Last reviewed 01/2018

The side-effects of antacid use include:

  • alkalosis:
    • sodium bicarbonate is well absorbed and may cause alkalosis in high doses
    • aluminium and magnesium are not absorbed and are safer
    • this is a rare problem today
    • historically this was called the milk-alkali syndrome

  • gastrointestinal effects:
    • constipation (aluminium salts) or diarrhoea (magnesium salts)

  • aluminium has been implicate in dialysis dementia and Alzheimer's disease

  • interactions:
    • tetracyclines precipitate out in alkaline solutions
    • L-DOPA absorption is altered by some antacids