Reduces small intestinal transit time (t50) in healthy volunteers in gamma scintigraphy studies. 0.755 g reduced transit time by 11%, 1.509 g by 23% and 2.264 g by 23%/34% (different studies) [8,9,10]. Cimetidine Cmax and AUC0-24 significantly lower for tablet and solution formulations containing 2.264 g mannitol than sucrose control; AUC reduced by 31% for tablet and 29% for solution; Cmax reduced by 49% for tablet and 54% for solution [