Abdominal cramps bisacodyl

Dulco-lax tablets containing bisacodyl, a stimulant laxative, must be swallowed whole with water and not chewed to decrease occurrence of abdominal cramps. 

Castor oil is broken down in the small intestine to ricinoleic acid, which is very irritating to the gut and promptly increases peristalsis. Cascara, senna, and aloe contain emodin which stimulates colonic activity. Onset of activity is delayed 6 to 8 hr because emodin is excreted into the colon after these agents are absorbed. Emodin may pass into breast milk. Phenolphthalein and bisacodyl are also potent stimulants of the colon. Adverse effects include abdominal cramps and the potential for atonic colon with prolonged use. 

Bisacodyl increases peristalsis by a direct effect on the small intestine. Its only specific adverse effect is abdominal cramping, which a minority of patients find troublesome. As with other laxatives, however, heavy or chronic use can derange the system in various ways, for example hypokalemia with rhabdomyolysis (SEDA-16, 425). 

Comparative studies A high oral dose of bisacodyl (30 mg) plus water lavage (2 liters) and oral sodium phosphate (90 ml in divided doses) has been evaluated in a randomized study in 276 adults undergoing elective colonoscopy [73 ]. There was more nausea in those who took sodium phosphate compared with bisacodyl (28% versus 7%). There were no significant differences between the two groups in overall tolerance (95% versus 96%), vomiting (4% versus 2%), or abdominal cramps (31% versus 34%). 

Gastrointestinal tract Bisacodyl stimulates colon motility, causing abdominal pain and cramps, and has been associated with ischemic colitis [81" ]. 

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