nitrofuran /-fyo̅o̅″ran/ , one of a group of synthetic antimicrobials used to treat infections caused by protozoa or by certain gram-positive or gram-negative bacteria. The precise mechanism by which nitrofurans exert their antimicrobial effects is not known, but several bacterial and protozoal enzyme systems are inhibited. Two agents commonly prescribed are furazolidone and nitrofurantoin. Furazolidone is used to treat bacterial and protozoal diarrhea and enteritis. Nitrofurantoin is used to treat urinary tract infections caused by Escherichia coli and other enteric pathogens of the urinary tract. Systemic administration of nitrofurans is associated with many side effects, the most common being nausea and diarrhea. Serious side effects include polyneuropathies and several hypersensitivity reactions, including pneumonitis and blood dyscrasias. Nitrofurans can cause hemolytic anemia in patients with glucose-6-phosphate dehydrogenase deficiency. Lastly, they cause a harmless brown discoloration of the urine.
