Ofloxacin

 

1. Generic & Brand Names

• Generic: Ofloxacin

• Brands: Floxin® (global), Ocuflox® (ophthalmic), Tarivid® (EU/Asia)

• Formulations:

  • Tablets (200mg, 300mg, 400mg)

  • IV infusion (200mg/50mL, 400mg/100mL)

  • Ophthalmic/Otic solutions (not for systemic use)

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2. Drug Class & Mechanism

• Class: Fluoroquinolone antibiotic (2nd gen)

• Mechanism: Inhibits DNA gyrase/topoisomerase IV → bactericidal

• Spectrum:

  • Gram-negative: E. coli, K. pneumoniae, P. aeruginosa

  • Gram-positive: S. pneumoniae (limited), S. aureus (MSSA)

  • Atypicals: Chlamydia, Mycoplasma

  • Anaerobic: B. fragilis (moderate)

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3. FDA-Approved Uses

Infection Type	Key Pathogens	Status
Lower Respiratory Tract	S. pneumoniae, H. influenzae	Alternative*
Acute Bacterial COPD Exacerbations	H. influenzae, M. catarrhalis	Restricted*
Uncomplicated UTI	E. coli, K. pneumoniae	Last-line
Complicated UTI/Pyelonephritis	P. aeruginosa	Reserved
Prostatitis	Enterobacteriaceae	Alternative

⚠️ FDA RESTRICTIONS (2016/2023):

• Avoid for sinusitis, bronchitis, uncomplicated UTIs unless no alternatives exist.

• Reserve for:

  • Pyelonephritis with suspected Pseudomonas

  • Multi-drug resistant (MDR) infections

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4. Dosing Regimens

Infection Type	Adult Dose	Duration
Lower Respiratory	400 mg PO/IV q12h	7-14 days
Uncomplicated UTI	200 mg PO q12h	3-7 days
Complicated UTI/Pyelonephritis	200-400 mg PO/IV q12h	10-21 days
Prostatitis	300 mg PO q12h	6 weeks
Renal Adjustment:

• CrCl 20-50 mL/min: ↓ dose 50%

• CrCl <20 mL/min: Avoid systemic use

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5. Black Box Warnings (FDA)

1. Tendon Rupture:

   • Achilles > shoulder/hand tendons

   • Risk ↑ in: >60 yrs, steroid use, kidney transplant

2. Peripheral Neuropathy:

   • Irreversible nerve damage (pain/tingling/weakness)

3. CNS Effects:

   • Insomnia, psychosis, suicidal ideation

4. Exacerbates Myasthenia Gravis:

   • May cause respiratory failure

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6. Side Effects

Common (≥10%)	Serious (Discontinue Immediately)
Nausea/vomiting	Tendon rupture
Headache	QT prolongation → Torsades
Diarrhea	Aortic dissection
Photosensitivity	Hypersensitivity reactions
Dizziness	C. difficile colitis

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7. Critical Drug Interactions

Medication	Risk
NSAIDs	↑ Seizure risk
Corticosteroids	↑ Tendon rupture risk
Antidiabetics	↑ Hypoglycemia (glipizide/glyburide)
Theophylline	↑ Levels → toxicity (monitor serum)
Antacids/Ca²⁺/Fe²⁺	↓ Absorption (separate by 4h)

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8. Resistance & Stewardship

• UTI Resistance Concerns:

  35% E. coli resistant in US outpatient UTIs (IDSA 2023)

• Avoid For:

  • Strep throat, viral infections, mild skin infections

  • Pediatric patients (cartilage damage risk)

• First-Line Alternatives:

  • Uncomplicated UTI: Nitrofurantoin, Fosfomycin

  • Respiratory: Amoxicillin-clavulanate, Doxycycline

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9. IV-to-PO Transition

• Bioavailability: 98% oral → switch to PO as soon as clinically feasible

• IV Administration:

  • Infuse 400 mg over ≥60 min (rapid infusion → hypotension)

  • Avoid IV for >10 days (↑ thrombophlebitis risk)

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10. Storage & Handling

• Tablets: 15-30°C (59-86°F); protect from light/moisture

• Oral Suspension: Not commercially available (compounded)

• IV Solution: Discard unused portions; refrigerate intact vials

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Clinical Practice Guidelines

✅ Appropriate Use:

• MDR Pseudomonas UTIs/prostatitis

• Atypical pneumonia in penicillin-allergic patients

• Institutional protocols with confirmed susceptibility
  ❌ Avoid:

• Uncomplicated infections

• Patients with tendon/CNS disorders

⚠️ Mandatory Counseling:

• "Stop drug for tendon pain/mood changes."

• "Avoid sunlight/sunlamps (use SPF 50+)."

• "Take 2h before/4h after antacids/vitamins."

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Ofloxacin vs. Other Fluoroquinolones

Parameter	Ofloxacin	Ciprofloxacin	Levofloxacin
Pseudomonas Coverage	++	+++	++
Respiratory Penetration	Moderate	Low	High
QTc Prolongation Risk	High	Moderate	High
Urinary Concentration	High	High	Moderate

📊 Efficacy Data:

• Complicated UTI cure rate: 82% vs. 85% for ciprofloxacin (J Antimicrob Chemother)

• Resistance in respiratory isolates: S. pneumoniae (15-25%), H. influenzae (5-10%)

Prescribing Status: Restricted in US/EU; requires justification of "no suitable alternatives."

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💡 Key Insight: Reserve for confirmed MDR infections in consultation with infectious disease specialists. Always perform culture/susceptibility testing before use.