The main role of the three yellow tablets is to clear heat and detoxify and drain fire and laxative, so it should be taken before and after meals, but if it is taken before meals may be better, because after eating the stomach will be a lot of secretion of stomach acid, stomach acid can degrade the nature of some drugs, so it can affect the efficacy of the drug. The efficacy of the drug will be better if taken before meals, but if the patient himself has underlying diseases of the stomach, such as chronic gastritis, some drugs may cause stomach pain if taken on an empty stomach, so if the stomach is uncomfortable patients are still recommended to take after meals, if taken after meals will not have a stimulating effect on the stomach, but it is recommended to take half an hour after meals will be better.