Linezolide Kalceks (Linezolid)

Linezolid is an antibacterial agent used to manage serious Gram‑positive infections.

• MRSA infection: effective bacterial clearance in skin, soft‑tissue and bloodstream infections.
• VRE infection: eradicates vancomycin‑resistant Enterococcus in complicated intra‑abdominal and urinary tract infections.
• Community‑acquired pneumonia caused by susceptible Gram‑positive organisms: shortens clinical recovery and reduces complications.

• Linezolid inhibits bacterial protein synthesis by binding to the 50S ribosomal subunit, preventing formation of the initiation complex. This action blocks translation of essential proteins, leading to bacteriostatic activity against susceptible Gram‑positive organisms, including resistant strains such as MRSA and VRE.

Linezolid may cause a range of adverse reactions, most of which are dose‑independent.

Common Side Effects

• Nausea: mild to moderate gastrointestinal discomfort.
• Diarrhea: loose stools, often self‑limiting.
• Headache: transient cranial pain.
• Metallic taste: altered taste perception.
• Myelosuppression: mild reduction in blood cell counts.
• Rash: non‑specific skin eruption.

Serious or Rare Side Effects

• Thrombocytopenia: significant drop in platelet count requiring monitoring.
• Peripheral neuropathy: sensory changes that may be irreversible.
• Lactic acidosis: metabolic disturbance with high morbidity.
• Serotonin syndrome: risk when combined with serotonergic agents.
• Hepatotoxicity: elevated liver enzymes indicating liver stress.
• Vision changes: optic neuropathy leading to visual impairment.

Before initiating Linezolid therapy, consider patient‑specific factors and monitoring requirements.

• Renal impairment: adjust monitoring as the drug is primarily excreted unchanged.
• Hepatic dysfunction: observe liver function tests periodically.
• Hematologic disorders: baseline CBC recommended; watch for thrombocytopenia.
• Concomitant serotonergic drugs: avoid due to risk of serotonin syndrome.
• Pregnancy and lactation: use only if benefits outweigh potential risks, as safety data are limited.
• Store at ambient temperature: keep in original container, protect from light and moisture.

Linezolid interacts with several drug classes; awareness helps prevent adverse events.

Major Interactions (Avoid)

• Selective serotonin reuptake inhibitors (SSRIs) and other serotonergic agents: risk of serotonin syndrome.
• Monoamine oxidase inhibitors (MAOIs): may precipitate hypertensive crisis.

Moderate Interactions (Monitor Closely)

• Rifampicin: may reduce linezolid plasma concentrations.
• Warfarin: potential increase in anticoagulant effect, monitor INR.
• Ethanol: may enhance central nervous system depression.
• NSAIDs: increased risk of bleeding when combined with thrombocytopenia.
• Digoxin: possible alteration of serum levels, monitor therapeutic range.