What is the use of MiraLAX (Polyethylene Glycol 3350)?

From the Guidelines

MiraLAX (polyethylene glycol 3350) is the most effective treatment for chronic idiopathic constipation, as evidenced by a recent high-quality study published in 2023 1. The standard adult dose is 17 grams (about one heaping tablespoon) dissolved in 8 ounces of water, juice, or other beverage, taken once daily.

• It typically works within 1-3 days.
• MiraLAX draws water into the colon to soften stool and increase bowel movements without causing cramping or urgency.
• According to the american gastroenterological association-american college of gastroenterology clinical practice guideline, three randomized, placebo-controlled trials studied the effect of PEG on constipation, with two of these studies being multicenter trials conducted in Italy and one in the United States 1.
• The studies showed that PEG is effective in treating chronic constipation, with participants experiencing an increase in bowel movements and improvement in symptoms such as straining, hard stools, and sensation of incomplete evacuation.
• The most recent and highest quality study, published in 2023, supports the use of MiraLAX as a first-line treatment for chronic idiopathic constipation, with a dose of 17 g per day 1.
• Common side effects include bloating, gas, and nausea, but MiraLAX is generally safe for short-term use (up to 7 days) in adults and children over 17, though pediatric use should be supervised by a doctor.
• Unlike stimulant laxatives, MiraLAX isn't habit-forming and doesn't cause dependency.
• People with kidney disease, bowel obstruction, or unexplained abdominal pain should consult a healthcare provider before using it.
• For best results, maintain adequate hydration and increase dietary fiber while using MiraLAX.
• If constipation persists beyond a week of use, medical evaluation is recommended.

From the FDA Drug Label

PATIENT INFORMATION Polyethylene Glycol 3350 NF (Polyethylene Glycol 3350 Powder for Oral Solution) is a prescription only laxative which has been prescribed by your physician to treat constipation. The dose is 17 grams each day or as directed by physician. Polyethylene Glycol 3350 NF achieves its best results when used between one and two weeks. You should not use for a longer time unless directed by your physician

The recommended dose of MiraLAX is 17 grams per day as directed by a physician. It is intended for use between one and two weeks and should not be used for a longer period unless directed by a physician 2.

From the Research

MiraLAX Overview

• MiraLAX is a brand name for the medication polyethylene glycol 3350 (PEG 3350) 3, 4, 5, 6, 7
• It is an osmotic laxative used to treat constipation by increasing the amount of water in the stool, making it softer and easier to pass 3, 4, 5, 6, 7

Efficacy of MiraLAX

• Studies have shown that PEG 3350 is effective in treating chronic idiopathic constipation in adults 3
• A post hoc analysis of a multicenter, double-blind, placebo-controlled trial found that 42% of patients taking PEG 3350 met the US Food and Drug Administration endpoint for treatment of constipation, compared to 13% of patients taking a placebo 3
• Another study found that PEG 3350 was effective in treating occasional constipation, with 36.7% of patients reporting complete resolution of straining and hard or lumpy stools 6

Safety of MiraLAX

• PEG 3350 has been shown to be safe and well-tolerated in both adults and children 3, 4, 5, 6, 7
• Common adverse events associated with PEG 3350 include diarrhea, nausea, bloating, and abdominal pain, but no serious adverse events have been reported 3, 4, 6, 7

Recommendations for Use

• The American Journal of Gastroenterology recommends PEG 3350 as a first-line laxative for the treatment of chronic constipation, based on good evidence 4
• The Journal of the American Association of Nurse Practitioners also recommends PEG 3350 as a first-line laxative, based on an updated systematic review of published data 7