Linezolid Oral Dosing Regimen
The standard oral dosing regimen for linezolid in adults is 600 mg twice daily (every 12 hours), while for children the dosing varies by age: children ≥12 years receive 600 mg twice daily and children <12 years receive 10 mg/kg every 8 hours. 1, 2
Adult Dosing
- 600 mg orally every 12 hours is the standard adult dose for most indications including complicated skin and skin structure infections, pneumonia, and infections caused by resistant gram-positive organisms 2
- Duration of therapy is typically 10-14 days for uncomplicated skin and skin structure infections, but may be longer for more serious infections 2
- Linezolid can be administered without regard to meals, though high-fat food may slightly delay absorption (time to peak concentration increases from 1.5 to 2.2 hours) without affecting total drug exposure 3
- Linezolid is 100% bioavailable when given orally, making oral dosing equivalent to intravenous dosing without need for dose adjustment 3, 4
Pediatric Dosing
- For children ≥12 years: 600 mg orally twice daily (every 12 hours), same as adult dosing 1, 2
- For children <12 years: 10 mg/kg orally every 8 hours (30 mg/kg/day in 3 divided doses), not to exceed 600 mg per dose 5, 1
- Higher weight-based dosing in younger children is necessary due to their higher clearance of linezolid compared to adults 4
Special Populations
- No dosage adjustment is required for elderly patients, patients with mild to moderate hepatic impairment, or mild to severe renal impairment 4
- Women may have slightly higher plasma concentrations than men, but this difference does not warrant dosage adjustment 4
- Caution should be used in patients with severe renal insufficiency as metabolite levels may be significantly higher 4
Monitoring
- Complete blood counts should be monitored weekly in patients receiving linezolid for more than two weeks due to potential hematologic effects 2, 6
- Thrombocytopenia has been reported in approximately 2% of patients treated with linezolid, particularly with treatment durations exceeding 14 days 6
Common Side Effects
- Most common adverse events include diarrhea, nausea, and headache in adults; these are typically mild to moderate in intensity and limited in duration 6
- In children, common side effects include diarrhea, loose stools, and vomiting 6
Drug Interactions
- Linezolid is a mild, reversible inhibitor of monoamine oxidase (MAO) enzymes 4, 6
- Foods containing high concentrations of tyramine should be avoided during treatment 6
- Use with caution in patients taking adrenergic or serotonergic agents or in those with uncontrolled hypertension 6
Linezolid's excellent oral bioavailability makes it particularly valuable for treating serious gram-positive infections in both inpatient and outpatient settings, allowing for seamless transition from intravenous to oral therapy without compromising efficacy 4, 7.