Vancomycin is an antibiotic used to treat a number of bacterial infections. It is recommended intravenously as a first-line treatment for complicated skin infections, bloodstream infections, endocarditis, bone and joint infections, and meningitis caused by methicillin-resistant S. aureus. Blood levels may be measured to determine the correct dose. Vancomycin is also recommended by mouth as a treatment for severe Clostridium difficile colitis. When taken by mouth it is very poorly absorbed.Common side effects include pain in the area of injection and allergic reactions. Occasionally problems with hearing, low blood pressure, or bone marrow suppression occur. Safety in pregnancy is not clear but there is no evidence of harm, and it is likely safe for use when breastfeeding. It is a type of the glycopeptide antibiotic and works by blocking the making of a cell wall.Vancomycin was first sold in 1954. It is on the World Health Organization's List of Essential Medicines, the most important medications needed in a basic health system. It is available as a generic medication. The wholesale cost of an intravenous dose is about 1.70 to 6.00 USD. In the United States the pills are very expensive. The intravenous solution may be taken by mouth for C. dif to reduce costs. Vancomycin is made by the soil bacterium Amycolatopsis orientalis.