It is a problem that affects around 20 percent of 5-year-olds and up to 3 percent of teens. Frequent nighttime bed-wetting can be emotionally devastating for a child of any age, but a new research review shows that most kids don't have to suffer.

According to the analysis, one of the oldest treatments for bed-wetting is also one of the most effective.

Nighttime alarms that vibrate, ring, or light up when a child starts to wet the bed were found to work better to stop bed-wetting permanently than the most widely prescribed drug.

"About 50 percent of children are cured after three to four months of treatment with the alarm," Cathryn Glazener, MD, PhD, tells WebMD. "Alarms are certainly more of a hassle than drugs at first, but they are also much more likely to work long term."

Drug Works Faster

While children who took the drug desmopressen (also known as Concentraid and DDAVP) stopped nighttime bed-wetting faster than those who used the alarms, they were more likely to start wetting the bed again after stopping treatment.

The review was conducted by The Cochrane Collaboration, an independent group that evaluates medical research.

Many children occasionally wet the bed, but the medical condition known as nocturnal enuresis is nighttime bed-wetting that occurs at an age when a child could reasonably be expected to be dry. That age, according to the report, is 5 years old.

Teaching the Bladder

The causes of the condition aren't clear. Delayed or immature development of the bladder may be one factor.

Although most children eventually grow out of bed-wetting without treatment, many suffer for years unnecessarily, Glazener says.

"For some families it is no big deal, but it can potentially be very disruptive to a household and certainly distressing to the child," she says. "When things get to this point, it is time to seek treatment."

Children who are bed wetters are at an increased risk for emotional and physical abuse, says the report.

In some form or another, alarms have been used to stop bed-wetting for almost 70 years. These days the devices are fairly sophisticated and either vibrate, ring, or light up when a special mattress pad senses the first signs of moisture.

"The idea is to wake the child before they have emptied their bladder so they will have to get up and go to the bathroom to finish," Glazener says.

Over time the body becomes conditioned to wake up when the bladder is full.

Half Were Cured

Glazener and colleagues analyzed 55 trials comparing the effectiveness of bed-wetting alarms to treatment with desmopressen and several other therapies that have been less well studied.

Of the 2,345 children enrolled in the studies, two-thirds of those used an alarm for two weeks straight. About half of the children began bed-wetting again after stopping the alarm treatment.

Studies involving other therapies, such as behavior modification and alternative treatments like hypnosis and acupuncture, were generally of poor quality, the researchers noted. As a result, it was not possible to evaluate their effectiveness.

While alarm-based treatments cured about half of the children who used them, another review found that combining alarms with behavioral therapy and medication worked much better.

Researchers Michael Mellon, PhD, of the Mayo Clinic in Rochester, Minn., and Melanie McGrath, PhD, of Tulane University, concluded that the three-treatment approach could cure "closer to 100 percent" of bed wetters.

By Salynn Boyles, reviewed by Brunilda Nazario, MD

SOURCES: Glazener, C. The Cochrane Database of Systematic Reviews, 2005; Issue 2. Cathryn Glazener, MD, PhD, Cochrane Incontinence Review Group; senior research fellow, University of Aberdeen, Aberdeen, Scotland. Mellon, W. Journal of Pediatric Psychology, 2000; vol 25: pp 193-214.