Can my 2 1/2 year old use miralax (polyethylene glycol) longterm? we believe constipation stems from daily diphenhydramine

If specialist agrees: For chronic constipation in a 2 or 3 year old, some sort of laxative is usually used. Long-term use of any medication in young children is done only if there is not a good alternative. A pediatric gastro-enterologist (specialist for intestinal issues) can evaluate and help decide on the treatment course, especially if a child can't be successfully weaned off a medication in two months.

Yes: Miralax (polyethylene glycol) is not a laxative as the name suggests. It is a non digestible sugar that pulls extra water into the intestine to soften the stool. It can be stopped cold turkey or weaned gradually whenever no longer needed.

Yes: Since it is basically a wetting agent and not a true laxative, its actions are benign. I have used it in a monitored setting for a year with no problems, though most will respond to a good bowel rehab program in 6 months or less.