Last updated: October 07, 2026
Disclaimer: This content is for informational and educational purposes only. It is not intended to diagnose or treat any health condition, and it does not replace professional medical advice. Always talk with your pediatrician before starting, stopping, or changing any treatment for your child.
Constipation Causes All Sorts of Problems
If your child has a hard time going number two regularly, you know how much it affects their quality of life. It can cause abdominal pain, bloating, and low appetite; it can also bring on irritability, behavior changes, and even bedwetting.
As an integrative medicine physician, my job is to look for the root cause, and very often that root cause starts in the gut. A functioning digestive system is foundational to overall health; when waste backs up, it can create a breeding ground for unwanted bacteria (dysbiosis) and yeast overgrowth, and it keeps the body from clearing what it needs to eliminate. So one of the first things we focus on is simply getting things moving.
Constipation in children is more common than many parents realize. Up to 30% of kids experience some degree of constipation; it accounts for roughly 5% of all pediatric visits and about 25% of visits to pediatric GI specialists.
In medical school, many of us were taught to reach for Miralax first and to refer to a gastroenterologist if that did not work. Over the years, though, I have grown less comfortable giving it to my own kids, largely because of the questions parents keep asking me. Let me answer the big ones honestly.
Is Miralax Plastic?
Here is the short answer to the question so many parents search: “Is Miralax plastic?” Not exactly, but the confusion is understandable. The active ingredient in Miralax is polyethylene glycol 3350, or PEG 3350. PEG is a synthetic polymer derived from petroleum, and because many plastics are also made from petroleum, people often shorthand it as "liquid plastic."
The important distinction: PEG 3350 is fully soluble in water and is designed to pass through the digestive tract, drawing water into the stool so it is easier to pass. It is not a solid plastic, and in most people it is minimally absorbed. So while the "it's basically plastic" framing is a stretch, it is true that the ingredient is a synthetic, petroleum-sourced compound rather than something that occurs in nature.
Does Miralax Have Plastic in It? Does It Have Microplastics?
Two closely related questions come up constantly: does Miralax have plastic in it, and does Miralax have microplastics? To be precise:
- Miralax does not contain solid plastic pieces; it is a powdered polymer that dissolves completely in liquid.
- The "Miralax microplastics" concern usually conflates the polymer nature of PEG with environmental microplastics, the tiny plastic fragments found in water and food; these are not the same thing, and there is no evidence that Miralax is a source of microplastic particles.
- What the product has been shown to contain, at trace levels, is a different concern entirely, which I cover next.
So if your worry is literal microplastics, that specific claim is not supported. The more documented issue involves manufacturing impurities.
The Antifreeze Impurity Question
In 2008, the FDA tested several batches of PEG 3350 laxatives after receiving reports of children with symptoms resembling ethylene glycol ingestion. Ethylene glycol (EG) and diethylene glycol (DEG) are compounds also used in antifreeze. The testing confirmed small amounts of EG and DEG in the lots examined; the FDA characterized these as impurities from the manufacturing process. Because PEG is essentially a chain of ethylene glycol units, some researchers have asked whether PEG might break down into EG and DEG in the body, though that question has not been definitively answered.
What the FDA and Researchers Have Said
It is worth being fair here, because the picture is genuinely mixed:
- Miralax (PEG 3350) is FDA-approved for adults for occasional constipation, for up to seven days at a time; it is not FDA-approved for children, so pediatric use is off-label.
- Even so, major pediatric groups have long considered PEG 3350 a first-line option for childhood constipation, and many studies report that it is effective and well tolerated.
- At the same time, parents filed thousands of reports, and in 2014 the FDA funded research at the Children's Hospital of Philadelphia to study whether young children absorb PEG 3350 and whether it relates to neuropsychiatric symptoms such as anxiety, tics, or mood changes; that research set out to investigate the reports, and it did not establish that the product causes these effects.
In other words, PEG 3350 is widely used and helps many children, and the serious harms remain unproven; yet the open questions are real, and I understand why families want a gentler option. If your child is currently using a laxative a doctor prescribed, please do not stop it on your own; talk with your pediatrician first.
A Gentler Alternative: How Magnesium Can Help
We are on a mission to improve the health of children and families through cleaner products, so we went looking for a gentle, naturally sourced way to support regularity. The turning point was a study in the World Journal of Gastroenterology that evaluated magnesium oxide in children being treated for functional constipation; reassuringly, blood magnesium stayed within safe limits even with daily use. You can read the study here: Serum magnesium concentration in children with functional constipation treated with magnesium oxide.
Here is why magnesium is such a gentle choice. Magnesium is a mineral your body already uses every day, not a synthetic compound. When it comes to regularity, much of the magnesium oxide in Mag-Go is not absorbed into the body; instead, it stays right in the intestine and gently draws in water. That extra water softens the stool and encourages a comfortable, natural bowel movement, and then the magnesium simply passes out of the body. In other words, it works with the gut to help things move along rather than forcing them; think of it as a gentle flush, not a harsh push. The smaller amount that is absorbed is used like any other dietary magnesium, and the research above found that blood levels stayed within a safe range.
Our goal was a magnesium powdered drink that is safe, gentle, and genuinely great tasting. The first two were the easy part. The hard part was flavor: magnesium oxide on its own tastes like a mix of chalk and baking powder, and no child is going to drink that. After close to a year of testing textures, flavors, and natural sweeteners, Mag-Go was born.
Here is what makes Mag-Go different:
- It uses magnesium oxide in the studied dose (600 mg) as the active ingredient.
- It works gently by drawing water into the stool; because most of it is not absorbed, it is eliminated along with that extra water.
- It is enhanced with vitamin C, stevia, and natural flavors, with no artificial colors or sweeteners.
- It comes in a Mixed Berry flavor kids love and an Unflavored version you can stir into your child’s favorite juice or beverage.
- It supports daily regularity rather than forcing it.
For whole gut support, many families pair Mag-Go with our Children's Chewable Probiotic. You can also see how it stacks up in our guide, Mag-Go vs Natural Calm.
Frequently Asked Questions
Is Miralax plastic, and does it have plastic in it?
The active ingredient, PEG 3350, is a petroleum-sourced polymer, which is why it is sometimes called "liquid plastic." It does not contain solid plastic, and it dissolves fully in liquid; still, it is a synthetic compound rather than a natural one.
Does Miralax have microplastics?
There is no evidence that Miralax contains environmental microplastics. That concern typically confuses the polymer chemistry of PEG with the microplastic particles found in the environment; they are not the same thing.
How does magnesium help kids go?
Magnesium works gently in the gut through a natural osmotic action: the portion that is not absorbed stays in the intestine and draws in water, which softens the stool and encourages a comfortable bowel movement. It helps things move along rather than forcing them.
Is magnesium a safe alternative to Miralax for kids?
Magnesium is a mineral the body uses every day, and much of the magnesium oxide in Mag-Go is not absorbed; it gently draws water into the stool and is then eliminated. In a World Journal of Gastroenterology study, blood magnesium in children taking magnesium oxide stayed within safe limits. As with any change, confirm the right approach for your child with your pediatrician.
SHOP NOW: A Cleaner Way to Help Kids GO
Ready for a gentle option your child will actually drink? Try Mag-Go Magnesium Powder in Mixed Berry or Unflavored, or browse the full Mag-Go collection to find your family's favorite.
Shop Mag-Go now and help your kids GO, naturally.
**Reference: Tatsuki, M., Miyazawa, R., Tomomasa, T., Ishige, T., Nakazawa, T., & Arakawa, H. (2011). Serum magnesium concentration in children with functional constipation treated with magnesium oxide. World Journal of Gastroenterology, 17(6), 779 to 783. https://www.wjgnet.com/1007-9327/full/v17/i6/779.htm