When we encounter physical discomfort or pain, every minute of waiting for painkillers to take effect is not only physical torture, but also spiritual torment. For a long time, we can only endure and endure, waiting for the medication to take effect. Recently, research has found that we may be able to accelerate the effects of medication and relieve pain more quickly by placing ourselves in a specific position, which is right side lying. Have you ever thought about how to take medicine and get results the fastest? Scientists have noticed since 1918 that when subjects lie to the right after taking barium meal (an oral contrast agent used for diagnosing the digestive tract), their gastric emptying rate increases. This discovery has sparked ongoing research in the scientific community on posture effects, with the aim of revealing the underlying physiological mechanisms. Before exploring how posture affects drug efficacy, we need to first understand the absorption process of oral drugs in the body. After taking the medication, it reaches the stomach through the esophagus, is dispersed, dissolved, and diluted under the action of digestive fluid, and then enters the small intestine. This transfer process from the stomach to the duodenum is called gastric emptying. For the vast majority of drugs, the degree of gastric absorption can be negligible. The main absorption area of drugs is the upper part of the small intestine, especially the duodenum, due to its broad absorption surface and sufficient blood supply. Drug molecules pass through the intestinal wall and enter the bloodstream in the small intestine, and finally reach the target tissue or organ through the bloodstream to exert their therapeutic effects. The geometric shape of the stomach when lying in different postures (A) upright (B) prone (C) right lying (D) supine (E) left lying. There are many factors that affect the absorption of drugs in the gastrointestinal tract, including drug dissolution and release rate, gastrointestinal environment, intestinal absorption surface area, gastrointestinal secretion and peristalsis, local blood flow, and diet. To study how posture and position affect the onset time of drugs, it is necessary to understand how these direct factors will change under different postures. How does posture and position affect the effectiveness of medication? The gastric emptying process is an important rate limiting step in the early stage of oral drug absorption. Taking the common antipyretic drug acetaminophen as an example, the average absorption time of half of the drug in the small intestine is about 6.8 minutes, while the average time of half emptying in the stomach is about 12 minutes. Based on this, scientists began to study how posture affects the duration of liquid and solid retention in the stomach. A study conducted by Anwari et al. from McMaster University in Canada found that lying on the right side can accelerate gastric emptying compared to sitting and standing positions, while lying on the left side and lying on the back often lead to mixing, dilution, and slower gastric emptying. Golub and others from Kaifu Pharmaceuticals in the United States believe that this phenomenon is caused by changes in gastric volume and fluid distribution under different postures. Generally speaking, the larger the volume of the stomach, the faster the emptying rate, and the maximum volume of the stomach is maintained when lying on the right side. In addition, when lying on the right side, the pylorus connecting the stomach and duodenum is in a lower position, and gravity can accelerate gastric emptying. When lying on the left or lying on the back, with the pylorus facing upwards, gravity cannot accelerate the gastric emptying process. Changes in body position can also affect the flow and distribution of blood in our body. When we transition from lying down to sitting or standing, our blood is subjected to the force of gravity