Constipation Management Guideline

First-Line Agents

The American Gastroenterological Association recommends polyethylene glycol (PEG) as the preferred initial osmotic laxative for chronic idiopathic constipation, with moderate certainty evidence 1, 2.
PEG has demonstrated durable response over 6 months in clinical trials, providing confidence for long-term use 2.
Bisacodyl and sodium picosulfate have strong recommendations with moderate certainty evidence for short-term or rescue therapy (≤4 weeks daily use) 1, 2.

The American Gastroenterological Association recommends linaclotide, plecanatide, and prucalopride as second-line prescription agents with strong recommendations and moderate certainty evidence 1, 3.
Linaclotide and plecanatide were studied for 12 weeks, while prucalopride was studied for 4-24 weeks 1, 3.

Lubiprostone receives only a conditional recommendation with low certainty evidence, despite FDA approval 1, 4.
Lactulose receives a conditional recommendation with very low certainty evidence, limited by bloating/flatulence side effects that restrict clinical use 2, 5.
Magnesium oxide receives a conditional recommendation with very low certainty evidence, with trials conducted for only 4 weeks 2.
Senna receives a conditional recommendation with low certainty evidence 1.

PEG demonstrated 6-month durability, supporting extended use 2.
Stimulant laxatives (bisacodyl, senna) were studied for only 4 weeks, while prescription agents (linaclotide, plecanatide, prucalopride) were studied for 12-24 weeks 1, 2, 3.

Diarrhea rates from linaclotide and plecanatide lead to treatment discontinuation, informing patient counseling 1.
Dose-dependent nausea with lubiprostone can be mitigated by taking with food and water 1.
Bloating and flatulence with lactulose and fiber are dose-dependent and may limit clinical utility 2, 5.
Prucalopride's lack of cardiac QT effects distinguishes it from withdrawn agents like cisapride—critical safety data 3.

Start with PEG 17g once daily as first-line osmotic laxative, with moderate certainty evidence 2, 4.
Add bisacodyl or sodium picosulfate for rescue therapy if needed, with moderate certainty evidence 2, 4.
If inadequate response, escalate to prescription agents with strong evidence, such as linaclotide, plecanatide, or prucalopride 1, 3, 4.
Reserve conditional-recommendation agents, such as lactulose and magnesium oxide, for specific scenarios 2, 5.