I did not take DGL with a prescription PPI when I took it. If you were given DGL by a natural physician, check with them. Your regular doctor who prescribed the Aciphex most likely wouldn't know the answer because most MD's don't believe in herbal supplements; but a natural physician would know. If you are taking DGL because you heard it was good for GERD, then your other alternative is to check with a pharmacist. I'd be a bit leary about taking advice regarding the mixing of a prescription and herbal supplement on an internet board.
Good luck, I hope you find an answer.