Benfloxin

Approved Indications (Oral/IV):

• Community-acquired pneumonia (CAP), including cases due to multidrug-resistant Streptococcus pneumoniae
• Hospital-acquired pneumonia (HAP)
• Acute bacterial sinusitis
• Acute bacterial exacerbation of chronic bronchitis (AECB)
• Uncomplicated urinary tract infections (UTIs)
• Complicated UTIs and acute pyelonephritis
• Chronic bacterial prostatitis
• Complicated and uncomplicated skin and skin structure infections (SSSIs)
• Post-exposure prophylaxis for inhalational anthrax
• Treatment of plague (including pneumonic and septicemic)

Approved Indications (Ophthalmic):

• Bacterial conjunctivitis

Approved Indications (Otic):

• Acute otitis externa

Clinically Accepted Off-Label Uses:

• Traveler’s diarrhea (alternative therapy)
• Multidrug-resistant tuberculosis (as part of combination therapy)

General Notes:

• Oral and IV formulations are bioequivalent; switch between them without dose adjustment.
• Dose and duration vary based on infection type, severity, and renal function.

Adults (Oral/IV):

Pediatric Use (Anthrax/Plague only):

• 6 months to <50 kg: 8 mg/kg orally/IV every 12 hours (max 250 mg/dose)
• ≥50 kg: 250 mg every 12 hours
• Duration: 10–14 days

Renal Impairment (CrCl <50 mL/min):

Hepatic Impairment:

• No dose adjustment required

Ophthalmic (Bacterial Conjunctivitis):

• Days 1–2: 1–2 drops in affected eye(s) every 2 hours while awake (up to 8 times/day)
• Days 3–7: 1–2 drops every 4 hours while awake (up to 4 times/day)

Otic (Acute Otitis Externa):

• 4 drops into affected ear once daily for 7 days

Levofloxacin hemihydrate is a bactericidal fluoroquinolone that acts by inhibiting two essential bacterial enzymes: DNA gyrase (topoisomerase II) and topoisomerase IV. These enzymes are vital for bacterial DNA replication, transcription, repair, and recombination. Inhibition of these enzymes prevents the uncoiling and supercoiling processes necessary for DNA function, leading to DNA strand breaks, interruption of cell division, and ultimately bacterial cell death. Its activity spans both Gram-positive and Gram-negative pathogens.

• Absorption: Rapid and nearly complete (oral bioavailability ~99%)
• Peak Plasma Concentration: 1–2 hours post-oral dose
• Distribution: Widely distributed in tissues (lungs, urinary tract, prostate, skin)
• Volume of distribution: ~89–112 L
• Protein binding: 24–38%
• Metabolism: Minimal hepatic metabolism
• Elimination Half-life: ~6–8 hours
• Excretion:
• Renal: ≥85% excreted unchanged in urine
• Fecal: Minor elimination

• Pregnancy: Category C
  Animal studies have shown adverse fetal effects (cartilage damage). Use only if potential benefit outweighs the risk.
• Lactation:
  Levofloxacin is excreted into breast milk. Due to the risk of serious musculoskeletal effects in infants, breastfeeding is not recommended during treatment.

• Primary Class: Antibiotic
• Subclass: Fluoroquinolone (Third generation)

• Hypersensitivity to levofloxacin, other quinolones, or formulation components
• History of tendon rupture or tendinopathy associated with fluoroquinolones
• Myasthenia gravis (may exacerbate muscle weakness)
• Co-administration with tizanidine is contraindicated

• Tendon Rupture: Risk increased in patients ≥60 years, on corticosteroids, or post-transplant
• Peripheral Neuropathy: May be irreversible—discontinue if symptoms occur
• CNS Effects: Seizures, tremors, hallucinations, or psychosis may occur
• QT Prolongation: Caution in patients with known QT prolongation or concurrent QT-prolonging agents
• Glycemic Disturbances: Monitor blood glucose in diabetic patients
• Phototoxicity: Avoid sunlight/UV exposure during and shortly after treatment
• Aortic Aneurysm/Dissection: Use with caution in elderly and those with vascular disease
• C. difficile Infection: Ranges from mild diarrhea to fatal colitis

Common (>1%):

• Gastrointestinal: Nausea, diarrhea, vomiting, abdominal pain
• Neurologic: Headache, dizziness, insomnia
• Musculoskeletal: Arthralgia, tendonitis
• Dermatologic: Rash, photosensitivity

Serious/Rare:

• Tendon rupture (Achilles tendon)
• Peripheral neuropathy
• QT prolongation, torsades de pointes
• Hypoglycemia or hyperglycemia
• CNS toxicity (hallucinations, seizures)
• Hepatotoxicity
• Stevens-Johnson syndrome
• Clostridioides difficile-associated diarrhea

• Antacids, Iron, Zinc, Sucralfate: Reduce absorption—space administration by ≥2 hours
• Warfarin: May enhance anticoagulant effect—monitor INR
• NSAIDs: Potential for increased CNS stimulation and seizure risk
• Hypoglycemic Agents (Insulin, Sulfonylureas): Monitor for hypo/hyperglycemia
• QT-Prolonging Drugs (e.g., amiodarone, sotalol): Risk of additive arrhythmia
• CYP450: Levofloxacin is not a major substrate, inhibitor, or inducer of CYP enzymes

• FDA Black Box Warning (Reaffirmed 2018):
  Levofloxacin and other fluoroquinolones are associated with disabling and potentially irreversible side effects including tendon rupture, peripheral neuropathy, and CNS effects. Reserve use for infections where no alternatives are available.
• WHO/NICE Guidelines:
  Recommend fluoroquinolones only when safer antibiotics are not suitable. Now considered second-line therapy for many respiratory and urinary infections.

• Tablets/Oral Solution:
  Store at 20°C to 25°C (68°F to 77°F); excursions permitted between 15°C and 30°C. Protect from moisture and light.
• IV Solution:
  Store at 15°C to 30°C. Do not freeze. Use diluted solution within recommended timeframes.
• Ophthalmic/Otic Drops:
  Store at 2°C to 25°C (36°F to 77°F). Do not freeze. Discard 28 days after opening.
• Handling Instructions:
  Shake oral liquids before use. Use aseptic technique for IV preparation. Follow expiration and discard after reconstitution if applicable.