What is the recommended dosing for linezolid (Zyvox)?

Linezolid Dosing Recommendations

The recommended dosage for linezolid (Zyvox) is 600 mg intravenously or orally every 12 hours for adults and adolescents 12 years and older for most infections. 1

Adult Dosing

Standard Dosing

• 600 mg IV/PO every 12 hours for:
  • Complicated skin and skin structure infections (10-14 days)
  • Community-acquired pneumonia (10-14 days)
  • Nosocomial pneumonia (10-14 days)
  • Vancomycin-resistant Enterococcus faecium infections (14-28 days)
  • MRSA infections (10-14 days) 1, 2

Exception

• 400 mg PO every 12 hours for uncomplicated skin and skin structure infections (10-14 days) 1

Pediatric Dosing

Children under 12 years

• 10 mg/kg IV/PO every 8 hours for most infections 1
• For uncomplicated skin infections:
  • <5 years: 10 mg/kg oral every 8 hours
  • 5-11 years: 10 mg/kg oral every 12 hours 1

Neonates

• Neonates <7 days (especially preterm <34 weeks gestation): 10 mg/kg IV/PO every 12 hours initially
• All neonates should receive 10 mg/kg every 8 hours by 7 days of life 1

Duration of Treatment

• Complicated skin and skin structure infections: 10-14 days
• Pneumonia (community-acquired or nosocomial): 10-14 days
• Vancomycin-resistant Enterococcus faecium infections: 14-28 days
• Uncomplicated skin and skin structure infections: 10-14 days 1
• Enterococcal infections: Duration dependent on site of infection and clinical response 2

Special Considerations

Administration

• No dose adjustment necessary when switching from IV to oral administration 1
• IV administration should be over 30-120 minutes 1
• Food slightly decreases the rate but not the extent of absorption 3

Monitoring

• Complete blood counts should be monitored weekly in patients receiving linezolid for more than 14 days 4
• Treatment should be discontinued if there is evidence of myelosuppression 4

Adverse Effects

• Most common adverse events: diarrhea (9.8%), thrombocytopenia (7.4%), decreased hemoglobin/hematocrit (4.1%), and cutaneous reactions (4.0%) 5
• Thrombocytopenia risk increases with treatment duration >2 weeks 4

Drug Interactions

• Avoid coadministration with adrenergic or serotonergic agents due to weak monoamine oxidase inhibition 3, 4
• Foods containing high concentrations of tyramine should be avoided 4
• No dose adjustment required for mild to moderate renal or hepatic impairment 3
• Use with caution in patients with severe renal insufficiency 3

Special Populations

• Women may have higher plasma concentrations than men, but dose adjustment is not warranted 3
• Children have higher clearance of linezolid compared to adults, hence the higher mg/kg dosing 3

Clinical Efficacy

• High clinical cure rates (91.5%) and microbiological success rates (85.8%) in patients with multidrug-resistant gram-positive infections 5
• Effective for treating vancomycin-resistant enterococci and methicillin-resistant staphylococci 6

Pitfalls to Avoid

• Do not use in series connections for IV administration 1
• Avoid adding other drugs to linezolid IV solution due to physical incompatibilities 1
• Do not continue therapy beyond recommended duration without close monitoring due to increased risk of myelosuppression 4
• Consider therapeutic drug monitoring in special populations (children, renal insufficiency patients) to optimize dosing and minimize toxicity 7