Rifampicin, also known as rifampin, is an antibiotic used to treat several types of bacterial infections, including tuberculosis, mycobacterium avium complex, leprosy, and Legionnaire's disease. It is almost always used together with other antibiotics, except when given to prevent Haemophilus influenzae type b and meningococcal disease in people who have been exposed to those bacteria. Before treating a person for a long period of time, measurements of liver enzymes and blood counts are recommended. Rifampicin may be given either by mouth or intravenously.