Even though many of the parents I talk to have never had a rectal laxative themselves, they resist giving them to their children because they erroneously believe that they “hurt”. This is unfortunate because there are many children with encopresis who can and do benefit from them.
With PEG oral laxatives, such as Miralax, the time between administration and defecation is slow and unpredictable. Because there is no standard dose, the unpredictable response makes it difficult to determine the most efficacious dose whether it is for conducting a cleanout or for helping a child have a large, soft bowel movement every day without accidents. If we give too little laxative, the child’s stool remains dry and difficult to pass. If we give too much laxative, the child’s stool becomes almost liquid and may “leak” out.
However, the time between the administration of a rectal laxative and defecation is typically very brief, usually within 1-5 minutes, if not immediate. When given correctly (see Chapter 14 of my book), rectal laxatives will empty approximately ¼ of your child’s large intestine thereby reducing the likelihood of accidents.
Another benefit of an enema or suppository is an increase in the efficacy of rewards used to reinforce pooping on the toilet. In other words, the almost immediate bowel movement on the toilet following a rectal laxative allows for an equally immediate reinforcement for pooping on the toilet. As I explain in my book, the immediate and frequent reinforcement of a new behavior leads to faster learning of that behavior than when reinforcement is delayed or infrequent.