Furazolidone

What it is and how it works

Furazolidone is a nitrofuran whose reduced reactive intermediates damage bacterial DNA and interfere with several bacterial enzyme systems. It is active against many enteric pathogens, including Escherichia coli, Salmonella, Shigella, Vibrio cholerae and Giardia lamblia, and acts mainly within the gut lumen. It also inhibits monoamine oxidase.

Indications

Bacterial and protozoal diarrhoea and enteritis, including giardiasis and cholera; it has also been used in combination regimens for Helicobacter pylori eradication. Its use has been withdrawn or restricted in many countries.

Dosage and administration (summary)

Oral, usually 100 mg four times daily for adults, for a short course (commonly 2–7 days, up to 10 days for giardiasis).

Contraindications

Hypersensitivity to nitrofurans, infants under 1 month (risk of haemolytic anaemia), and concurrent use of alcohol.

Warnings and precautions

Furazolidone causes a disulfiram-like reaction with alcohol and, through MAO inhibition, interacts with sympathomimetics, tyramine-rich foods, antidepressants and other MAO-interacting drugs, risking hypertensive crisis. Haemolysis may occur in G6PD deficiency; nausea, vomiting, headache, hypersensitivity reactions and dark yellow-brown urine may occur.

Pregnancy

Avoid in pregnancy, particularly near term, because of the risk of neonatal haemolysis.

Storage and supply

Store below 25 °C, protected from light; suspension should be protected from freezing.

Source: reference summary prepared from the EU SmPC/EPAR, BNF and WHO Model Formulary. The approved product information in Iran governs.