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Antibiotic — Fluoroquinolone Pregnancy: Avoid — potential cartilage toxicity in fetal bone development; use alternative antibiotic

Levofloxacin

Brand names: Tavanic

Adult dose

Dose: 500 mg once daily (sinusitis: 5–10 days)
Route: Oral / IV
Frequency: Once daily
Max: 500 mg/day (ENT); 750 mg/day (severe)
Reserved for severe or complicated acute sinusitis when first-line antibiotics (amoxicillin, co-amoxiclav) have failed or when penicillin allergy contraindicated alternatives. Also used for malignant otitis externa (combined with ciprofloxacin or alone). Not first-line — MHRA restriction on fluoroquinolone use.

Paediatric dose

Dose: Seek specialist opinion mg/kg
Route: Oral / IV
Frequency: Once daily
Max: Not established as first-line in children <18 years
BNFc: avoid in children under 18 except for specific indications (e.g. malignant otitis externa in exceptional circumstances) — risk of cartilage toxicity

Dose adjustments

Renal

Significant dose adjustment required — reduce dose if eGFR <50 mL/min/1.73m²

Hepatic

No dose adjustment in mild-moderate hepatic impairment

Paediatric weight-based calculator

BNFc: avoid in children under 18 except for specific indications (e.g. malignant otitis externa in exceptional circumstances) — risk of cartilage toxicity

Clinical pearls

  • MHRA 2019: restrict fluoroquinolone use — avoid for mild/moderate ENT infections; reserve for when no alternative; counsel on tendon, CNS, and cardiac risks
  • MHRA 2023: fluoroquinolones associated with aortic aneurysm — avoid in patients with aortic disease or risk factors
  • Malignant (necrotising) otitis externa: Pseudomonas aeruginosa infection of skull base in diabetics/immunocompromised — oral ciprofloxacin 750 mg BD or levofloxacin 500 mg OD × 6–8 weeks; monitor ESR/CRP
  • Tendon rupture risk: highest in patients >60, on corticosteroids, or with renal/transplant history — stop immediately if tendon pain
  • Fluoroquinolone resistance increasing in UK — check local antibiogram before prescribing
  • Good penetration into sinus mucosa — bioavailability ~99% (oral = IV)

Contraindications

  • Fluoroquinolone hypersensitivity or previous tendon disorder with quinolone
  • Pregnancy (avoid)
  • Children <18 years (routine)
  • G6PD deficiency (relative)

Side effects

  • Tendinopathy/tendon rupture (most serious — Achilles)
  • QT prolongation
  • CNS effects (seizures, confusion — especially elderly)
  • GI disturbance
  • Photosensitivity
  • C. difficile
  • Aortic aneurysm (rare — MHRA warning)

Interactions

  • QT-prolonging drugs — additive QTc prolongation
  • NSAIDs — increased seizure risk
  • Antacids, iron, calcium — reduce absorption (separate by 2h)
  • Warfarin — increased INR

Monitoring

  • Symptom response
  • Tendon pain (stop immediately if occurs)
  • QTc (at-risk patients)
  • Renal function

Reference: BNFc; BNF 90; BNFc; MHRA Drug Safety Update (2019 and 2023) Fluoroquinolones; NICE NG78 (Sinusitis 2017). Verify against your local formulary and the latest BNF before prescribing.

Related

Curated clinical cross-links plus same-class fallbacks.

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