HI and welcome to the GERD forum.
Instead of laying flat u may want to elevate the head of ur bed and allow gravity to help keep the acids down where they belong....sleeping on ur left side can aid digestion too.
U will want to modify ur diet and lifestyle....in addition to taking meds....there are certain foods u want to avoid...and some that are safe to have...see the list in the Health Pages .....
http://www.medhelp.org/health_pages/list?cid=236
Once u r on a med for GERD u should not just stop taking it as u will have what is known as rebound, the symptoms just come back as the meds stop the acid from being produced so u feel better and heal....but, if u stop taking them ur body will go back to producing the acids and many times over produce them...u should slowly step off the meds to help avoid this.And have a healthy diet in place and a way to relax and reduce stress in ur life....