Treatment of Constipation

1st line

↑ fluid, fiber, exercise; emollient laxative (docusate) to soften stool.

2nd line:

• Bulk laxatives (psyllium, methylcellulose) to ↑ colonic residue,
• ↑ peristalsis.
• Stimulant laxatives (senna, castor oil, bisacodyl) to ↑ motility & secretion.
• Osmotic laxatives (Mg, NaPO4 [avoid in CKD], PEG) to ↑ H2O in colon.

3rd line:

Enema/suppository (phosphate, mineral oil, tap water, soapsuds, bisacodyl)

After above failed:

• linaclotide ↑ stool freq, ↓ straining/bloating (Am J Gastro 2018;113:105).

• Lubiprostone (↑ secretion); methylnaltrexone and alvimopan for opioid-induced.

• Plecanitide (cGMP agonist) for chronic idiopathic constipation (Gastroenterol 2016;150:S317)