From the Guidelines
Polyethylene Glycol (PEG) is safe for treating constipation during the first trimester of pregnancy, as it is minimally absorbed by the body and works locally in the gut to soften stool. According to the most recent and highest quality study, a 2024 clinical practice update on pregnancy-related gastrointestinal and liver disease published in Gastroenterology 1, PEG-based laxatives are recommended as a treatment option for constipation in pregnant persons. The study notes that constipation may be experienced by 20%–40% of pregnant persons and that PEG can be administered safely during pregnancy.
Key points to consider when using PEG for constipation during the first trimester include:
- The typical dosage is 17 grams of powder (about 1 heaping tablespoon) dissolved in 8 ounces of water, taken once daily
- Brand names include MiraLAX, GlycoLax, and ClearLax
- PEG can be used throughout pregnancy as needed for constipation relief
- Before starting any medication during pregnancy, it's essential to consult with your healthcare provider
- While using PEG, ensure adequate fluid intake and consider dietary modifications like increasing fiber intake (25-30 grams daily), staying physically active as appropriate, and establishing regular bathroom routines.
It's also important to note that PEG is preferred over stimulant laxatives during pregnancy because it works locally in the gut without systemic absorption, making it less likely to affect the developing fetus or cause uterine contractions, as supported by the 2024 study 1. In contrast, older studies such as the 2014 US multi-society task force on colorectal cancer 1 provide less relevant information on the use of PEG during pregnancy, making the 2024 study the most reliable source for guidance on this topic.
From the FDA Drug Label
IF PREGNANT OR BREAST-FEEDING, ask a health professional before use. The FDA drug label does not answer the question.
From the Research
Safety of PEG for Constipation in the First Trimester
- The safety of Polyethylene Glycol (PEG) for constipation during the first trimester of pregnancy has been evaluated in several studies 2, 3.
- A study published in 2004 found that PEG-4000 was effective in treating constipation in pregnant women, with 73% of participants experiencing resolution of constipation symptoms 2.
- Another study published in 2020 compared the safety and efficacy of PEG 4000 and lactulose for the treatment of constipation in pregnant women, and found that both treatments were effective, with PEG 4000 having a faster therapeutic effect 3.
Recommendations for Treatment
- The American College of Gastroenterology recommends that osmotic laxatives, such as PEG, be used for the treatment of constipation in pregnant women, but only for short-term use or occasional use to avoid dehydration or electrolyte imbalances 4, 5.
- A study published in 2007 recommended that medications be avoided during pregnancy, but if necessary, should be taken under supervision using the best available evidence 6.
Key Findings
- PEG 4000 has been shown to be effective in treating constipation in pregnant women, with a significant increase in evacuation episodes per week and improvement in constipation symptoms 2, 3.
- The use of PEG 4000 has been found to be safe for pregnant women, with no significant differences in adverse effects compared to lactulose 3.
- The short-term use of osmotic laxatives, such as PEG, is generally recommended for pregnant women with constipation who do not respond to dietary changes or bulking agents 4, 5.