Caffeine-heavy items include coffee, tea, chocolate, and some sodas. Both irritate the lining of your stomach and both tend to lower esophageal sphincter pressure. When this happens, it's easier for the contents of your stomach to shoot back up into your esophagus. This gets gravity working for you and not against you, and the digestive juices in your stomach are more likely to head south, for your intestine, instead of back up into your esophagus. It is a drug that, in the vast majority of cases, should be used only for occasional relief of mild heartburn or indigestion.
Antacids are fast-acting.
They should bring relief within minutes. If you're taking antacids and there's no relief, then something else may be going on, something that requires a physician's evaluation. Igor Cerny, a pharmacist with FDA's Center for Drug Evaluation and Research, agreed. Two weeks is the general rule of thumb. Beyond that, taking antacids can actually mask a more serious medical problem.