what is the safest over the counter heartburn medicine?
Antacids don't do anything to prevent GERD, but they can be used on demand for symptom relief. They are cheap and available over the counter. Common antacids contain calcium carbonate (Tums, Rolaids) and/or magnesium (Mylanta, Maalox, milk of magnesia), and provide relief of heartburn within 5 minutes.