Adverse events were similar between the three groups , the most common being headache reported by @ ( @ % ) of @ patients enrolled in placebo group , @ ( @ % ) of @ patients in the low-dose group , and @ ( @ % ) of @ patients in the high-dose group , or diarrhoea , reported by seven ( @ % ) patients in the placebo group , four ( @ % ) patients enrolled in the low-dose group , and @ ( @ % ) patients in the high-dose group .