Gastrointestinal drug combinations are often confused by doctors and patients alike as to why sometimes medication does not work. Nowadays, patients are more and more knowledgeable about medicine, and they often want to discuss with their doctors what the drug manuals say and what the Internet says. Doctors are often impatient, who knows more than others? In fact, this kind of discussion is beneficial to both patients and doctors, but in the current volume of outpatient clinics in tertiary care hospitals, this kind of full discussion is very difficult to do because there is not enough time. As a result, the doctor doubts whether the patient’s complaints are objective, and the patient doubts whether the doctor’s diagnosis and medication are correct. The reasons for this can be very complex, and it is difficult to tell without a case-by-case analysis. Here we will only discuss the drug combination for the readers’ reference. There are two aspects to discuss: the skills of drug combination; the best time to take medication. Drugs commonly used in chronic gastritis, peptic ulcer and dyspepsia are divided into four major categories: antacids, acidophilus, gastric stimulants and digestive enzymes. Let’s start with the issue of drug combination. Depending on the patient’s specific condition, the doctor will use one or more of these drugs in combination. Some drugs can be taken at the same time, some must be taken at different times, mainly by the physical and chemical properties of drugs. 1, acid drugs should not be taken at the same time with antacids. Currently, the commonly used omeprazole, esomeprazole, lansoprazole, pantoprazole and rabeprazole are weakly alkaline, their mechanism of action is to concentrate in the high acid environment of the acid-secreting microtubules of the stomach wall cells and strongly inhibit the secretion of gastric acid, if taken at the same time with antacids such as aluminum thioglycollate will reduce the bioavailability of acidophilus, should be taken at intervals of half to hours. According to the study, the commonly used cimetidine, ranitidine, famotidine and other H2 receptor antagonists should not be taken at the same time with antacids. 2, antacids and gastrointestinal stimulants should not be taken at the same time. Antacids such as aluminum thioglycollate or aluminum magnesium carbonate to play a therapeutic role must be attached to the surface of the gastrointestinal mucosa not only neutralize gastric acid and form a protective film on the surface of the gastric mucosa to avoid the erosion of gastric acid, to promote the repair of the gastric mucosa, so I hope that it stays in the stomach for a long time. Gastric stimulants, on the other hand, accelerate gastric emptying. Therefore, when these two drugs are used together, special attention should be paid to the reasonable staggering of the time of taking them. Generally, the gastric prokinetic drugs are taken half an hour before the meal to promote the food group from the stomach into the small intestine, and then half an hour after the meal to take antacids when the rest of the gastric mucosa in full contact with the role. 3, antacids acid making drugs should not be taken at the same time with pepsin. Because the pepsin needs to be activated in an acidic environment, the application of antacids or acid making drugs makes the acidity in the stomach significantly lower, which is not conducive to the role of pepsin. In the case of both hyperacidic gastric disease and indigestion, pancreatic enzymes can be chosen because they are more active in a neutral or weakly alkaline environment. So why do doctors sometimes use the above drugs together? That is because the patient’s different conditions require it. Otherwise it is true that all you need is a robot and you can be a doctor. Patients with chronic gastric disease can have very complex symptoms, from obvious heartburn, to belching, to bloating, to erosion or ulceration of the gastric mucosa, to congestion and inflammation of the gastric mucosa and partial atrophy, to reflux esophagitis and marked dyspepsia, etc. At this time, in order to obtain the most effective treatment, the doctor must apply different drugs according to the situation, or even use drugs that interfere with each other according to their pharmacological effects, in order to achieve the purpose of reducing the patient’s pain as soon as possible. Only the doctor himself knows the pain and suffering involved. Of course, in the patient with more pharmacological knowledge to question, we must patiently explain the reasoning, do not use the tone of authority to refuse to answer. 1. What time to take acid suppressants. It is important to understand the pharmacokinetics of such drugs. Omeprazole (Oxy, Losec), Esomeprazole (Nexium), Lansoprazole (Daclopromide), Pantoprazole (Pantolac), Rabeprazole (Buritaxel, Riport) and other pump inhibitors are rapidly absorbed orally, about 1-2 hours blood concentration reaches its peak, half-life of about 1.3 hours, if taken after meals will affect its absorption but the total amount of absorption remains unchanged. Therefore, it is best to take it on an empty stomach. As for whether to take it in the morning or at bedtime, it should be determined according to the time of each patient’s symptoms, and not uniformly according to the instructions. （In principle, H2 receptor antagonists should also be taken on an empty stomach according to this principle, as to whether to take before or after meals can also be adjusted according to the time of symptoms. 2, antacids what time to take. Currently the most commonly used is aluminum thioglycollate preparations and aluminum magnesium carbonate. Instructions are specified in the meal before taking. This is because many patients’ symptoms appear within 1 hour before meals. However, sometimes the efficacy is not good. There are many patients with stomach pain symptoms not before meals but about an hour after meals, for such patients we should arrange to take the drug about half an hour after meals may be more effective. What is more worth studying is what time is the most appropriate for reflux esophagitis patients to take medication, is it before or after meals, or should it be taken both before and after meals? Because at this time antacids should serve more to protect the esophageal mucosa, and after meals and sleep is the most likely time for the stomach contents to reflux into the esophagus, but that is the antacids taken before meals have long been discharged with food into the stomach or intestines, has not played a role in protecting the esophagus. This may be one of the reasons why many patients with reflux esophagitis are not cured in the long term. There are many other factors that affect the efficacy of gastric disease and need to be discussed by the doctor and patient together.