Vancomycin

Drug Overview

Vancomycin is a glycopeptide antibiotic primarily used to treat severe infections caused by certain Gram-positive bacteria. It exerts its effect by interfering with bacterial cell wall synthesis and is often used as a last-resort treatment, especially in patients with resistance to other antibiotics such as penicillin or cephalosporins.

Its clinical applications cover various life-threatening infections, including sepsis and endocarditis caused by methicillin-resistant Staphylococcus aureus (MRSA), as well as Enterobacteriaceae infections. Due to its unique metabolic pathway, it must be administered intravenously, with strict monitoring of drug levels to prevent toxicity.

Brand Names and Generic Name

The generic name of this drug is Vancomycin. Common brand names include:

• Vancocin
• Lyphocin
• Vancoled

Generic formulations and different preparations may have other brand names; verify the medication ingredients before use.

Drug Classification

Vancomycin is classified as a "glycopeptide antibiotic," belonging to the slow-acting bactericidal agents. Its mechanism involves binding to bacterial cell wall precursors, inhibiting cell wall synthesis, and thereby killing bacteria. This class of drugs is typically used for treating multi-drug resistant bacterial infections.

Indications

Main indications include:
1. Severe infections caused by methicillin-resistant Staphylococcus aureus (MRSA)
2. Enterococcal infections, such as urinary tract infections or endocarditis
3. Skin and soft tissue infections, such as necrotizing fasciitis
4. Prophylactic use before certain surgeries

This medication is usually used in hospitalized patients and should be administered under a physician’s guidance. Do not adjust dosage or administration method independently.

Common Side Effects

Mild Side Effects:

• Redness and pain at the injection site (phlebitis)
• "Red man syndrome": facial flushing, skin warmth (related to rapid infusion)

These reactions typically improve after reducing the infusion rate.

Serious Side Effects:

• Nephrotoxicity: may lead to abnormal kidney function or renal failure
• Ototoxicity: tinnitus or hearing loss (associated with high doses or rapid infusion)
• Clostridioides difficile infection (CDI): disruption of gut flora

If these symptoms occur, notify healthcare personnel immediately.

Warnings and Precautions

Contraindications:

• Allergy to vancomycin or its excipients
• Severe renal impairment requiring dose adjustment

Pregnancy and Breastfeeding:

• FDA pregnancy category B, but use should be evaluated by a physician considering potential risks
• May be secreted into breast milk; breastfeeding women should weigh benefits and risks before use

Drug Interactions

Concurrent use with the following drugs may increase the risk of adverse effects:

• Aminoglycosides (e.g., gentamicin): increased risk of nephrotoxicity
• Diuretics (e.g., furosemide): may exacerbate ototoxicity
• Oral hypoglycemic agents: changes in gut flora may affect efficacy

Always inform your healthcare provider of all medications you are taking before starting vancomycin.

Dosage and Administration

This medication must be administered via slow intravenous injection or infusion; oral or self-injection is not permitted. The common adult dose is 10-15 mg/kg every 6 to 12 hours, adjusted based on:

• Patient’s body weight
• Renal function
• Severity of infection

The duration of therapy depends on the type of infection, typically ranging from 14 to 28 days.

Missed Dose Management

If a scheduled dose is missed:

• If more than 4 hours have passed since the missed dose, administer it immediately
• If close to the next dose, skip the missed dose

Do not double the dose to make up for missed doses to avoid toxicity.

Overdose Management

Overdose may cause abrupt kidney function decline, hearing loss, or neurological abnormalities. Immediate actions include:

• Discontinue the drug
• Undergo hemodialysis to remove the drug
• Monitor renal function and hearing

If overdose is suspected, seek medical attention immediately.

 

Frequently Asked Questions

Why is it necessary to control the infusion rate during intravenous administration of vancomycin?

Rapid infusion of vancomycin can trigger "Red Man Syndrome," characterized by facial flushing and skin warmth. Healthcare providers usually limit the infusion time to 1 to 2 hours to reduce this risk. In special cases (e.g., severe infection), the physician may adjust the speed and monitor the patient’s response.

What are the differences in indications between oral vancomycin and intravenous use?

Oral vancomycin is mainly used for severe intestinal infections caused by Clostridioides difficile (e.g., pseudomembranous colitis), while intravenous formulations are used for systemic infections caused by resistant bacteria. Their absorption and site of action differ; they are not interchangeable without a physician’s prescription.

What interactions should be considered when combined with other antibiotics?

Combining vancomycin with aminoglycosides may increase the risk of nephrotoxicity, requiring regular kidney function monitoring. When used with fluoroquinolones like ciprofloxacin, pharmacokinetic interactions may affect efficacy, necessitating dosage or timing adjustments by the physician.

How should dosage be adjusted in patients with liver or kidney dysfunction?

Vancomycin blood levels are mainly affected by renal function; patients with severe renal failure require significantly extended dosing intervals. Liver dysfunction usually has less impact on pharmacokinetics, but if there is combined liver and kidney impairment, blood level monitoring is necessary to prevent accumulation and toxicity.

Are there dietary or activity restrictions during medication?

It is recommended to avoid dehydration during treatment, as hypovolemia may increase nephrotoxicity risk. There are no specific dietary restrictions, but if medications affecting gut flora (e.g., antacids) are used concurrently, consult your healthcare provider about timing to ensure proper absorption.