According to http://www.onbedwetting.com
bedwetting alarms are the most effective way of dealing with bedwetting in older children. I have checked out the SleepDoc. In effect it does not wake the child when he or she wets, but jogs them close enough to consciousness to realize that the bladder is filling up. It might work. The only thing I would worry about is that it might cause the child to sleep fitfully.