Glycopeptide Antibiotics: Notes and MCQ for NEETPG, GPAT, BPharm, BSc Nursing Exams
Classification
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Natural Glycopeptides:
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Vancomycin
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Teicoplanin
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Semisynthetic/Lipoglycopeptides:
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Telavancin
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Dalbavancin
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Oritavancin
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Pharmacology
| Parameter | Details |
|---|---|
| Mechanism of Action | Inhibits bacterial cell wall synthesis by binding to D-Ala-D-Ala terminus |
| Bactericidal/Static | Bactericidal against Gram-positive bacteria |
| Spectrum | Narrow spectrum – active mainly against Gram-positive cocci (e.g., MRSA) |
| Resistance | Due to modification of D-Ala-D-Ala to D-Ala-D-Lac (e.g., VRE) |
Uses
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MRSA infections
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C. difficile colitis (oral vancomycin)
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Enterococcal infections (sensitive strains)
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Skin and soft tissue infections
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Pneumonia and endocarditis (esp. caused by resistant Gram-positive bacteria)
Adverse Drug Reactions (ADRs)
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Nephrotoxicity
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Ototoxicity
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Red man syndrome (rapid IV infusion → histamine release)
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Hypersensitivity reactions
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Phlebitis at injection site
Drug-Drug Interactions
| Interacting Drug | Effect |
|---|---|
| Aminoglycosides | ↑ Risk of nephrotoxicity and ototoxicity |
| Loop diuretics | ↑ Risk of ototoxicity |
| Neuromuscular blockers | Additive effect (caution with anesthesia) |
| Contrast media (IV) | ↑ Nephrotoxicity (monitor renal function closely) |
Chart: Pharmacology Parameters
| Drug | Uses | ADRs | Interactions |
|---|---|---|---|
| Vancomycin | MRSA, C. diff, endocarditis | Nephrotoxicity, ototoxicity | Aminoglycosides, loop diuretics |
| Teicoplanin | Gram-positive infections | Mild nephrotoxicity | Less interaction than vancomycin |
| Telavancin | Skin infections, HAP/VAP | Taste disturbance, foamy urine, nephrotoxicity | QT prolonging drugs |
| Dalbavancin | Acute bacterial skin infections | Nausea, headache | Minimal interactions |
| Oritavancin | Skin infections | Diarrhea, limb pain | Artificially prolongs aPTT (lab artifact) |
Chart: Pharmacokinetic Parameters
| Drug | Route | Half-life | Excretion | Dosing Frequency |
|---|---|---|---|---|
| Vancomycin | IV, oral | 6–10 hrs | Renal | Multiple daily doses |
| Teicoplanin | IV, IM | 30–100 hrs | Renal | Once daily or less |
| Telavancin | IV | ~8 hrs | Renal | Once daily |
| Dalbavancin | IV | ~170–210 hrs | Renal | Once weekly (or less) |
| Oritavancin | IV | ~245 hrs | Hepatic/renal | Single-dose regimen |
MCQs on Glycopeptide Antibiotics
1. What is the mechanism of action of glycopeptide antibiotics?
A) Inhibit protein synthesis
B) Inhibit DNA replication
C) Inhibit cell wall synthesis
D) Inhibit folate synthesis
→ Answer: C) Inhibit cell wall synthesis
2. Which of the following is used orally for Clostridium difficile infection?
A) Telavancin
B) Vancomycin
C) Oritavancin
D) Dalbavancin
→ Answer: B) Vancomycin
3. Red man syndrome is associated with which drug?
A) Teicoplanin
B) Vancomycin
C) Oritavancin
D) Ciprofloxacin
→ Answer: B) Vancomycin
4. Which of the following has the longest half-life?
A) Vancomycin
B) Telavancin
C) Dalbavancin
D) Teicoplanin
→ Answer: C) Dalbavancin
5. Which drug may falsely elevate aPTT due to lab interference?
A) Vancomycin
B) Teicoplanin
C) Oritavancin
D) Dalbavancin
→ Answer: C) Oritavancin