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Antibiotic — Severe CAP / Legionella Pregnancy: Avoid — potential cartilage toxicity; use amoxicillin + clarithromycin for CAP in pregnancy

Levofloxacin

Brand names: Tavanic

Adult dose

Dose: 500 mg once daily (oral/IV)
Route: Oral / IV
Frequency: Once daily (5–10 days CAP; 10–14 days Legionella)
Max: 500 mg/day (CAP); 750 mg/day (severe CAP/HAP)
Respiratory fluoroquinolone with excellent coverage including Legionella pneumophila, Streptococcus pneumoniae, Mycoplasma, and Chlamydophila. Used for severe CAP (CRB-65 ≥3) or when Legionella suspected/confirmed. Oral bioavailability ~99% — IV to oral switch when tolerating.

Paediatric dose

Dose: Seek specialist opinion mg/kg
Route: Oral / IV
Frequency: Once daily
Max: Not first-line in children — cartilage toxicity risk
BNFc: avoid routine use in children under 18 years — fluoroquinolone cartilage toxicity; use only under specialist guidance for specific indications (e.g. cystic fibrosis — Pseudomonas)

Dose adjustments

Renal

Significant dose reduction required: eGFR 20–49 — 250 mg OD; eGFR 10–19 — 125 mg OD

Hepatic

No dose adjustment in mild-moderate hepatic impairment

Paediatric weight-based calculator

BNFc: avoid routine use in children under 18 years — fluoroquinolone cartilage toxicity; use only under specialist guidance for specific indications (e.g. cystic fibrosis — Pseudomonas)

Clinical pearls

  • MHRA 2019 and 2023: restrict fluoroquinolones — only when no suitable alternative; counsel on tendon, cardiac, CNS, and aortic risks; document reason for use
  • Legionella pneumonia: levofloxacin 500 mg BD × 10–14 days is first-line (azithromycin is an alternative) — notifiable disease; contact PHE
  • Oral bioavailability essentially 100% — no clinical advantage to IV in patients who can swallow; switch oral as soon as patient tolerating
  • HAP/VAP: levofloxacin 750 mg OD is an option in non-pseudomonal HAP when beta-lactam allergic or resistant — always check local antibiogram
  • Tendon rupture risk highest in patients >60 years, on corticosteroids, or with renal/organ transplant history — monitor closely; stop if tendon pain

Contraindications

  • Fluoroquinolone hypersensitivity or tendon disorders with quinolones
  • QT prolongation
  • Pregnancy (cartilage toxicity)
  • Children <18 years (routine)

Side effects

  • Tendinopathy/tendon rupture (Achilles — most common)
  • QT prolongation
  • C. difficile
  • CNS effects (seizures, confusion)
  • Peripheral neuropathy
  • Photosensitivity
  • Aortic aneurysm (MHRA 2023)

Interactions

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

Monitoring

  • Symptom response at 48–72 hours
  • Renal function (dose adjustment)
  • Tendon symptoms
  • ECG (QTc) in high-risk patients

Reference: BNFc; BNF 90; BNFc; NICE NG138; MHRA Drug Safety Update (2019, 2023); BTS CAP Guidelines; PHE Legionella guidance. Verify against your local formulary and the latest BNF before prescribing.

Related

Curated clinical cross-links plus same-class fallbacks.

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