ConstipatioN and fecal impaction

This issue is rarely talked about among parents, yet it’s the most common condition we end up treating on a regular basis. It also leads to so much confusion that it’s worth a deeper dive into what it is, where it comes from, and why it matters. Finally, we'll go over how this is treated.

What is it?

The simplest way to think of it is that “constipation” describes symptoms (such as hard stools or irregular bowel habits), whereas “fecal impaction” describes a physical state of the colon (impacted with feces). Note that you can have constipation without impaction (e.g. stools come out hard but never get stuck), you can have impaction without constipation (e.g. 5 days worth of feces stuck in colon, but normal feces continue to go around it and come out regularly) or you can have both (5 days of feces stuck in colon AND hard/dry stools).

Constipation is easy to detect: if your child doesn’t poop every day, or has irregular habits, hard/dry stools, etc., they are constipated.

Fecal impaction is difficult to detect, and unfortunately the more serious of the two. There may be symptoms of constipation, or it may be silent. Additional symptoms might include urinary issues (bed wetting, accidents, UTI), abdominal pain, vomiting, sleep or behavior issues, diarrhea or anal leakage/stool accidents. So how do you know if it's present? It takes a combination of physical exam, a thorough bowel and diet history, family history, and if suspected, either an x-ray and/or trial of disimpaction to confirm it.

Where does it come from?

Constipation is typically related to habits and/or genetics: diet (especially refined grains and dairy), inadequate hydration, inadequate exercise, sedentary habits, or family history.

Fecal impaction is trickier. Colon function is in a delicate balance. When disturbed for any reason during childhood it can easily get tipped off balance and spiral into a vicious cycle. As a common example, children often withhold stool, whether due to temporary causes of constipation above or behavioral reasons (discomfort or embarrassment). They might skip a bowel movement, or simply retain a part of each poop over time instead of letting the whole thing out - you’d never know it. But the longer any feces remain in the colon, the more water the colon will extract from it. So this fecal mass progressively gets drier, harder, and larger. It becomes increasingly difficult to poop this out, and the movement of other feces can become impaired by it. This can slow down transit through the colon, causing more feces to get stuck just like a traffic jam, gradually increasing the size of the mass. But you still may not know it's happening as most feces may continue to go around the impaction and can even come out normally.

The next stage is neuromuscular. If the colon's muscles are left in a stretched out state by retained feces, they will no longer be able to fully contract. This will cause them to lose their strength and ability to push even normal feces through at a normal rate. At this point, the colon can no longer pull itself out of the hole it got itself stuck in without significant help. Finally, our brain senses when we need to poop by listening to stretch receptors in the wall of our colon. If the colon were alternately filling and emptying, the brain would be able to tell the difference between these two states. But if it remains full at all times, the brain rewires itself to ignore the constantly firing stretch receptors, which have lost all meaning. In some cases the only way a child can tell they need to poop is when the poop actually starts coming out, and they may need to rush to the bathroom or have an accident.

Why does this matter?

Childhood is a critical time for the development of organs and establishing their form and function. If the neuromuscular function of the colon is impaired from developing properly, it can result in life long problems with bowel function that spill over to other organs and general health. Direct complications include pain/discomfort, irregular/unpredictable defecation, fecal soiling and incontinence, increased severity of gastrointestinal infections, and damage to the bowel and anal structures (hemorrhoids, fissures, even rectal prolapse). Indirect complications are also common and include urinary issues (bed wetting/incontinence, UTI), appetite suppression, poor growth, vomiting, sleep disruption, and emotional/behavior problems. There are also long term health associations such as an increased risk of colon cancer, appendicitis, and diverticulitis.

One other reason to address this is because of other conditions such as celiac or inflammatory bowel disease which can overlap with the symptoms of constipation and/or impaction. We can reassure ourselves that there isn't something more serious underlying a child's GI symptoms if they respond well to disimpaction. If they don't, it may be a signal that we should investigate further.

Fortunately, both constipation and impaction are treatable, and as it turns out, addressing this common problem is one of the highest yield things you can do to improve your child’s quality of life and health. Read on!

How do we treat constipation and impaction?

Constipation is fairly straightforward. As long as impaction is not present, you simply adjust lifestyle factors until symptoms resolve. Add fiber, increase hydration, limit sticky/starchy foods, limit sedentary activities and increase exercise. Please see our nutrition page for more detail about fiber; you can also add supplemental fiber such as fiber gummies, ground flax seed, psyllium husk, etc.

Fecal impaction is more complicated. If we are proceeding with treatment we will send you detailed instructions. But it will help to understand the basic concept:

  1. Remove the impaction. This is accomplished with a series of 1-3 oral cleanses that combine a high dose osmotic laxative (makes stool loose) with a stimulant laxative (pushes it out).

  2. Rehabilitate the neuromuscular function. This is primarily accomplished by use of a daily laxative for around 9-18 months. The impaction may be gone, but the neuromuscular dysfunction is still present: the colon is dilated, the muscles are weak, and the neural pathway to the brain is not fully operational. A good analogy is the following: imagine you lifted a 20 pound weight every day. But one day, someone straps a 50 pound weight to your hand and you can't lift it; your hand remains stuck at your side. If I come across you a year later, remove the weight and place a 20 pound weight back in your hand, your weakened arm would not be able to lift it - it would remain stuck at your side indefinitely. I would need to go down to a 5 pound weight, where you could actually start lifting it every day again, and gradually increase the weight until you were once again able to lift 20 pounds, maybe a year later.

    The 20 pound weight is like a normal diet - a weakened colon is not yet strong enough to move it, so it will simply get stuck again. Taking a laxative makes the stool lighter and easier to move, just like the 5 pound weight. Now the colon is exercising once again and restrengthening itself. As it strengthens and the neural pathway eventually wakes back up, we can gradually increase that weight until finally it can handle a normal diet without re-impacting - only at this point is the issue is finally solved. Like the weight, it is a very slow process and commonly takes around a year or so of rehabilitation.

    Understandably, many parents get frustrated and want to try and take this faster or stop sooner. But this is a slow and steady wins the race kind of thing, there are no shortcuts just like how you can't go from lifting 20 pounds to 50 pounds overnight. Almost invariably, cutting this process short is like strapping that 50 pound weight right back on, you go back to square one and have to start all over again.

We hope this helps explain the rationale behind treatment of constipation and fecal impaction. Please let your doctor know if you have any further questions or see our FAQ below.

A few other good resources about this include the book “It’s No Accident” by Steve Hodges, MD - a pediatric urologist, and the short video “The poo in you” from the Children’s Hospital Colorado. Note: the video was developed for children with fecal soiling, but even if your child doesn't have this issue the underlying process is very similar and it can help both children and parents understand how fecal impaction occurs in general.

Frequently Asked Questions:

When is an x-ray warranted vs going straight to trial of disimpaction?

If symptoms and/or physical exam are obvious, it's usually best to go straight to a trial of disimpaction. Even when they're not, while a disimpaction is not the most fun way to spend your weekend, it is typically the lowest risk of the two options as well as the most affordable. When symptoms or physical exam are not obvious, or if disimpaction trial is likely to be very traumatic or difficult, an x-ray can provide evidence of dilation of the colon and/or amount of fecal burden. It can also be helpful for families to physically see for themselves what only our experience tells us is present. The main downsides of an x-ray include the cost as well as radiation exposure. While the radiation exposure from a single is not supposed to be too worrisome, we always like to limit this unless necessary. Also, x-rays are not 100% accurate.

How do we know when our child is ready to wean off the laxative?

This is the million dollar question. It's a bit of an art. Too soon and it could all recur and you'd need to start over from scratch. But on the other hand no one wants to do months more of treatment than necessary. The best choice is to come in and see us if you think you're ready, and we can guide you. If you think you're ready for this final appointment, here are a few general guidelines we use to figure out when that should occur:

  1. 9-18 months is a typical range for chronic issues.

  2. For shorter durations/more acute issues, it's usually safe to limit treatment to the length of time the issue has been present, if known. For example if you're pretty certain the impaction has only been there for a month, there's a good chance you can resolve it in a month. Problem is, it's hard to know how long it's been present!

  3. All symptoms and irregularities should be resolved. If your child is still having symptoms or irregularity - sometimes drier, sometimes looser, frequency/quantity varies a lot day to day - they are not ready.

  4. All lifestyle habits should be in place: high fiber diet, consistent hydration, regular exercise habits, no potty fears, limited sedentary activities, and regular stooling.

  5. Let the symptoms guide you, rather than trying to be ahead of your child's readiness. Instead of seeing if your child can *tolerate* a lower laxative dose, watch until you see a need to lower the dose in response to their stools becoming looser.

Are osmotic laxatives safe?

Yes - current research finds they are as safe as, if not safer than, most other medications used in pediatrics. And this shouldn't be surprising; the whole reason they work in the first place is that the molecules are not absorbed, so if you drink 8 ounces of it you poop 8 ounces of it. There are a few studies looking at the safety and effectiveness polyethylene glycol 3350 (PEG - the ingredient in Miralax), none of which have found any significant adverse effects, and it tends to be better tolerated than other alternatives such as Senna, fiber + fructose, etc.:

Why have people questioned its safety? Well, we should question the safety of everything we use. In this case, there also happens to be a lot of urban myth being spread around, but no one has ever produced any evidence harm. Some are confused by making an erroneous comparison between polyethylene glycol 3350 (PEG) and ethylene glycol (EG - an ingredient it antifreeze) because the names sound similar. However, chemistry doesn't work that way. Similar sounding names and even similar molecules can have completely different effects and safety profiles. A single atom can make the difference between something harmless and something toxic, it doesn't mean there's any risk of even partial harm.

In fact, we know what the safe blood levels of PEG are, and a recent study evaluated whether ongoing PEG use is likely to exceed these levels in children. They measured the blood levels of kids taking PEG and compared them to kids who weren't taking it. Interestingly, some kids who weren’t taking PEG had higher levels of certain compounds than some of the kids who were taking it. This is likely because these compounds are found in many other things too. So while there were some variations as you would expect, the total amount remained in a safe range and disappeared completely in less than a day. Based on published reports of toxicity thresholds and levels for safe consumption from the Agency of Toxic Substances and Disease Registry, if you took the smallest child in this study and used the highest level of compounds that this study was able to detect, she would have had to consume 40 capfuls of PEG every day for a full year to exceed safe levels. So that's not likely to be an issue.

One common concern we hear is about some parents who have reported behavior changes after giving their children PEG. In our experience, it actually tends to help with behavior, although there can be a temporary worsening of behavior as you are trying to ease an impaction out if it is stuck - that should make sense. Many kids are simply far more impacted than anyone realizes, and there is a strong connection between the gut and emotions in children. When you take a child who is full to the brim with feces and suddenly give them a bunch of laxative, things may get worse before they get better! If the laxative has nowhere to go and the impaction is severe it might simply expand the impaction - you can bet they feel pretty uncomfortable. Sometimes they even vomit in addition to acting out. We are usually able to avoid this at our clinic by simply taking things slower. Rather than jumping into a disimpaction, we like to "presoften" the impaction for a week or more and then ease into the disimpaction once they're ready for it. Sometimes doing an enema or suppository can also help in these cases so the plug is eased out from below instead of only pushing on it from above. With this precaution, parents tend to report improvement in behavior with treatment rather than worsening.

Nonetheless if you would prefer other options for laxatives, let your doctor know and we can guide you through the various options available.

Same-day appointments

For urgent needs, same-day appointments are available Monday through Friday. Please call as early in the day as possible, the more notice we have the easier it is to fit everyone in. 

Need help outside of office hours?

Firstly, if your child has an emergency, please call 911 or go directly to the ER - they will contact us if needed once your child has been evaluated.

Urgent Care centers can also be helpful when something needs to be seen outside of office hours but it's not an emergency. 

For our list of preferred Urgent Cares and ERs, see our resources page.

And if you have something that might need urgent attention but you're not sure/don't know what to do, we can help: