There's quite a range of antacids on offer at the local chemist to treat heartburn and indigestion, and much of it should be taken with caution.
The antacids will paradoxically increase more stomach acid, thus creating a vicious circle, and so any relief will be merely short term.
Treatments range from sodium bicarbonate, magnesium hydroxide, magnesium salts and aluminium hydroxide, and they're marketed as Asilone, Dijex, Gastrils, Algicon, Alu-Cap, Aludrox, Maalox, Mucogel, Gelusil, Rennie's, Kolanticon and Gaviscon to name but a few.
Aluminium hydroxide should be taken in moderation because the aluminium can enter the blood stream, and there may be a link with osteoporosis and Alzheimer's, particularly if it is taken for a long time.
Magnesium is potentially toxic, particularly if you have kidney problems, while sodium bicarbonate can produce carbon dioxide on contact with the stomach which can add to any flatulence already present.