What is the recommended dosage and treatment duration for Zyvox (linezolid) in adult patients?

Zyvox (Linezolid) Dosing and Duration for Adult Patients

For adult patients, linezolid should be dosed at 600 mg every 12 hours (either oral or intravenous), with treatment duration ranging from 10-28 days depending on the specific infection type. 1

Standard Adult Dosing

• 600 mg every 12 hours (oral or IV) is the recommended dose for most serious gram-positive infections in adults 1
• No dose adjustment is needed when switching from IV to oral administration, as linezolid has 100% oral bioavailability 2
• IV infusions should be administered over 30-120 minutes 1

Duration by Infection Type

Skin and Soft Tissue Infections

• Complicated SSTI: 10-14 days of treatment 1
• Uncomplicated SSTI: 10-14 days at 400 mg every 12 hours (adults) or 600 mg every 12 hours (adolescents) 1

Pneumonia

• Community-acquired pneumonia: 14-28 days 1
• Nosocomial pneumonia: 14-28 days 1
• Both types use 600 mg every 12 hours 1

Bacteremia and Vancomycin-Resistant Enterococcus

• VRE infections with concurrent bacteremia: 14-28 days 1
• Dose remains 600 mg every 12 hours 1

Osteomyelitis

• Minimum 6 weeks of treatment required 3
• Some experts recommend an additional 1-3 months for chronic infection or inadequate debridement 3
• Standard dose of 600 mg twice daily applies 4

CNS Infections

• Meningitis: 2 weeks at 600 mg every 12 hours 4
• Brain abscess, subdural empyema, spinal epidural abscess: 4-6 weeks at 600 mg every 12 hours 4

Important Clinical Considerations

Monitoring Requirements

• Weekly complete blood counts should be obtained for patients receiving linezolid for more than 14 days due to risk of reversible thrombocytopenia 5
• Discontinue if myelosuppression develops 5
• Thrombocytopenia occurs in approximately 2.4% of patients, particularly with treatment ≥2 weeks 5

Drug Interactions and Dietary Restrictions

• Linezolid is a weak, reversible monoamine oxidase inhibitor 5, 2
• Avoid tyramine-rich foods during treatment 5
• Use with caution when coadministering adrenergic or serotonergic agents 5, 2
• Coadministration with pseudoephedrine or phenylpropanolamine can increase blood pressure 2

Surgical Considerations

• For osteomyelitis, surgical debridement is the mainstay of therapy and should be performed whenever feasible 3
• For CNS infections, neurosurgical evaluation for drainage is recommended 4

Combination Therapy

• Some experts recommend adding rifampin 600 mg daily or 300-450 mg twice daily for osteomyelitis 3
• For patients with concurrent bacteremia, rifampin should only be added after bacteremia clearance 3
• Linezolid is not routinely recommended as adjunctive therapy for invasive MRSA disease, though may be considered in severe sepsis or necrotizing pneumonia 4

Common Pitfalls

• The most frequent adverse events are diarrhea, headache, nausea, and vomiting, which are typically mild to moderate 5, 6
• Duration-dependent thrombocytopenia is the primary hematologic concern 5, 7
• No dosage adjustment needed for hepatic or renal impairment in most cases, though caution is warranted in severe renal insufficiency requiring hemodialysis 2
• Linezolid should not be used in series IV connections, and certain drugs are physically incompatible during Y-site administration (amphotericin B, diazepam, phenytoin) 1