Indications
Furazolidone is an antibacterial and antiprotozoal medicine taken by mouth. It is used to treat diarrhoea and enteritis (inflammation of the intestine) caused by susceptible bacteria, and giardiasis, an intestinal infection caused by the parasite Giardia. It acts mainly inside the gut.
How It Works
Furazolidone belongs to the nitrofuran group. Inside bacteria and protozoa it is converted into reactive substances that damage their DNA and block important enzymes, so the germs stop multiplying and die. Very little is absorbed into the blood, so most of its action is in the intestine.
Dosage and Administration
Usual adult dose: 100 mg four times a day, usually for 2 to 5 days, or as prescribed. For giardiasis the doctor may advise a course of 7 to 10 days. Children’s doses depend on body weight and should be given only as prescribed. Take with water, with or without food. Drink plenty of fluids or oral rehydration solution to replace water lost through diarrhoea. See a doctor if there is no improvement within 2 to 3 days.
Interactions
Furazolidone has a monoamine oxidase (MAO) inhibiting effect. Avoid alcohol during treatment and for at least 4 days after, as it can cause flushing, fast heartbeat, nausea and breathing difficulty. Avoid foods rich in tyramine (aged cheese, cured or fermented meat, soy sauce, some fermented foods) if treatment lasts more than a few days. Do not combine with antidepressants (such as Fluoxetine, Amitriptyline or MAO inhibitors), Pethidine, decongestants like Pseudoephedrine or Phenylephrine, or amphetamine-like medicines without medical advice.
Contraindications
Do not use if allergic to Furazolidone or other nitrofurans, in infants under 1 month of age, or with known G6PD deficiency unless a doctor advises it. Avoid in people taking MAO inhibitors.
Side Effects
Possible side effects include nausea, vomiting, headache, stomach upset and dizziness. Urine may turn dark yellow or brown; this is harmless. Less often, skin rash, itching, fever, joint pain or low blood sugar can occur. In people with G6PD deficiency it can break down red blood cells (haemolysis).
Get urgent medical help for swelling of the face or throat, difficulty breathing, severe rash, very pale or yellow skin, dark red urine, or a sudden rise in blood pressure with severe headache.
Pregnancy and Lactation
Safety in pregnancy has not been established; use only if a doctor considers it clearly needed, and avoid near the time of delivery. It may pass into breast milk; avoid in breastfeeding mothers of newborns or babies with G6PD deficiency unless advised by a doctor.
Precautions and Warnings
Use for the shortest time needed. Seek medical care if diarrhoea is bloody, very frequent, with high fever, or if signs of dehydration appear (dry mouth, little urine, dizziness). Tell your doctor if you have G6PD deficiency, high blood pressure or take any mood or cold medicines.
Overdose
An overdose may cause severe nausea, vomiting, headache or a dangerous rise in blood pressure. Seek medical help straight away. Treatment is supportive.
Therapeutic Class
Nitrofuran antibacterial and antiprotozoal (intestinal anti-infective).
Storage
Store below 30°C in a dry place, away from light. Keep out of the reach of children.
Prepared by the Oshud Alo team from standard drug references. For information only; always follow your doctor's advice.