Question: what is the relationship between the amount of antacid and the length of time to neutralize the acid?
Answer: Doubling the dose of antacid will lengthen only slightly the time during which gastric acidity is reduced. The duration of action can be prolonged by giving an antacid after food. For example, if a dose of antacid is taken at 1 and 3 h after a meal, the duration of effect is prolonged for up to 4 h.