Short-term self-treatment of travellers' diarrhoea with norfloxacin: a placebo-controlled study

In a randomized, double blind, placebo-controlled, multicentre trial, 447 travellers to Africa, Asia or Latin America started three days treatment with norfloxacin 400 mg bd or placebo within 24 h after the onset of travellers' diarrhoea. One hundred and four subjects developed diarrhoea and of those 94 (46 in the norfloxacin group and 48 in the placebo group) could be analysed for efficacy. By the last treatment day, 34 patients in the norfloxacin and 18 in the placebo group were cured (P = 0.0001), four and three improved and five and 19, respectively, were failures. Recurrences were seen in three patients on norfloxacin and eight on placebo. The mean time to cure was 3.2 days in the norfloxacin group and 4.4 days in the placebo group (P less than 0.005). The number of loose stools was significantly lower in the norfloxacin group. Nine adverse events were reported; seven in the placebo and two in the norfloxacin group. Pre- and post-travel faecal samples were studied in 19 patients treated with norfloxacin, 21 treated with placebo and 21 untreated subjects without diarrhoea. In treated subjects, increased frequencies of Escherichia coli resistant to ampicillin, co-trimoxazole, doxycycline and chloramphenicol were found in both groups, though more frequently in the placebo one. No subject had norfloxacin resistant Esch. coli pre- and post-travel.