Constipation

Side Effects/Problemsa Bloating, flatulence, iron and calcium malabsorption Bloating, flatulence Bloating, flatulence Less bloating Bloating, flatulence Ineffective for constipation Sweet tasting, transient abdominal cramps, flatulence, bloating Incontinence due to potency, bloating, abdominal cramps Rectal irritation, abdominal cramps Irritation Incontinence, hypokalaemia, abdominal cramps Degeneration of Meissner's and Auerbach's plexus (unproven), malabsorption, abdominal cramps, dehydration, melanosis coli Magnesium toxicity, dehydration, abdominal cramps, incontinence Avoid in renal failure Lipid pneumonia, malabsorption of fat-soluble vitamins, dehydration, incontinence Mechanical trauma Accumulated damage to rectal mucosa, hyper-phosphataemia, mechanical trauma Diarrhea, abdominal pain, flatulence and abdominal distension Cardiovascular risk, headache, nausea, diarrhea Nausea, bloating, diarrhea Time to Onset of Action (h) Mechanism of Action — — — — — 12-72 24-48 Non-absorbable disaccharides metabolized by colonic bacteria into acetic and other SCFA which accelerate colonic transit Osmotically ↑ intraluminal fluids 24-48 0.25-1 0.25-1 6-8 h 8-12 8-12 8-12 8-12 2-4 6-8 5-15 min 5-15 min ≤ 7 days 6-24 8-48 Evacuation induced by local rectal stimulation Similar to senna (see anthraquinones) Electrolyte transport altered by ↑ intraluminal fluids; myenteric plexus stimulated; motility ↑ Stool bulk ↑, colonic transit time ↓, GI motility ↑ Mixed soluble and insoluble fiber, stool bulking Stool bulking and softening Fluid osmotically drawn into small bowel lumen; CCK stimulated; colon transit time↓ Stool lubricated Evacuation induced by distended colon; mechanical lavage Prokinetic, guanylate cyclase-C agonist Prokinetic, 5HT4 agonist Intestinal secretion, chloride-2 channel activator 11

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