Rifamycins are used to treat tuberculosis, traveler's diarrhea, and irritable bowel syndrome. They also have other uses, such as preventing meningitis. Rifamycins work by stopping bacteria from making enzymes that are essential for their growth and survival. These medications come in different forms, including oral pills and injections. Examples include rifampin (Rifadin), rifaximin (Xifaxan), and rifabutin (Mycobutin).