doubled dose of medication?

My wife is recovering from a back injury she had almost 2 years ago.She has had a back operation and has been in physical theraphy and different medications since the start of rehab.But nothing seems to do well for her and recently whike visiting my mom in the hospital I was leaving to pick my daughter up at work decided to come home to see why my wife or other daughter was not answering the phone.I came upstairs and found my wife with no response called 911 they took her to the emergency room at a nearby hospital was in critical care unit for three days saying her body absorb to much of the narcotic she was using prescribed by the doctor to double the dose she was taking in the begining.She's out of danger home walking with a cane cannot drive until cleared by her primary physician.My wife spoke with one of the police officers who responded to our house said if I had not come home and made the call to 911 she might be dead.