Dr. Greene’s Answer:
This situation is much more common in normal, healthy, happy children than most people would guess.
When kids begin to have trouble getting to the bathroom and then don’t want others to know about it (hiding dirty panties), the ongoing soiling is unlikely to be for psychological reasons. These kids would go on the toilet if they could, but the urge (if it comes at all) is just too late for them to make it. (This isn’t to discount a psychological association — the loss of control and sense of shame can be quite discouraging for kids.)
The loss of timely urge can come from two almost opposite reasons — with very different ways of handling them!
The most common scenario begins when the child doesn’t stool adequately for a couple of days, for whatever reason (physical, social, or psychological). It might feel too inconvenient at day camp (or school), or perhaps they get a bit dehydrated at some point and stooling hurts. Or they have a virus. Whatever the cause, stool backs up. The colon stretches. The normal urge to stool is lost, and stool backs up further. Soft, liquidy stools make their way around the plug with almost no warning — called overflow incontinence. These unstoppable stools are most common soon after eating — when peristaltic waves normally propel stool onward through the colon.
This situation is tricky because the underlying problem is constipation — even though it looks like urgency or even diarrhea. We call the condition encopresis. Sometimes modifying the diet can result in soft enough stools to break the cycle.
Often, mineral oil, milk of magnesia, or Miralax is needed to get things moving normally again. All three are available over-the-counter in the laxative section of drugstores.
Fecal incontinence may also come from the opposite direction — not a back-up of stool, but from stool moving through too quickly for the child to get to the toilet after the urge. There are a variety of possible causes for these quick stools, including infections (such as giardia) or colitis. Usually, in these cases there would be other symptoms as well.