Treatment

• First-line: nonpharmacological measures (e.g., high-fiber diet, increased fluid intake, and exercise) and/or trial of bulk-forming laxatives

• Second-line: step-wise pharmacotherapy with laxatives from other classes

  • Begin with an osmotic laxative.

  • If symptoms persist, add a short course of a stimulant laxative.

• High-fiber diet: Recommend 20–35 g of dietary fiber daily, from high fiber-containing foods and/or bulk-forming laxatives (e.g., psyllium). [24]

• Hydration: Encourage recommended daily fluid intake.

• Physical activity: Encourage regular physical exercise.

• Healthy bowel habits

  • Schedule toileting for 10–15 minutes in the morning and ∼ 30 minutes after each meal to coincide with the gastrocolic reflex.

  • Use a step stool while on the toilet to raise the legs and straighten the colon.

  • Recognize and respond to urges to defecate.

• Biofeedback: Recommend in patients with defecatory disorders who are able to actively participate.

Introduce fiber slowly (over several weeks) and ensure adequate fluid intake simultaneously to prevent cramping and bloating.

Constipation that worsens with fiber supplementation may suggest slow transit constipation or a defecatory disorder

• Patients taking bulk-forming laxatives and osmotic laxatives should be instructed to ensure adequate water consumption.

• Chronic osmotic or stimulant laxative use may lead to hypokalemia (which can further reduce bowel motility) and metabolic alkalosis.

• Stimulant laxatives should be:

  • Prescribed for short-term use only; chronic stimulant laxative use may lead to dependency.

  • Taken approximately 30 minutes after meals to coincide with the gastrocolic reflex

• Stool softeners (e.g., docusate) should not be used for initial pharmacological treatment because their benefit has not been proven

A group of drugs that improve colonic transit time by increasing intestinal secretion of water, bicarbonate, and chloride. These may be used to manage constipation refractory to other therapies.

• Agents

  • Linaclotide

    • A peptide agonist of guanylate cyclase-C

    • Increases intestinal secretion of bicarbonate, chloride, and fluid, which improves fecal transit

  • Lubiprostone:

    • A prostaglandin derivative that activates chloride channels on the apical surfaces of enterocytes

    • Increases intestinal fluid secretion and improves fecal transit

• Adverse effects

  • Diarrhea

  • Nausea (lubiprostone)

• Fecal incontinence

• Fecal impaction, which may lead to bowel obstruction, or rarely, bowel perforation

• Anal fissures

• Hemorrhoids

• Megacolon

• Urinary retention

• Pelvic floor damage in women

• Rectal prolapse