Levofloxacin
Mechanism :
Levofloxacin inhibits bacterial type II topoisomerases, topoisomerase IV and DNA gyrase. Levofloxacin, like other fluoroquinolones, inhibits the A subunits of DNA gyrase, two subunits encoded by the gyrA gene. This results in strand breakage on a bacterial chromosome, supercoiling, and resealing; DNA replication and transcription is inhibited.
Indication :
- Inhalational anthrax
- Plague
- Acute bacterial rhinosinusitis (off-label)
- Community-acquired pneumonia, bacterial (off label)
- Community-acquired pneumonia, atypical (off label)
- Multidrug resistant tuberculosis
Contraindications :
Hypersensitivity to drug/class/component
Prolonged QT interval, Hypokalemia, Myasthenia gravis, Colitis history.
Caution if proarrhythmic condition, renal impairment, seizure disorder or seizure threshold lowered, CNS disorder, dehydration, diabetes mellitus.
Caution if kidney, heart or lung transplant.
Dosing :
Use in children above 6 months of age.
Inhalational anthrax, plague:
<50 kg:
16-20 mg/kg/day orally in two divided doses. Max: 750 mg/day.
>50 kg:
500 mg orally once a day. Max: 750 mg/day.
Duration:
2 months for inhalational anthrax, 10-14 days for plague, 10 days for acute bacterial sinusitis, community acquired bacterial pneumonia, community acquired atypical pneumonia.
Adverse Effect :
Common Reactions: Nausea, headache, diarrhea, insomnia, constipation, dizziness, abdominal pain, vomiting, dyspepsia, tendinitis.
Serious Reactions: Anaphylaxis, hypersensitivity reaction, toxic psychosis, phototoxicity, Clostridium difficile associated diarrhea, depression, superinfection, Raised ICP, seizures, suicidal ideation, QT prolongation, skin reaction, severe torsades de pointes, vasculitis, pneumonitis, hypersensitivity, serum sickness, nephrotoxicity, hepatotoxicity, myelosuppression, blood dyscrasias, peripheral neuropathy, tendon rupture, arthralgia/myalgia, arthropathy (animal studies), myasthenia gravis, exacerbation.
Interaction :
Contraindicated:
Amiodarone, BCG live intravesical, Cisapride, Disopyramide, Dofetilide, Dronedarone, Ibutilide, Pimozide, Procainamide, Quinidine (Antiarrhythmic), Sotalol, Thioridazine, Ziprasidone.
Avoid/Use Alternative:
Aminolevulinic acid topical, Arsenic Trioxide, Artemether/lumefantrine, Asenapine, Bedaquiline, Ciprofloxacin, Clarithromycin, Crizotinib, Degarelix, Dolasetron, Ephedra, Ephedrine, Erythromycin, Goserelin, Haloperidol, Histrelin, Iloperidone, Leuprolide, Lopinavir/Ritonavir, Methadone, Mifepristone, Nilotinib, Paliperidone, Pasireotide, Pentamidine, Quinine, Ranolazine, Saquinavir, Sunitinib, Telavancin, Tetrabenazine, Toremifene, Triptorelin, Typhoid vaccine live, Vandetanib.
Renal Dose :
Dose in Renal Impairment GFR (mL/min)
| 20-50 | Initial dose 250–500 mg then reduce dose by 50% |
| 10-20 | Initial dose 250–500 mg then 125 mg 12–24 hourly |
| <10 | Initial dose 250–500 mg then 125 mg 24–48 hourly |
Dose in Patients undergoing Renal Replacement Therapies
| CAPD | Not dialysed. Dose as in GFR<10 mL/min |
| HD | Not dialysed. Dose as in GFR<10 mL/min |
| HDF/High flux | Not dialysed. Dose as in GFR<10 mL/min |
| CAV/VVHD | Not dialysed. Loading dose: 500 mg then 250 mg every 24 hours |
Hepatic Dose :
No dose adjustments are recommended.