When does the medicine Antacid work well before or after consuming food is a question that many have asked and the reply everyone got is the doctor knows the best. So, in order to know the answer to it we first need to understand the basic functions of our digestive system. Which means how our body digests, what our body digests, what happens after and before digesting any food? In the first stage, when we get hungry we feel a burning sensation in our stomach which is caused by the hydrochloric acid and to stop that hunger we consume food.