Glycopeptide antibiotics

Glycopeptide antibiotics are a type of antibiotic that inhibits bacterial cell wall formation by inhibiting peptidoglycan synthesis. They are used for treating multi-resistant Staphylococcus aureus (MRSA) infections and enterococcal infections, which are resistant to beta-lactams and other antibiotics. They are also used in cases where there is an allergy to beta-lactams.

What are glycopeptide antibiotics used for?

Glycopeptide antibiotics are usually reserved for the treatment of serious infections caused by MRSA, Streptococcus, or Enterococcus bacteria which are resistant to beta-lactams and other antibiotics, such as

• Clostridium difficile-associated diarrhea
• Endocarditis
• Enterocolitis
• Pneumonia acquired during a hospital stay or that develops while using a ventilator
• Severe skin and skin structure infections
• Other serious infections that are not susceptible to other antibiotics.

What are the differences between glycopeptide antibiotics?

Vancomycin was the first glycopeptide antibiotic approved. The other three glycopeptides available in the U.S. (dalbavancin, oritavancin, and telavancin) are structurally related to vancomycin and were developed to improve on vancomycin’s duration of action and tolerability. However, reports suggest that one glycopeptide, telavancin, is no more effective than vancomycin and has more adverse effects.

None are absorbed orally, although vancomycin is effective when given orally for the treatment of Clostridium difficile-associated diarrhea because this infection is localized in the gut. Vancomycin and telavancin are given once daily, whereas dalbavancin is given once weekly or as a single infusion, and oritavancin as a single infusion.

The need for monitoring in patients receiving vancomycin is controversial, and the manufacturer does not consider it necessary. There is not considered any value in monitoring the other glycopeptides.

Are glycopeptide antibiotics safe?

Vancomycin and telavancin may affect kidney function; the risk is greatest in those older than 65 years. Monitoring of kidney function during and immediately following treatment may be required. Studies have reported that telavancin causes more renal adverse effects than vancomycin.

Telavancin can interfere with some clotting tests and can cause prolongation of the QT interval (the measurement on an ECG that represents electrical depolarization and repolarization of the ventricles).

Glycopeptides may be ototoxic (toxic to the auditory nerve, cochlear, or vestibular system of the ear). This may cause transient or permanent hearing loss. The risk is highest in people given large intravenous doses, with pre-existing hearing loss, or receiving another ototoxic agent, such as gentamicin.

Rarely, "Red Man Syndrome" has been associated with vancomycin IV and dalbavancin. Symptoms include flushing of the upper body, shortness of breath, a skin rash, itching, pain, muscle spasms and low blood pressure. Most reactions resolve within 20 minutes; however, some may persist for several hours.

Rarely, some people may develop a super-infection due to overgrowth of a naturally occurring bacterium called Clostridium difficile, following use of any antibiotic, including glycopeptide antibiotics. Symptoms include severe diarrhea.

For a complete list of severe side effects, please refer to the individual drug monographs.

What are the side effects of glycopeptide antibiotics?

Side effects that have been reported with glycopeptide antibiotics include:

• Abdominal pain
• Back pain
• Diarrhea
• Edema
• Flatulence
• Foamy urine
• A headache
• Infusion reactions
• Itchy skin
• Low potassium levels
• Nausea
• Rash
• Taste disturbance
• Urinary tract infection
• Vomiting.

For a complete list of side effects, please refer to the individual drug monographs.