Persistent Acid Reflux. Medication?

My mother has been experiencing acidity-related problems for the past couple of years. Her symptoms include a severe headache, vomiting, and loud burping or gas in the stomach, especially in the mornings. One doctor advised her to take an antacid medicine every morning before breakfast. However, I am concerned about her having to take this medicine every day for a long time due to the risk of side effects. We have already done a full body check-up and all results came back normal. She does not have any other known medical problems. Why might she be experiencing these persistent symptoms despite normal test results? Is there a permanent cure or more effective long-term solution for her acidity and gas problem instead of continuous medication?