Ok that's not on the list my doctor's office gave me but if you feel you can wait until morning you could just call your office and check with them. They can check without you having to wait for your appointment.
I have never heard of that. The list I recieved from my doctors office has a lot of options for safe constipation relief. It says Benefiber, Citrucel, Colace, Dialose, Fiberall/Fibercon, Metamucil, Milk of Magnesia, and Surfak. If you're on an iron pill or prenatal with high iron taking a couple days break from it can help too.