Clinical trial of clonidine hydrochloride as an antisecretory agent in cholera

Clonidine hydrochloride (an α2-adrenoceptor agonist) was tested for antisecretory effects in patients with cholera in a randomized controlled trial. Nineteen adults with diarrhea due to Vibrio cholerae were treated with clonidine (0.9 mg/24 h orally for 72 h) and 18 served as controls. During the first 24 h of treatment and for 24 h afterwards, the mean ± SD concentrations of sodium (in millimoles per liter) in the stools of clonidine-treated patients were 120.6 ± 10.9 and 112.3 ± 11.9, which were significantly lower than 135.5 ± 17.1 and 125.0 ± 16.4 in the controls (p < 0.01). Stool chloride concentrations (in millimoles per liter) were also significantly less in the clonidine group during the same periods: 82.1 ± 16.8 and 62.4 ± 19.4 vs. 92.1 ± 18.3 and 78.0 ± 23.0, respectively (p < 0.05). Concentrations of potassium but not bicarbonate were also significantly reduced in the stools of clonidine-treated patients (p < 0.05). However, there were no significant differences in the mean ± SD stool volumes (in liters) between the clonidine and the control group in any of the six 12-h periods after treatment or in the cumulative volumes in 72 h (24.2 ± 10.6 and 22.9 ± 8.3, respectively). We conclude that clonidine causes modest reduction of stool electrolyte loss but does not significantly reduce fecal fluid loss in patients with cholera.