Constipation is a frequent complaint of older adults. Contributing factors include advanced age, decreased physical activity, low caloric, bulk and fluid intake and the presence of multiple illnesses and medications. Many older people are preoccupied with their bowel habits and believe they are constipated. However their concern may be due to a misconception of what a normal bowel movement should be. Normal bowel habits range from 2-3 times a day to 3-4 times per week. The patient should be evaluated thoroughly prior to initiating therapy and any underlying cause should be removed when possible.

Possible Causes of Constipation

Diseases Cancer Diverticulosis Neurologic disease Depression Nutritional Causes Inadequate fiber intake Inadequate fluid intake Medications Antacids (calcium and aluminum compounds) Anticholinergic medications Tricyclic antidepressants Bismuth subsalicylate (Peptol Bismol™) Diuretics Iron Calcium channel blockers Beta blockers Antipsychotics Opiates (morphine, codeine) Sucralfate

The first line of approach to constipation should be increased intake of dietary fiber and fluids.

• Bulk forming laxatives such as psyllium or methylcellulose are the preferred choice for treating constipation in those elderly who have diets low in fruit or vegetable fiber. These agents closely mimic the natural peristaltic movements.
  
• Stool softeners such as docusate sodium (Colace™) can be used in elderly patients who have concomitant illnesses where straining can be deleterious i.e. for patients who have had a heart attack, aneurysm or stroke. Docusate is a surfactant that softens the fecal matter allowing the stool to pass without straining.
  
• Saline laxatives such as milk of magnesia attract water to the intestinal lumen creating increased motility and can be given if the above approaches have not produced the desired results. It should not be given to patients with renal insufficiency due to its potential for accumulation and toxicity.
  
• Mineral oil should be avoided because it can prevent absorption of essential nutrients.
  
• Stimulant laxatives such as bisacodyl (Dulcolax™), phenolphthalein (Ex-Lax™), cascara sagrada and senna (Senokot™) act as irritants and increase peristaltic activity by acting on intestinal nerves and muscle. Chronic use can lead to laxative dependency.
  
• Osmotic agents such as sorbitol and lactulose can be given to patients who have constipation secondary to neurogenic causes. Bulk laxatives are not effective in this population.