Need answer asap please. my 10 yr old son takes miralax for constipa. dr said if really constipated give 2xd until regular. he took 2nd dose 2ngt started having cramps(belly discomfort) would that be normal? miralax working?

Maybe the Miralax: A person with constipation needs to be sure there is no other disease causing it. If constipation is just due to slow movement of food and poop through the gut, then the things to try are vegetables, water, prune juice, prunes, fiber with water, Miralax (polyethylene glycol), Senokot or other senna, milk of magnesia, other laxatives, enemas,... If excess cramps, the doctor or ER can evaluate.