Category Archives: GIT

Laxatives

  Intermittent constipation t/m: best by high fiber diet, fluid intake, regular exercise.

  1. Bulk forming laxatives:
  • indigestible
  • hydrophilic water absorbing colloids & forms bulky gels that distent colon & permits peristalsis.
  • Natural plant products… Psyllium, methylcellulose & synthetic fibers, polycarbophil increased bloating, flatulence with plant … Bacterial digestion within the colon.
  1. Stool softeners or surfactant agents:
  • Rectal or oral
  • docusate & glycerin suppositories.
  • Mineral oil a viscous oil lubricating fecal material & prevents water absorption from the stool. Long use impairs absorption of fat-soluble vitamins  (A,D,E, K)
  1. Osmotic laxatives:
  • For prevention small doses mixed with juice.
  • PEG for complete colonic cleansing before GI endoscopy.
  • Adequate hydration needed.
  • Mg citrate & Na phosphate.
  • Sorbitol & lactulose non absorbable sugars to treat or prevent chronic constipation. Metabolized by colonic bacteria. Produces cramps & flatulence.
  • MgOH(milk of magnesia) falls under this category but is not for renal impaired patients.
  • osm lax are soluble but nonabsorbable which increases stool liquidity by increasing fecal fluid.
  • Fecal water is isotonic throughout colon.
  • Stimulant lax: 
  • aloe, senna.
  • Lubiprostone a prostanoic acid derivative…for Chronic constipation & IBW, opioid induced const.
  • Acts by stimulating type 2 Chloride channel in small intestines, increasing chloride rich fluid secretion in intestines & increases motility.
  • Causes nausea & is not for pregnant women.
  • Not very effective, constipation returns after stoppage & no efficacy on long term.