 9

What do quinupristin/dalfopristin treat?

Answer 9

IV for MRSA and vancomycin-resistant infections

Question 10

What is the mechanism of quinupristin?

Answer 10

Releases peptidyl-tRNA from donor site

Question 11

What is the mechanism of Dalfopristin?

Answer 11

Inhibits binding of ammoniacal-tRNA to acceptor site & of peptidyl-tRNA to donor site

Question 12

Quinupristin/dalfopristin inhibits CYP3A which causes what?

Answer 12

Decreased metabolism of warfarin

Question 13

What are the side effects of quinupristin/dalfopristin?

Answer 13

Arthralgias/myalgias (30-40%)
Superinfection (colitis)
Hyperbilirubinemia (25%)
Severe venous irritation
Vancomycin-resistant E. faecium

Question 14

What is linezolid?

Answer 14

An oxazolidinone

Question 15

What is linezolid used for?

Answer 15

Vancomycin resistant E. faecium, MSSA & MRSA, skin infections (static or cidal)

Question 16

How can linezolid be administered?

Answer 16

Oral and IV

Question 17

What are the risks of linezolid?

Answer 17

Colitis and thrombocytopenia

Question 18

Is there a limit to how much you should use linezolid?

Answer 18

Do not use for more than 28 days

Question 19

What is the mechanism of linezolid?

Answer 19

Inhibits formation of the initiation complex

Question 20

What does linezolid inhibit and what might that cause?

Answer 20

Inhibits MAO-A which may cause 5HT syndrome if with other Rss that have increased 5HT activity

Question 21

What happens if you use linezolid chronically?

Answer 21

Reversible optic neuropathy
Irreversible peripheral neuropathy
Lactic acidosis

Question 22

What is tedizolid?

Answer 22

An oxazolidinone Pro-Rx

Question 23

How is tedizolid administered and what for?

Answer 23

Oral or IV for ABSSSI, including MRSA

Question 24

What is the mechanism of tedizolid?

Answer 24

Binds 50S ribosomal subunit resulting in inhibited protein synthesis

Question 25

What are the side effects of tedizolid?

Answer 25

Nausea, Vomiting, Diarrhea, Headache

Question 26

What are you at risk for when taking clindamycin?

Answer 26

Pseudomembranous colitis caused by opportunistic C. difficile

Question 27

What tissues does clindamycin penetrate well?

Answer 27

Everything except the CNS

Question 28

What is the mechanism of clindamycin?

Answer 28

Inhibits translocation

Question 29

What can clindamycin be used with to treat group A strep?

Answer 29

A high dose PCN

Question 30

What does polymyxin target and how?

Answer 30

G- microbes, it is a cidal cationic detergent

Question 31

What is polymyxin used for?

Answer 31

Common infections of the conjunctiva and lids (topical; rarely IV)

Question 32

What are the side effects of polymyxin?

Answer 32

Nephrotoxic and neurotoxic (neuromuscular block)

Question 33

What is colistimethate?

Answer 33

polymyxin E | A cidal cationic detergent

Question 34

What is colistimethate used for?

Answer 34

IV/IM for G- rods

Question 35

What are the side effects of colistimethate?

Answer 35

Nephrotoxic and possibly neurotoxic

Question 36

What is something interesting about rifaximin?

Answer 36

No significant systemic absorption

Question 37

What are the uses of rifaximin?

Answer 37

Travelers diarrhea from noninvasive strains of E. coli | Reduce risk hepatic encephalopathy in patients w/ advanced liver disease

Question 38

What is the rationale behind rifaximins effect of reducing hepatic encephalopathy?

Answer 38

Reduces ammonia producing bacteria

Question 39

What is the mechanism of rifaximin?

Answer 39

Binds DNA-dependent RNA polymerase

Question 40

What are the side effects of rifaximin?

Answer 40

Flatulence, abdominal pain, urgency to defecate

Question 41

What infection has developed cross resistance to rifaximin?

Answer 41

Staph

Question 42

What forms does mupirocin come in?

Answer 42

Ointment and cream

Question 43

What is the mechanism of mupirocin?

Answer 43

Inhibits bacterial isoleucyl t-RNA synthetase

Question 44

What is mupirocin used for?

Answer 44

Used for impetigo from group A strep or S. aureus (high resistance)

Question 45

What forms does retapamulin come in?

Answer 45

Topical ointment

Question 46

What does retapamulin do to impegito?

Answer 46

It is a pleuromutilin meaning it blocks protein synthesis

Question 47

What is the mechanism of retapamulin?

Answer 47

Blocks acceptor and donor sites of peptidyl-transferase

Question 48

What is nitrofurantoin used for?

Answer 48

Treatment and prevent G+/G- UTIs | Has poor systemic levels but lots of local action in tubules

Question 49

What is the mechanism of nitrofurantoin?

Answer 49

Reduced by urinary bacteria to receive intermediates that damage DNA, ribosomes, cell wall

Question 50

What are the acute symptoms of nitrofurantoin?

Answer 50

fever, chills, cough, infiltrates

Question 51

What are the chronic symptoms of nitrofurantoin?

Answer 51

Malaise, DOE, altered PFTs, pneumonitis, fibrosis

Question 52

What color might nitrofurantoin turn urine?

Answer 52

Brown

Question 53

What should you not use nitrofurantoin?

Answer 53

If patient has cholestatic jaundice or hepatic dysfunction w/ prior use > might lead to hepatic necrosis and death

Question 54

How is daptomycin administered?

Answer 54

Parenteral | It is a tidal lipopeptide 1x/day injection for G+ and MRSA skin infections

Question 55

What can't you use daptomycin for pneumonia?

Answer 55

It is inactivated by surfactant

Question 56

What is the mechanism of daptomycin?

Answer 56

Creates pore in membrane > K+ loss > depolarization > inhibits DNA, RNA and protein synthesis

Question 57

What are the side effects of daptomycin?

Answer 57

Increases creatine kinase

Question 58

How is daptomycin excreted?

Answer 58

By the kidneys unchanged

Question 59

What is quinidine used for?

Answer 59

IV for life-threatening Plasmodium falciparum

Question 60

What does rifampin target?

Answer 60

Penetrates tissues and biofilm to target most G+ and many G-; staph & MRSA; intracellular and extracellular organisms Penetrates lung cavities and abscesses Used only with other Rxs

Question 61

What is the mechanism of rifampin?

Answer 61

inhibits DNA-dependen RNA polymerase

Question 62

What is rifampin excreted by?

Answer 62

Through the enterohepatic circulation so through bile

Question 63

What happens if you give rifampin for more than 2 weeks?

Answer 63

Flu like symptoms

Question 64

What are the side effects of rifampin?

Answer 64

Rd/orange color to urine, feces, saliva, sweat and tears Rash, fever, nausea, vomiting Jaundice Hepatitis (rare if normal liver)

Question 65

What increases your chances of hepatitis when using rifampin?

Answer 65

Liver Disease Alcohol Increased Age