FA fluoroquinolones

Question 1

1st generation?

Answer 1

1st generation: nalidixic acid (oral)

Question 2

2nd generation?

Answer 2

2nd generation: norfloxacin, ciprofloxacin, ofloxacin (oral), enoxacin (oral or IV)

Question 3

3rd generation?

Answer 3

3rd generation: levofloxacin (oral or IV)

Question 4

4th generation?

Answer 4

4th generation: moxifloxacin, gemifloxacin, gatifloxacin (oral)

Question 5

respiratory fluoroquinolones?

Answer 5

Levofloxacin, moxifloxacin, and gemifloxacin are respiratory fluoroquinolones.

Question 6

non-respiratory fluoroquinolones?

Answer 6

ciprofloxacin, enoxacin, norfloxacin, ofloxacin

Question 7

fluoroquinolones mechanism?

Answer 7

inhibition of prokaryotic topoisomerase II (DNA gyrase) and topoisomerase IV→ DNA supercoiling → formation of double-stranded breaks → inhibition of DNA replication and transcription (bactericidal effect)

Question 8

fluoroquinolones static or cidal?

Answer 8

cidal

Question 9

fluoroquinolones must not be taken with what?

Answer 9

antacids

Question 10

fluoroquinolones inhibits what 2 enzymes?

Answer 10

prokaryotic topoisomerase II (DNA gyrase) and topoisomerase IV

Question 11

fluoroquinolones cns penetration?

Answer 11

good

Question 12

fluoroquinolones route of ellimination?

Answer 12

Primarily renal (via glomerular filtration and tubular secretion)

Moxifloxacin undergoes biliary excretion.

Absorption is reduced when coadministered with polyvalent cations (e.g., magnesium, calcium, iron).

Question 13

Norfloxacin, ciprofloxacin, and ofloxacin indications?

Answer 13

Norfloxacin, ciprofloxacin, and ofloxacin:
a) Gram-negative rods causing urinary and gastrointestinal infections
b) Some gram-positive pathogens
c) Genitourinary infections caused by Neisseria gonorrhoeae, Chlamydia trachomatis, and/or Ureaplasma urealyticum
c) Ciprofloxacin: Pseudomonas aeruginosa (e.g., malignant otitis externa)

Question 14

ciprofloxacin special indication?

Answer 14

Ciprofloxacin: Pseudomonas aeruginosa (e.g., malignant otitis externa)

Question 15

Levofloxacin, moxifloxacin, and gemifloxacin indications?

Answer 15

Levofloxacin, moxifloxacin, and gemifloxacin:
a) Atypical bacteria (e.g., Legionella spp., Mycoplasma spp., Chlamydophila pneumoniae)
b) Also effective against anaerobes
c) Gemifloxacin is highly potent against penicillin-resistant pneumococci.
d) Moxifloxacin: 2nd-line treatment of tuberculosis in patients who cannot tolerate antitubercular drugs and in multidrug resistant tuberculosis

Question 16

fluoroquinolones adverse? dahuja cia

Answer 16

GI upset
Neurological symptoms
Mild headache
Dizziness
Mood changes
Peripheral neuropathy
Can lower seizure threshold (increased risk in patients taking NSAIDs and those with a previous history of epilepsy)
!!Hyperglycemia/hypoglycemia
!!QT prolongation
Photosensitivity
Skin rash
Superinfection (most commonly with gram-positive pathogens)
Potentially life-threatening exacerbations in patients with myasthenia gravis
In children: potential damage to growing cartilage → reversible arthropathy

!!!!!!Muscle ache, leg cramps, tendinitis, tendon rupture, especially of the Achilles tendon (the risk of tendon rupture is higher for individuals over 60 years of age and for individuals on steroid therapy)

Question 17

fluoroquinolones special considerations?

Answer 17

Special considerations: increased risk for drug interactions as ciprofloxacin inhibits cytochrome P450

Question 18

fluoroquinolones contraindications? dahuja

Answer 18

!!!Children and teenagers < 18 years of age
Patients > 60 years of age and those taking cortisol
!!!!!Pregnant women
!!!!Breastfeeding women
Epilepsy, stroke, CNS lesions/inflammation
QT prolongation
Myasthenia gravis
Cautious use in patients with:
Renal failure
Hepatic failure
Antacid use [61]
Known aortic aneurysm or increased risk of aneurysms (e.g., Marfan syndrome, Ehlers-Danlos syndrome, advanced age, peripheral atherosclerotic disease, hypertension)

Question 19

fluoroquinolones resistance?

Answer 19

Mechanism of resistance
Chromosome-encoded mutation in DNA gyrase and topoisomerase IV enzymes
Altered cell wall permeability
Plasmid-encoded mutations in efflux pump proteins