Fluconazole is an antifungal medication that is given either by mouth or intravenously. It is used to treat a variety of fungal infections, especially Candida infections of the vagina (yeast infections), mouth, throat, and bloodstream. It is also used to prevent infections in people with weak immune systems, including those with neutropenia due to cancer chemotherapy, transplant patients, and premature babies. In those who are pregnant it may increase the risk of miscarriage. Fluconazole was developed by scientists at Pfizer and was first marketed in 1990. It is now available as an inexpensive generic drug. It is on the World Health Organization's List of Essential Medicines, the most important medications needed in a basic health system.