Vancomycin is a potent antibiotic effective against a range of serious bacterial infections. It combats certain types of resistant bacteria that can cause severe illness.
Oral Vancomycin and Absorption
Oral vancomycin is poorly absorbed from the gastrointestinal tract into the bloodstream. After ingestion, only a minimal amount enters the systemic circulation. Most of the orally administered vancomycin remains within the digestive system, where it acts locally.
Unlike many other antibiotics, oral vancomycin’s primary action is confined to the gut lumen. This profile dictates its specific applications, as poor absorption ensures high concentrations are maintained directly where needed within the digestive tract.
Treating Gut Infections with Oral Vancomycin
Given its poor absorption, oral vancomycin is primarily used to treat infections confined to the gastrointestinal tract. Its most prominent application is in managing Clostridioides difficile infection (CDI). This bacterial infection causes inflammation of the colon, leading to symptoms like severe diarrhea and abdominal pain. Oral vancomycin is effective for CDI because it remains concentrated within the colon, directly targeting the Clostridioides difficile bacteria.
Its presence in the gut lumen allows it to directly inhibit these harmful bacteria. This local action minimizes systemic side effects, as the drug does not widely distribute throughout the rest of the body. Oral vancomycin therapy for CDI typically involves a specific dosing regimen, often for a period of 10 to 14 days, depending on the severity and recurrence of the infection. Its ability to achieve high concentrations in the gut makes it a preferred treatment for this specific type of bacterial colitis.
Vancomycin for Systemic Infections
For bacterial infections occurring outside the gastrointestinal tract, vancomycin cannot be administered orally. Instead, systemic infections require vancomycin to be given intravenously (IV). This method of administration ensures that the antibiotic directly enters the bloodstream and circulates throughout the body. Administering vancomycin intravenously allows the drug to reach the site of infection, whether it is in the bloodstream, bones, lungs, or other tissues.
Intravenous vancomycin is commonly employed to treat serious infections caused by Gram-positive bacteria, particularly Methicillin-resistant Staphylococcus aureus (MRSA). Examples include bloodstream infections (bacteremia), bone infections (osteomyelitis), or severe skin and soft tissue infections. The IV route ensures that effective concentrations of vancomycin are delivered to the infected tissues, allowing it to combat bacteria that are not confined to the digestive system.