indication

For the specific and symptomatic treatment of bacterial or protozoal diarrhea and enteritis caused by susceptible organisms.

pharmacology

Furoxone has a broad antibacterial spectrum covering the majority of gastrointestinal tract pathogens including E. coli, staphylococci, Salmonella, Shigella, Proteus, Aerobacter aerogenes, Vibrio cholerae and Giardia lamblia. Its bactericidal activity is based upon its interference with DNA replication and protein production; this antimicrobial action minimizes the development of resistant organisms.

mechanism of action

Furazolidone and its related free radical products are believed to bind DNA and induce cross-links. Bacterial DNA is particularly susceptible to this drug leading to high levels of mutations (transitions and transversions) in the bacterial chromosome.

toxicity

Reactions to Furoxone have been reported including a fall in blood pressure, urticaria, fever, arthralgia, and a vesicular morbilliform rash. Other adverse effects can include a brown discoloration of the urine; hemolysis can occur in G6PDH-deficient patients. The drug has a monoamine oxidase (MAO) inhibitory effect and should never be given concurrently to individuals already taking MAO inhibitors.

biotransformation

Furazolidone is rapidly and extensively metabolized; the primary metabolic pathway identified begins with nitro-reduction to the aminofuran derivative. Two major metabolites are produced: 3-amino-2-oxazolidone (AOZ) or beta-hydroxyethylhydrazine (HEH). AOZ is responsible for monoamine oxidase inhibition. Detoxification and elimination of the drug is done primarily by conjugation with glutathione.

absorption

Radiolabeled drug studies indicate that furazolidone is well absorbed following oral administration

half life

10 minutes

drug interactions

Tetrabenazine: Tetrabenazine may increase the adverse/toxic effects of Furazolidine. Concomitant therapy is contraindicated.

Tolcapone: Tolcapone and Furazolidone decrease the metabolism of endogenous catecholamines. Concomitant therapy may result in increased catecholamine effects. Consider alternate therapy or use cautiously and monitor for increased catecholamine effects.

Tramadol: Tramadol increases the risk of serotonin syndrome and seizure induction by the MAO inhibitor, Furazolidone.

Tranylcypromine: Increased risk of serotonin syndrome. Use caution during concomitant therapy and monitor for symptoms of serotonin syndrome.

Trazodone: Increased risk of serotonin syndrome. Monitor for symptoms of serotonin syndrome.

Trimipramine: Increased risk of serotonin syndrome. Ensure adequate washout period between therapies to avoid toxicity. Avoid combination or monitor for symptoms of serotonin syndrome and/or hypertensive crisis.

Venlafaxine: Increased risk of serotonin syndrome. Ensure adequate washout period between therapies to avoid toxicity. Concurrent therapy should be avoided.

Zolmitriptan: The MAO inhibitor, furazolidine, may increase the serum concentration of zolmitriptan by decreasing its metabolism. Concomitant therapy and use of zolmitriptan within two weeks of discontinuing furazolidine are contraindicated.