Levofloxacin
Levaquin
Respiratory fluoroquinolone
DNA gyrase/topoisomerase IV inhibitor; broader gram-positive/atypical ('respiratory') coverage than cipro.
Indications
- •Community-acquired pneumonia, sinusitis, UTI, atypicals
Dosing
| Context | Adult | Pediatric |
|---|---|---|
| Typical | 500–750 mg IV/PO daily | — |
Pharmacokinetics
Half-life ~6–8 h → once-daily. Renally cleared.
Side effects
- !Same fluoroquinolone class effects: QT, tendinopathy, aortic risk, dysglycemia, CNS, myasthenia exacerbation
- !C. difficile
Contraindications
- ×Long QT
- ×Myasthenia gravis
- ×Tendon disorder history
Clinical pearls
- ★'Respiratory' fluoroquinolone — same Black-Box class harms as ciprofloxacin; watch QT + glucose swings.
Other drugs in Antibiotics
- Cefazolin
β-lactam — inhibits bacterial cell wall PBPs.
- Vancomycin
Inhibits cell wall synthesis (binds D-Ala-D-Ala). Active against MRSA + gram-positives.
- Clindamycin
Binds 50S ribosomal subunit, blocks peptide-bond formation. Bacteriostatic against most organisms; bactericidal against susceptible streptococci. Excellent activity against anaerobes and gram-positive cocci including community-acquired MRSA.
- Gentamicin
Binds 30S ribosomal subunit, causes misreading of mRNA → defective bacterial protein synthesis. Bactericidal, concentration-dependent killing. Synergy with cell-wall agents (β-lactams, vancomycin) for gram-positive endocarditis.
- Cefuroxime
β-lactam — inhibits cell-wall synthesis (PBP binding). 2nd-gen: gram-positive + expanded gram-negative.
- Cefepime
β-lactam cell-wall inhibitor. Broad gram-negative (incl. Pseudomonas) + gram-positive coverage.
- Cefotetan
β-lactam; adds anaerobic (B. fragilis) coverage → colorectal/gynecologic prophylaxis.
- Cefotaxime
β-lactam cell-wall inhibitor. Broad gram-negative + CNS penetration.
Browse all classes: /reference/drugs
Suggested reading
- •Miller's Anesthesia, 9e
- •FDA package insert
