Furazolidone is no longer available in the US. Though an effective antibiotic when all others fail, against extremely drug resistant infections, it has many side effects, and as with other nitrofurans generally, minimum inhibitory concentrations also produce systemic toxicity (tremors, convulsions, peripheral neuritis, gastrointestinal disturbances, depression of spermatogenesis.) Nitrofurans are recognized by FDA as mutagens/carcinogens, and can no longer be used since 1991.
^Machado RS, Silva MR, Viriato A (2008). "Furazolidone, tetracycline and omeprazole: a low-cost alternative for Helicobacter pylori eradication in children". Jornal de pediatria84 (2): 160–5. doi:10.2223/JPED.1772. PMID18372934.