Formulations of nitrofurans come in different concentrations of active ingredient. Furacin (nitrofurazone) formulation active levels vary (e.g. 4.5, 9.3 or 11%), but prefuran (nifurpirinal) comes as a 10% active powder.
Nitrofurans are antibacterial compounds used primarily for the treatment of bacterial infections. Although nitrofurazone is not absorbed when fish are treated by bath exposure, the compound has received widespread use as a medication for external abrasions and wounds. However, nitrofurazone administered orally results in systemic drug levels in fish. Prefuran is rapidly absorbed from the water or can be added to the feed. However, prefuran is reported to not be effective if used in a bath treatment in saltwater.
Studies with laboratory animals have revealed that nitrofurans are carcinogenic. Thus, exposure to there compounds is to be avoided and their use as a therapeutant in fish culture is not recommended. These compounds must not be used with fish intended for human consumption.
nitrofurans has not been approved by the Food and Drug Administration (FDA) for use with tilapia. Thus, it is not currently legal to use this substance to treat tilapia especially if these fish or their offspring are intended for human consumption.
nitrofurans may be legally used only if there is a current Investigational New Animal Drug Application (INADA) in effect for treatment of the particular disease at the particular site. It is the responsibility of the user to know if an INADA is in effect for nitrofurans for use with tilapia on his or her site. The user must be familiar with and to comply with the conditions for an INADA for nitrofurans.