FLUOROQUINOLONES

Question 1

What kind of antibiotics are fluoroquinolones?

Answer 1

synthetic, broad-spectrum antibiotics

Question 2

Fluoroquinolones are divided into two groups. What are the older fluoroquinolones?

Answer 2

ciprofloxacin [Cipro]
ofloxacin [Floxin]

Question 3

Fluoroquinolones are divided into two groups. What are the newer fluoroquinolones? What are they often referred to as?

Answer 3

(often referred to as the respiratory fluoroquinolones because of their activity against S. pneumoniae)
levofloxacin [Levaquin]
moxifloxacin [Avelox]
delafloxacin [Baxdela]

Question 4

What is the MOA of fluoroquinolones?

Answer 4

bactericidal through interference with enzymes required for the synthesis and repair of bacterial deoxyribonucleic acid (DNA)
extra info: inhibit bacterial topoisomerase II (DNA gyrase) and topoisomerase IV. Inhibition of DNA gyrase prevents the relaxation of positively supercoiled DNA that is required for normal transcription and replication

Question 5

What effect does the fluorine molecule have on fluoroquinolone activity?

Answer 5

Fluorine molecule added to create the fluoroquinolones provides increased potency against gram-negative organisms and broadens the spectrum to include gram-positive organisms as well.

Question 6

What are the two fluoroquinolones that have activity against P. Aeruginosa?

Answer 6

Only ciprofloxacin and levofloxacin

Question 7

Fluoroquinolones have notable activity against?

Answer 7

notable for their extensive gram-negative activity
Ex: E. Coli, Klebsiella, +more

Question 8

How is resistance mediated against fluoroquinolones?

Answer 8

Resistance is mediated by mutations in the quinolone-binding region of the target enzyme or by a change in the permeability of the organism. Overuse of these agents has already eroded the utility of this group of drugs.

Question 9

How well are fluoroquinolones absorbed PO?

Answer 9

All drugs in this class are well-absorbed after oral administration

Question 10

How are fluoroquinolones distributed?

Answer 10

All drugs in this class are widely distributed, with high tissue and urinary levels.
Tissue concentrations > than plasma concentrations

Question 11

Do fluoroquinolones readily cross BBB and placenta?

Answer 11

Minimal BBB crossing. All apear to cross to placenta.

Question 12

How much are fluoroquinolones metabolized?

Answer 12

Very minimal metabolism

Question 13

How are fluoroquinolones excreted?

Answer 13

Predominant route of elimination varies widely between fluoroquinolones.
Ofloxacin and levofloxacin have predominant renal excretion with minimal (less than 10%) metabolism

Question 14

At what CrCl level should fluoroquinolones be renally dosed?

Answer 14

For patients with CrCl of 50 mL/min or less, dosage adjustments are necessary for all fluoroquinolones, except for moxifloxacin

Question 15

What is the boxed warning for fluoroquinolones?

Answer 15

All fluoroquinolones have a boxed warning regarding the risk of tendon rupture and tendonitis. The risk is increased in older patients, patients taking corticosteroids, and patients immunosuppressed. An additional boxed warning has been issued to avoid all fluoroquinolones in patients with myasthenia gravis.

Question 16

What is the age recommendations for fluoroquinolones?

Answer 16

Fluoroquinolones are not recommended for children younger than 18 years.

Question 17

What are three possible adverse effects of fluoroquinolones?

Answer 17

C. Diff
Serious and occasionally fatal hypersensitivity reactions, including Stevens–Johnson syndrome and anaphylaxis
Phototoxicity has been observed with all fluoroquinolones

Question 18

Fluoroquinolones are first-line therapy in the treatment of?

Answer 18

traveler’s diarrhea and severe diarrhea not associated with antibiotic therapy.

Question 19

Which respiratory fluoroquinolones are used for community-acquired pneumonia?

Answer 19

levofloxacin and moxifloxacin