Pharm CNS infections

Question 1

What is the exception to giving abx IV for bacterial meningitis?

Answer 1

Rifampin

Question 2

Why would you add dexamethasone to tx of bacterial meningitis?

Answer 2

to control CNS inflammation and limit neurological deficits

Question 3

If a pt >50 yo has a beta lactam allergy, what should you tx the pt with for community acquired bacterial meningitis?

Answer 3

Vanc + Moxifloxacin + TMP-SMX

Question 4

What can be used to replace Vanc if the pt has a beta lactam allergy?

Answer 4

Linezolid

Question 5

What is the down side to adding dexamethasone to tx of bacterial meningitis?

What can we do to assist coverage?

Answer 5

may impair CNS entry of some abx (eg vanc)

add oral Rifampin to assist Vanc coverage

Question 6

What carbapenems are used or not used for meningitis and why?

Answer 6

imipenem is not used bc the sz risk is too high

meropenem is used bc it has the lowest sz risk

Question 7

What drug drug interaction do you need to be aware of when rx’ing most penicillins for meningitis?

Answer 7

probenecid - gout drug - inhibits tubular transport

doses should be reduced for pt, or pt with renal disease

Question 8

How is Nafcillin excreted?

Answer 8

via liver into bile

Question 9

No dosing adjustment are required for what two drugs if renal disease is present and you are tx’ing meningitis with penicillins?

Answer 9

nafcillin and oxacillin

Question 10

What two cephalosporins cover Pseudomonas?

Answer 10

3rd gen ceftazidime

4th gen cefepime

Question 11

What cephalosporin does not require dosing adjustments if the pt is on probenecid or has renal dz?

Answer 11

ceftriaxone

Question 12

What drug has the broadest spectrum of activity of any beta-lactam abx and is good for ESBL producing g- bacteria?

Answer 12

meropenem

Question 13

You should decrease drug dose of meropenem if the pt is also taking…

Answer 13

probenecid

Question 14

How do carbapenems interact with valproic acid?

Answer 14

decrease plasma levels, should consider alternative tx

Question 15

What is the only beta-lactam with NO gram positive bacteria coverage?

Answer 15

aztreonam

Question 16

aztreonam is only active against…

Answer 16

aerobic gram negative bacteria

Question 17

Is aztreonam sensitive to probenecid? Do you ever have to change dosage?

Answer 17

No interaction with probenecid

decrease drug dose for pt with impaired renal function

Question 18

What could be a croos-allergy risk with aztreonam?

Answer 18

ceftazidime

Question 19

Vanc covers most gram positive bacteria including MRSA, but does not cover

Answer 19

Listeria

Question 20

decrease Vanc dose if the pt has…

Answer 20

renal dz

Question 21

How does Red man syndrome occur as an AE of Vanc?

Answer 21

high IV infusion rate

d/t histamine release

pre-medicate with antihistamine

Question 22

What is the only way to administer polymixin abx?

What are examples of polymixins?

Answer 22

intrathecal or intraventricular

Polymixin B or Colistin (Polymixin E)

Question 23

How does chloramphenicol work as an abx?

Answer 23

binds 50S subunit, inhibiting protein synthesis

inhibits peptidyl transferase to prevent the addition of new aa to the polypeptide

Question 24

Who is chloramphenicol indicated to use in?

Answer 24

serious beta lactam abx allergy

Question 25

What is an AE of chloramphenicol in premature infants? Why does this happen?

Answer 25

gray baby syndrome - cyanosis, weakness, resp depression poor metabolism d/t lack of glucuronidation enzyme: UDP glucuronosyltransferase

Question 26

What are the top three AE of Chloramphenicol?

Answer 26

anemia aplastic anemia gray baby syndrome

Question 27

What is the MOA of Linezolid?

Answer 27

blocks 50S subunit from joinging up with 30S subunit, no complex formation, inhibiting protein synthesis by blocking initiation complex formation

Question 28

What are three AE of Linezolid?

Answer 28

bone marrow suppression risk for severe HTN, inhibition of MOA serotonin syndrome

Question 29

What is a drug interaction of Linezolid?

Answer 29

MOA contraindicated with MOAIs

Question 30

What is the MOA of TMP-SMX?

Answer 30

bactericidal when used together inhibit folate

Question 31

What g negatives does bactrim not cover?

Answer 31

N. meningitidis and Pseudomonas

Question 32

What CYP enzymes go with bactrim?

Answer 32

Inhibitors of CYP2C8 (TMP) and CYP2C9 (SMX)

Question 33

You should lower bactrim dose in pt with...

Answer 33

renal disease

Question 34

What AEs go with TMP-SMX?

Answer 34

hypersensitivity rxn, hemolytic anemia, crystalluria with SMX megaloblastic anemia with TMP both - Steven Johnsons Prego - avoid in last month (kernicterus)

Question 35

MOA of Fluoroquinolones? target in g + and g-??

Answer 35

DNA synthesis inhibitors Topoisomerase IV in g+ DNA gyrase in g-

Question 36

What fluoroquinolone covers Pseudomonas?

Answer 36

Cipro

Question 37

What fluoroquinolone covers strep, staph, and listeria?

Answer 37

moxifloxicin

Question 38

What is the exception to most fluoroquinolones excreted by the kidney?

Answer 38

moxi excreted by liver

Question 39

What are the major AEs of fluoroquinolones?

Answer 39

tendon rupture, QT prolongation cartilage damage

Question 40

Cipro inhibits CYP1A2 and should be cautioned with

Answer 40

caffeine and warfarin

Question 41

What is the least likely fluoroquinolone to induce QT prolongation?

Answer 41

cipro

Question 42

What drug can be used as prophylaxis for individuals exposed to meningitis caused by H influ and N meningitidis?

Answer 42

Rifampin

Question 43

What is MOA of Rifampin?

Answer 43

binds to DNA dependent RNA polymerase to prevent RNA synthesis