Why Miralax Clean-Outs Fail

By Steve Hodges, M.D.

Editor's note: This post was updated in 2026 to reflect Dr. Hodges' current treatment guidelines.

The Miralax merry-go-round: clean-out, maintenance dose, relapse… repeat.

The other day I had a routine colonoscopy — fun stuff!

The bowel prep gave me an opportunity to empathize with my patients and to reflect on a question I hear constantly from parents: “Why don’t Miralax clean-outs help my child?”

After all, “clean-outs” are doctors’ go-to treatment for constipation that has escalated to bedwetting or daytime pee or poop accidents.

Families are often instructed to do a big clean-out, follow it with daily “maintenance” Miralax, and repeat as needed.

Sometimes that approach helps. But as a standalone treatment for enuresis or encopresis, clean-outs tend to be a temporary fix at best — and often do nothing except ruin a kid’s weekend.

Worse, families can end up trapped on the Miralax merry-go-round: a cycle of clean-outs, maintenance doses, setbacks, and repeat clean-outs — with no real progress and a child who’s still having accidents.

So why do clean-outs fail? Because they don’t solve the real problem. That’s why, in my clinic, I recommend a different approach: the Modified O’Regan Protocol (M.O.P.).

My colonoscopy prep was a perfect reminder of why.

By “bowel prep,” I mean drinking massive amounts of laxative and sitting on the toilet endlessly while you essentially pee out your bottom.

Or, as the great Dave Barry once described it:

You spend several hours pretty much confined to the bathroom, spurting violently. You eliminate everything. And then, when you figure you must be totally empty, you have to drink more, at which point, as far as I can tell, your bowels travel into the future and start eliminating food that you have not even eaten yet.

By the time I checked in for my procedure, my bowels were, no doubt, 100% empty. For a brief moment, I thought: It’s so easy to get empty! Miralax clean-outs should work great for constipated kids.

Then I remembered a few key details.

For one thing, I wasn’t constipated to begin with. And I had consumed nothing for 24 hours besides clear liquids. In other words: I was the easiest possible clean-out candidate.

The mega-dose of laxative I took didn’t have to accomplish much. It was like taking a shower when you’re already pretty clean.

But kids with enuresis and/or encopresis aren’t dealing with minor constipation. They’re dealing with a large stool mass that has built up in the rectum over months or years — stool that becomes hard, dry, and difficult to dislodge.

For these kids, a Miralax clean-out can be like showering when you’re caked in hardened mud. Even an industrial-strength rinse may not get the job done.

Clean-outs tend to fail in two predictable ways.

Sometimes, the liquid laxative simply washes around the hard stool mass, leaving the child with a miserable combination: diarrhea and constipation.

Other times, the clean-out pushes poop downstream, so now the end of the rectum is even more clogged than before. Accidents may diminish (or even disappear) for a week or longer — and then come roaring back.

One mom in our private support group captured the frustration perfectly:

“I’ve come to believe a clean-out is like a strict diet to lose 5 pounds. The effects are only temporary. It cleaned my daughter out, but as soon as the cleanse was over, she started to fill back up.”

Another mom posted:

“We had major output, like an ice cream machine for DAYS. Then we were on the Miralax merry-go-round for years. Has not helped.”

Here’s the part that often gets missed: in chronic constipation, the stool-clogged rectum becomes stretched and floppy. It won’t spring back to normal quickly — not even after a dramatic clean-out.

On top of that, children with a stretched rectum often don’t reliably feel the urge to poop — or don’t feel it at all. Even when they do feel an urge, withholding has often become automatic.

So even if a clean-out temporarily reduces the stool burden, it doesn’t change the underlying dynamics that caused the buildup in the first place. The child returns to withholding, poop piles up again, and you’re right back where you started.

Families are instructed to do clean-outs repeatedly — sometimes every month or two — as if constipation were an occasional event. But in these children, constipation is chronic. And chronic constipation requires a different strategy.

Early in my career, I regularly prescribed Miralax clean-outs followed by daily maintenance dosing. That was before I grasped how stubbornly clogged these kids tend to be. I also didn’t realize it takes a good three months for the rectum, once successfully emptied, to shrink back to normal size and regain tone and sensation.

Even after that point, many children need temporary help relearning how to respond to the urge to poop. (For these children, Ex-Lax can be a useful tool as they wean off enemas.)

The point is: for children with enuresis and/or encopresis, the Miralax “clean out” is usually a wholly inadequate treatment.

This is where the Modified O'Regan Protocol comes in.

M.O.P. uses daily enemas (to empty the rectum thoroughly), combined with laxatives (to keep stool soft), long enough for the rectum to heal and shrink back to normal size. When the rectum normalizes, the bladder often normalizes too — because the bladder nerves are longer being irritated by a bulging stool burden.

I explain the full protocol, the variations, troubleshooting, and tapering plans in The M.O.P. Anthology.

Doctors tend to push Miralax because they underestimate the challenge of emptying a severely clogged rectum (enemas are viewed as “overly aggressive”) and because they believe enemas are “traumatic.”

Though both assumptions are untrue and uninformed, I hear this constantly. Many parents tell me they go through repeated clean-outs partly to demonstrate compliance with a GI doctor who dislikes enemas or views them as “extreme.”

One mom told me her child did three fruitless clean-outs in a single month for exactly those reasons. “I was being nice with the GI,” she wrote. “I’m not totally surprised it didn’t work, but I had wishful thinking.”

Then her child resumed enemas — because M.O.P. was the only approach that produced sustained progress.

The irony is that repeated clean-outs often cause far more distress than a properly administered enema routine: messy accidents, rashes, discomfort, and the demoralizing sense that nothing works.

This isn’t to say oral clean-outs are never useful. I’m not anti-clean-out.

In fact, in some cases, oral clean-outs, used strategically alongside M.O.P., can help a child off a plateau. Sometimes, stool gets stuck in the upper part of the rectum, where an enema may not quite reach (you can see this on an x-ray). In those cases, a clean-out doesn’t “clean out” the rectum so much as push stool down to where enemas can take over and flush it out.

In other words: oral clean-outs can be a tool — just not the foundation of treatment for most kids with severe constipation and accidents.

As one mom in our support group posted:

“Only when we added in periodic clean-outs to M.O.P. did we see progress. I think they’re helpful, but not as a way to avoid enemas.”

My general philosophy is simple: whatever works. But if your child has been through multiple clean-outs and continues to struggle, that pattern itself is a clue: the approach isn’t addressing the real problem.

The oral laxative super-wash that cleaned me out before my colonoscopy would probably have accomplished little for most of my patients.

If your family is stuck on the Miralax merry-go-round, there is a way off.

READ: The M.O.P. Anthology: The Proven Way to STOP Bedwetting, Daytime Enuresis, Encopresis, and Chronic Constipation in Toddlers Through Teens

READ: Helping Your Child Exit the Miralax Merry-Go-Round (free guide)