Thank you for your inquiry.
MiraLAX is polyethylene glycol 3350. There is known cross-reactivity between this agent and psyllium seed, which is the active ingredient in Metamucil. Polyethylene glycol has caused allergic reactions but your patient should not be, based upon any cross-reactivity between MiraLAX and psyllium, at increased risk regarding the administration of MiraLAX.
Thank you again for your inquiry and we hope this response is helpful to you.
Phil Lieberman, M.D.