My 89 Year Old Mother Was Just Put On This

My 89 year old mother was just put on this medication. Should she take this on a daily basis or only when her reflux bothers her mainly at night time? She was experiencing a heaviness in her chest (no pain) and her Dr. originally put her on Nitro pills (3 pills every 5 min) which she would take when these symptoms occurred. She was put through numerous tests and her heart is fine. They finally dx her w/ acid reflux and I explained to her NOT to continue w/ the Nitro pills but the reflux medication. Thank you for any feedback you may have.