Single dose tetracycline in cholera

A randomised clinical trial was carried out to explore the efficacy of single dose tetracycline therapy in cholera. One hundred and eighteen adult patients were assigned to receive either tetracycline in a single 1 g, or a single 2 g dose, or tetracycline 500 mg every six hours four times, or no antibiotics as controls. The means of total liquid stool volumes after treatment were lower in the single 1 g dose group (168-0±20-9 ml/kg), in single 2 g dose group (229.5±45.6 ml/kg), and multiple dose group (214±28.5 ml/kg), than in the control group (499-1±56-5 ml/kg) (p<0.05). Similarly, the means of durations of diarrhoea and intravenous fluid requirements were significantly lower in the single dose and multiple dose tetracycline groups, than in the controls (p<0-05). The mean durations of excretion of Vibrio cholerae were significantly shortened from 3*9±0-2 days in the control group to 1-9±0-2 days in single 1 g dose, to 2-2±0*4 days in single 2 g dose and 1-3±0X1 days in multiple dose groups, respectively (p<005). Three patients in the single 1 g dose group and two patients in single 2 g dose group had clinical relapses with excretion of V cholerae during the relapses, but this was not significantly more frequent than that in the multiple dose group (p>0-05). These findings suggest that although multiple dose tetracycline therapy remains the best choice, a single dose of either 1 g or 2 g tetracycline appears to be a reasonable alternative for the treatment of cholera as an adjunct to rehydration therapy.