Fluoroquinolones

Question 1

(T/F) - Fluoroquinolones have a broad-spectrum activity against gram (-) and (+) organisms

Answer 1

FALSE - Gram (-), (+), and atypical organisms

Question 2

(T/F) - Fluoroquinolones display an excellent oral F

Answer 2

TRUE

Question 3

(T/F) - Fluoroquinolones have a high incidence of adverse effects

Answer 3

FALSE - low incidence

Question 4

What is the MOA of fluoroquinolones?

Answer 4

Inhibits DNA gyrase (bacterial topoisomerase) leading to DNA strand breaks and rapid bactericidal activity

Question 5

What are the mechanisms of resistance for fluoroquinolones?

Answer 5

• Mutation of target site (DNA gyrase)
• Decreased permeability of outer cell wall membrane of gram (-) bacteria
• Production of efflux proteins that actively trasnport fluoroquinolones out of bacteria

Question 6

What are the drugs that fall under the fluoroquinolone class?

Answer 6

• Ciprofloxacin
• Moxifloxacin
• Levofloxacin
• Gemifloxacin
• Delafloxacin

Question 7

Which fluoroquinolones are also known as respiratory quinolones?

Answer 7

• Gemifloxacin
• Moxifloxacin
• Levofloxacin

Question 8

Ciprofloxacin has a good spectrum over which bacteria?

Answer 8

• Enteric GNRs
• Pseudomonas
• H. influenzae

Question 9

Respiratory quinolones have a good spectrum over which bacteria?

Answer 9

• H. influenzae
• Enteric GNRs
• Pseudomonas
• S. pneumoniae
• Atypicals

Question 10

Only one respiratory quinolone is active against pseudomonas, which one is it?

Answer 10

Levofloxacin

Question 11

What adverse events could occur with fluoroquinolones?

Answer 11

• CNS
• CV
• Musculoskeletal
• Dermatologic

Question 12

What type of CNS adverse events could occur?

Answer 12

• Dizziness
• Peripheral neuropathy
• Hallucinations
• Confusion
• Insomnia

Question 13

What type of CV adverse events could occur?

Answer 13

QT prolongation

Question 14

What type of musculoskeletal adverse events could occur?

Answer 14

• Arthralgias (uncommon)

- Achilles tendon rupture (black boxed warning)

Question 15

Who is more likely to gain Achilles tendon rupture as an adverse event w/ fluoroquinolones?

Answer 15

• Elderly
• Renal dysfunction pts
• Pts on corticosteroids

Question 16

What type of dermatologic adverse event could occur?

Answer 16

Photosensitivity

Question 17

What is a contraindication of flouroquinolones?

Answer 17

Pregnant and children

Question 18

What is the dose of ciprofloxacin in pseudomonas?

Answer 18

• 400 mg IV q 8 h
  OR
• 750 mg PO q 12 h

Question 19

What is the dose of levofloxacin in pseudomonas?

Answer 19

• 750 mg PO or IV q 24 h

Question 20

What is the percentage of bioavailability with fluoroquinolones?

Answer 20

80-100%

Question 21

(T/F) - ALL fluoroquinolones dose given PO are the same dose as IV

Answer 21

FALSE - all except ciprofloxacin (po = 1.25 x IV)

Question 22

(T/F) - ALL fluoroquinolones chelate cations which decrease the oral F of fluoroquinolones

Answer 22

TRUE

Question 23

Which cations chelate with fluoroquinolones?

Answer 23

• Mg
• Ca
• Fe
• Milk
• MVIs
• antacids

Question 24

What should be done if a patient is taking cations and flouroquinolones?

Answer 24

Separate by at least 2 hrs

Question 25

Fluoroquinolones are problematic with what else?

Answer 25

Tube feeds

Question 26

How are fluoroquinolones cleared?

Answer 26

Renally

Question 27

Which fluoroquinolone is not renally cleared?

Answer 27

Moxifloxacin

Question 28

Moxifloxacin is not best to be used in which indication?

Answer 28

UTIs

Question 29

The FDA has stated to use fluoroquinolones if risks outweigh benefits for which indications?

Answer 29

- Sinusitis - Bronchitis - Uncomplicated UTIs

Question 30

Delafloxacin can be administered how?

Answer 30

- IV | - PO

Question 31

Delafloxacin has a good spectrum in which bacteria?

Answer 31

- Gram (+) including MRSA | - Gram (-) including pseudomonas

Question 32

What is delafloxacin FDA approved of?

Answer 32

Skin/soft tissue infections

Question 33

Should delafloxacin be used whenever for any infections?

Answer 33

No, it shouldn't be used unnecessarily to avoid development of resistance

Question 34

What is the usual dose of delafloxacin given PO?

Answer 34

450 mg PO q 12 h

Question 35

What is the usual dose of delafloxacin given IV?

Answer 35

300 mg IV q 12 h