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Antibiotic — Fluoroquinolone Pregnancy: Contraindicated — risk of arthropathy

Levofloxacin

Brand names: Tavanic

Adult dose

Dose: 250–500 mg
Route: Oral / IV
Frequency: Once or twice daily
Max: 1 g/day
Community-acquired pneumonia (severe): 500 mg BD for 7–14 days. UTI (complicated): 250 mg once daily for 7–10 days. IV for hospitalised patients unable to take oral. MHRA 2019: restrict use to serious infections only — risk of disabling, long-lasting side effects.

Paediatric dose

Route:
Seek specialist opinion — fluoroquinolones generally avoided in children due to risk of arthropathy; use under specialist guidance only

Dose adjustments

Renal

Reduce dose if eGFR <50: 250 mg daily (or 500 mg loading then 250 mg daily); if eGFR <20: 250 mg every 48 hours.

Hepatic

No specific dose adjustment required for hepatic impairment (primarily renally excreted).

Clinical pearls

  • MHRA 2019 safety restriction: fluoroquinolones should be reserved for serious, life-threatening infections when no suitable alternative — due to risk of disabling and potentially permanent musculoskeletal and neurological adverse effects
  • Stop immediately if tendinitis, tendon rupture, peripheral neuropathy, or CNS symptoms occur — and avoid further fluoroquinolones
  • Achilles tendon rupture risk increased in patients on corticosteroids — avoid combination if possible
  • Excellent tissue penetration and oral bioavailability — oral dose equivalent to IV in most infections

Contraindications

  • Previous fluoroquinolone-induced tendon disorder
  • Epilepsy or lowered seizure threshold
  • QT prolongation
  • Myasthenia gravis (may worsen)
  • Concomitant QT-prolonging drugs

Side effects

  • Tendinopathy/tendon rupture (especially Achilles — may occur weeks after stopping)
  • Peripheral neuropathy
  • CNS effects (seizures, psychosis, anxiety, insomnia)
  • QT prolongation
  • Dysglycaemia (hypo/hyperglycaemia)
  • Photosensitivity
  • C. difficile infection

Interactions

  • Antacids/iron/zinc (reduce absorption — give 2 hours apart)
  • Warfarin (potentiates anticoagulation)
  • NSAIDs (lowers seizure threshold)
  • QT-prolonging drugs (additive — avoid)
  • Antidiabetics (dysglycaemia)
  • Theophylline (increased seizure risk)

Monitoring

  • Signs of tendinopathy (especially Achilles)
  • Blood glucose (especially in diabetic patients)
  • ECG if QT risk factors
  • Signs of peripheral neuropathy

Reference: BNFc; BNF 90; MHRA Drug Safety Update 2019 (Fluoroquinolone Antibiotics); NICE NG138 (Pneumonia). Verify against your local formulary and the latest BNF before prescribing.

Related

Curated clinical cross-links plus same-class fallbacks.

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