medications

• selective serotonin type 4 receptor agonist,
• binds to the enteric receptors initiating the peristaltic reflex.
• normalizes motility and stimulates intestinal secretion
• dec visceral sensitivity
• 6mg b.i.d. before meals 4-6 wks, another 6 wk course prn.
• significant global symptom relief in women with IBS and constipation.
• most effective and preferred medication for abdominal pain and bloating

• decrease stool frequency,
• improve stool consistency,
• no effect on abdominal pain or bloating

decrease the frequency of diarrhea

• severe diarrhea predominant IBS-female
• serotonin type 3-receptor antagonist
• Side effects include constipation (25%) and ischemic colitis

• abdominal discomfort associated with IBS
• 70% rate of anticholinergic side effects
• used cautiously in IBS patients with constipation
• 30-60 minutes prior to a meal

• cisipride and prucalopride
• strong contractions of the proximal colon
• cardiac arrhythmias and carcinogenesis

• increase in the size of the stool bolus
• make the stool softer

deliver a mass of non-digestible substrate to the colon and due to their hydrophilic nature, facilitate the absorption and retention of fluid in the stool

• psyllium (Metamucil, Konsyl),
• methylcellulose (Citrucel),
• calcium polycarbophil (Fibercon).
• Side effects bloating and flatulence.

• cellulose
• lignin
• gums
• pectins, dec SE
• hemicelluloses, dec SE
• polysacharides

psyllium husk (powder or granules), plantain

bran

polycarbophil

powdered karaya gum, 4-10 g/day

• polysaccharide,
• 20-60 mg /d effective laxative
• SE: gas, bloating, cramps, flatulence, fluid losses

• osmotically active sugars or salts
• sucrose based sorbitol and lactulose or nonabsorbable ions

• MiraLAX®, adds osmotic neutral fluid to colon
• polyethylene glycol 3350
• magnesium hydroxide (Milk of magnesia), mg >release of CCK from duo>inc SB motility; high phosphate, impair cardiac contractility, avoid in renal, cardiac and hepatic d.
• sodium phosphate (Fleets Phosphosoda)

• anthracene derivatives:
• senna (Senekot)
• cascara( Pericolace)

• Phenolphthalein derivatives
• Diphenylmethane: Bisacodyl(Dulcolax)

pseudomelanosis coli

• diphenylmethane similar to phenopthalmein
• oral and rectal
• enteric coated.
• 10-15 mg

SE: cramping, melanosis coli

• triglyceride of ricinoleic acid
• acts in SI by pancreatic hydrolysis>dec water and electrolyte absorption > dec transit time
• avoid long term

Mineral oil, lubricant coats the stool bolus, preventing fluid loss, SE-dec absorption of fat soluble vitamins and essential fatty acids, dont use with surfactant, foreign body reaction

Docusate sodium (colace) lowers the surface tension at the stool water interface, allowing greater penetration of the stool with fluid.

docusate (dioctyl sulfosuccinate), sodium, ca, K, inhibit normal water-absorptive capacity of colon, soften stool, do not promote defecation, 1-3 days before effect, 50-250 mg/day, do not give with mineral oil.

• distension (saline enema)
• rectal irritation (soapsuds, bisacodyl)
• physical softening of the stool (glycerine)

• functional constipation 25 µg bid and IBS-C 8 µg bid
• bi-cyclic fatty acid
• chloride channel activator that induces intestinal secretion without elevating serum electrolyte levels
• activates type2 chloride channels in the apical membrane of the intestinal epithelium.
• nausea, diarrhea, and headaches

• constipation
• 17 g x 14 days inc freq BM's