I was somewhat concerned myself about the side effects of polyethylene glycol (Movicol and Miralax) but have found many long time users on this forum with no problems so far. As I understand it, polyethylene glycol is not absorbed by the body.
Besides, I fail to see anything "natural" about magnesium-glycinate-chloride-lactate-carbonate-citrate-oxide-sulfate-hydroxide-taurate-threaonate. They've just been around longer.

Hi, I use miralax too. Miralax is not absorbed by the body at all. It just draws water into the colon to help soften the stool. It is not a stimulant laxative and it is not habit forming. Magnesium is relatively safe when used correctly (low doses) but it can cause serious kidney problems sometimes. I guess it's just what each person prefers to use. To be honest, I'm just glad there is a product like miralax. When you deal with fissures or any painful rectal problem it's nice to know there's something that help keep a bm soft. Suzy