Synthetic antibacterial agent of the oxazolidinone class.
Active against Gram‑positive aerobic bacteria, some Gram‑positive anaerobes, and certain Gram‑negative bacteria.
Mechanism of action: Binds to 23S rRNA of the 50S ribosomal subunit, preventing formation of the functional 70S initiation complex → inhibition of bacterial protein synthesis.
Activity:
- Bacteriostatic against enterococci and staphylococci.
- Bactericidal against most streptococci strains.

Route: Oral (with or without food) or IV infusion (30–120 minutes).
Switching: No dose adjustment needed when switching IV ↔ oral.
Pediatric (birth–11 years):
- Neonates <7 days: 10 mg/kg every 12 h; may increase to every 8 h if response is suboptimal.
- By 7 days of life: 10 mg/kg every 8 h.
Children 5–11 years: 10 mg/kg orally every 12 h.
Adults & adolescents (≥12 years): 600 mg orally/IV every 12 h.
Treatment duration:
- Nosocomial pneumonia: 10–14 days
- Community‑acquired pneumonia: 10–14 days
- Complicated skin/soft tissue infections: 14–28 days
- Uncomplicated skin infections: 10–14 days
Special populations:
- Mild–moderate hepatic impairment: No adjustment.
- Severe hepatic impairment: Not evaluated.

Drug: Linezolid is a reversible, nonselective MAO inhibitor.
- Risk of serotonin syndrome with SSRIs, TCAs, triptans, meperidine, buspirone.
- Enhanced pressor response with sympathomimetics, vasopressors, dopaminergic agents.
Food: Avoid large amounts of tyramine‑rich foods/beverages.

Hypersensitivity to Linezolid or formulation components.
Concurrent or recent (within 2 weeks) use of MAO‑A/B inhibitors (e.g., phenelzine, isocarboxazid).
Patients with uncontrolled hypertension, pheochromocytoma, thyrotoxicosis, carcinoid syndrome, or those receiving sympathomimetics, vasopressors, dopaminergic agents, serotonergic drugs.

Common: Diarrhea, headache, nausea.
Others: Oral/vaginal candidiasis, hypertension, dyspepsia, abdominal pain, pruritus, tongue discoloration.

Weekly CBC monitoring recommended, especially >2 weeks therapy or in patients with myelosuppression.
Ophthalmic evaluation if visual changes occur.
Not approved for catheter‑related bloodstream infections.
Risk of C. difficile‑associated diarrhea (can occur up to 2 months post‑therapy).
Monitor blood pressure in at‑risk patients.
Evaluate promptly if recurrent nausea, vomiting, acidosis, or hypoglycemia occurs.