When you take the medicine half an hour after eating, the digestion of food is basically finished, the amount of stomach acid is reduced, and the ingredients in the medicine can be absorbed smoothly and the gastrointestinal function is utilized. When the medicine is taken immediately after a meal, the drug is mixed with food and transported to the small intestine in paste form, and the drug is absorbed through the stomach in order to play an important role. When it is mixed with food and transported to the small intestine, it cannot play its own role and loses the efficacy of the drug. Therefore, the medicine should be taken half an hour after consuming the meal to allow the medicine to work better. Half an hour after the meal, taking the medicine can reduce the stimulation of the gastrointestinal tract and facilitate the absorption and utilization of the medicine. Using food, reduce the stimulation of drugs to the gastrointestinal tract, and promote the absorption of drugs by the stomach and intestines. For example, aspirin and flavopiridol are suitable to be taken after meals to reduce the stimulating effect on the gastrointestinal tract.