What You Should Know About Vancomycin

Vancomycin is an antibiotic of last resort usually used to treat drug-resistant infections. Vancomycin was first isolated from Bornean soil samples more than 50 years ago. Initially, few clinicians used vancomycin, instead preferring other antibiotics which were considered more effective (vancomycin takes longer to act than penicillins) and less toxic.

However, beginning in the early 1980s, physicians and other health-care professionals started to express renewed interest in this drug. This renewed interest was due both to vancomycin's ability to fight methicillin-resistant Staphylococcus aureus (MRSA) and the ability to treat pseudomembranous colitis. Pseudomembranous colitis is a nasty infection of the colon (diarrhea) which takes hold after treatment with other antibiotics that kill normal bowel flora. 

Mechanism of Action

Vancomycin is a tricyclic glycopeptide. It binds to bacterial cell walls and alters cell membrane permeability. It also interferes with bacterial RNA synthesis.

When fighting most gram-positive organisms like staphylococci and streptococci, vancomycin's actions are bacteriocidal. In other words, vancomycin works to directly kill the gram-positive bacteria. However, when fighting enterococci, another type of gram-positive organism, vancomycin's actions are bacteriostatic, and it works to inhibit bacteria reproduction.

Coverage

Vancomycin is used to fight several types of bacterial pathogens, many of which are resistant to other types of antibiotics including:

• Severe staphylococcal infections in people who are allergic to penicillin (affects skin and bloodstream)
• Methicillin-resistant Staphylococcus aureus (MRSA) (affects skin and bloodstream)
• Methicillin-resistant staphylococcus epidermidis (affects skin, implanted medical devices, bloodstream)
• Drug-resistant streptococcus pneumoniae (affects lungs, ears, meninges [brain lining])
• Severe enterococcal infections in people who are allergic to penicillin (affects skin, heart valves, bloodstream)
• Severe enterococcal infections that are resistant to penicillin
• Viridans streptococci (affects bloodstream and heart valves)
• Multi-drug resistant corynebacterium jeikeium (affects bloodstream and heart valves)
• Clostridium difficile (affects GI tract)

Diseases Treated

Vancomycin is used to treat several forms of serious infection including:

• Pneumonia
• Bone, skin, and soft-tissue infections
• Peritonitis (inflammation of the peritonium, within the abdominal wall)
• Endocarditis (heart infection)
• Enterocolitis and pseudomembranous colitis (bowel infections)
• Prophylaxis when undergoing dental, biliary, GI, respiratory and genitourinary infections
• Brain abscess (off-label use)
• Perioperative infections (off-label use)
• Meningitis (off-label use)

Administration and Dosage

Because vancomycin is poorly absorbed by the gastrointestinal tract, it is usually administered as an injection. However, when used to treat enterocolitis and pseudomembranous colitis, both infections of the gastrointestinal tract, patients take oral vancomycin.

Vancomycin is usually administered in an inpatient (hospital) setting. Inpatient pharmacists are usually called on to calculate dosages. Furthermore, because vancomycin is excreted by the kidneys, the dosing of this drug is more complicated in people with renal failure.

Adverse Effects

Serious detrimental side effects attributable to vancomycin are rare, and vancomycin's most common adverse effect is a limited hypersensitivity or allergic reaction, as well as fever, nausea, rash, and tinnitus. In rare yet serious cases, vancomycin can be nephrotoxic and damage the kidneys, especially when administered with aminoglycosides, another type of antibiotic.

Moreover, when administered with aminoglycosides or high-dose intravenous erythromycin, also another type of antibiotic, vancomycin can damage hearing (ototoxicity). Finally, vancomycin can cause hyperemia or red-man syndrome, a type of flushing; such flushing can be mitigated if the patient is first given antihistamines.

A Word From Verywell

Vancomycin resistance poses a growing concern among clinicians, researchers and epidemiologists alike. Because vancomycin is one of our last lines of defense against dangerous and drug-resistant disease, the prospect that it will no longer work to combat infection is undeniably frightful and leaves us with few other options.

Specifically, strains of vancomycin-resistant enterococci have cropped up in hospitals worldwide. Because vancomycin is usually administered in hospitals, skilled-nursing facilities, nursing homes and so forth, it's imperative that healthcare professionals take steps to limit vancomycin resistance such as curbing overprescription and limiting the spread of vancomycin resistance among patients through proper patient isolation and hygiene practices.