Croton grewioides Baill. (Euphorbiaceae) Shows Antidiarrheal Activity in Mice

Based on chemotaxonomy, we decided to investigate the possible antidiarrheal activity in mice of a crude ethanolic extract obtained from aerial parts of Croton grewioides (CG‑EtOH). We tested for any possible toxicity in rat erythrocytes and acute toxicity in mice. Antidiarrheal activity was assessed by determining the effect of CG‑EtOH on defecation frequency, liquid stool, intestinal motility and intestinal fluid accumulation. CG‑EtOH showed no in vitro cytotoxicity and was not orally lethal. In contrast, the extract given intraperitoneally (at 2000 mg/kg) was lethal, but only in females. CG‑EtOH produced a significant and equipotent antidiarrheal activity, both in defecation frequency (ED50 = 106.0 ± 8.1 mg/kg) and liquid stools (ED50 = 105.0 ± 9.2 mg/kg). However, CG‑EtOH (125 mg/kg) decreased intestinal motility by only 22.7% ±4.4%. Moreover, extract markedly inhibited the castor oil‑induced intestinal contents (ED50 = 34.6 ± 5.4 mg/ kg). We thus conclude that CG‑EtOH is not orally lethal and contains active principles with antidiarrheal activity, and this effect seems to involve mostly changes in intestinal secretion.