linezolid

Action

Selectively binds to bacterial 23S ribosomal RNA of 50S subunit, preventing formation of essential component of bacterial protein synthesis. Bacteriostatic or bactericidal against gram-positive and some gram-negative bacteria.

Availability

Injection: 2 mg/ml

Powder for oral suspension: 100 mg/5 ml

Tablets: 400 mg, 600 mg

Indications and dosages

➣ Vancomycin-resistant Enterococcus faecium infections

Adults and children ages 12 and older: 600 mg P.O. or I.V. infusion q 12 hours for 14 to 28 days

Children from birth to age 11: 10 mg/kg I.V. q 8 hours for 14 to 28 days

➣ Nosocomial pneumonia; community-acquired pneumonia; complicated skin and skin-structure infections

Adults and children ages 12 and older: 600 mg P.O. or I.V. infusion q 12 hours for 10 to 14 days

Children from birth to age 11: 10 mg/kg P.O. or I.V. q 8 hours for 10 to 14 days

➣ Uncomplicated skin and soft-tissue infections

Adults: 400 mg P.O. q 12 hours for 10 to 14 days

Adolescents: 600 mg P.O. or I.V. q 12 hours for 10 to 14 days

Children ages 5 to 11: 10 mg/kg P.O. or I.V. q 12 hours for 10 to 14 days

Children younger than age 5: 10 mg/kg P.O. or I.V. q 8 hours for 10 to 14 days

Contraindications

• Hypersensitivity to drug or its components

Precautions

Use cautiously in:

• hepatic dysfunction, hypertension, hyperthyroidism, pheochromocytoma, bone marrow depression, pseudomembranous colitis

• phenylketonuria (oral suspension only)

• pregnant or breastfeeding patients.

Administration

• Give oral drug with or without food.

• For I.V. injection, use single-use, ready-to-use infusion bag. Check for particulate matter before giving. Infuse over 30 minutes to 2 hours.

• For I.V. infusion, mix with dextrose 5% in water, normal saline solution, or lactated Ringer's injection.

• Flush I.V. line before and after administering, to avoid incompatibilities.

Adverse reactions

CNS: anxiety, confusion, difficulty speaking, dizziness, hallucinations, lethargy, paresthesia, light-headedness, fatigue, drowsiness, headache, seizures

GI: nausea, vomiting, diarrhea, gastritis, anorexia, dry mouth, pseudomembranous colitis

Hematologic: thrombocytopenia

Skin: rash, photosensitivity, diaphoresis

Other: fever, fungal infections

Interactions

Drug-drug. Antiplatelet drugs (such as aspirin, dipyridamole, nonsteroidal anti-inflammatory drugs): increased bleeding risk

MAO inhibitors, pseudoephedrine: increased risk of hypertension and associated adverse effects

Serotonergics: serotonin syndrome

Drug-diagnostic tests. Prothrombin time: altered

Drug-food. Tyramine-containing foods and beverages (such as beer; Chianti and certain other red wines; aged cheese; bananas; aged, cured, or spoiled meats; salted herring and other dried fish; avocado; bean curd; red plums; soy sauce; spinach; tofu, tomatoes; yeast): hypertension

Patient monitoring

• Monitor neurologic status. Institute safety measures as needed to prevent injury.

• Check I.V. site for infiltration.

☞ Watch for bleeding and signs and symptoms of other adverse reactions (especially pseudomembranous colitis).

• Monitor CBC, coagulation studies, and culture and sensitivity tests.

Patient teaching

• Tell patient he may take with or without food, but should avoid foods containing tyramine.

☞ Tell patient to promptly report bleeding or severe diarrhea.

• Instruct patient to minimize adverse GI effects by eating small, frequent servings of healthy food.

• Caution patient to avoid driving and other hazardous activities until he knows how drug affects concentration and alertness.

• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs, tests, and foods mentioned above.