This medication contains two different medicines: They are called aluminium hydroxide and magnesium hydroxide. They belong to a group of medicines called antacids. Aluminium hydroxide/Magnesium hydroxide suspension is used for: Heartburn or when your stomach has too much acid (indigestion) Inflammation of the stomach (gastritis), and When prescribed by a doctor it may also be used for lowering the amount of acid in your stomach or gut (intestine) when you have an ulcer Aluminum hydroxide/Magnesium hydroxide suspension works by lowering the amount of acid in your stomach.