Apparently, as with many things in life, taking pills is a matter of attitude. A US research team uses computer simulations to find out in which position it is best to swallow a pill so that it takes effect as quickly as possible.

Ibuprofen, acetaminophen, or aspirin: These pain relievers, as well as most other medications, come in pill form. This makes them easier to administer than, for example, by injection. At the same time, however, this also means that they have to travel a long way in the human body before they take effect. Scientists at Johns Hopkins University have investigated whether the time it takes to take effect can be accelerated by how you take the pill.

For their study, which was published in the journal “Physics of Fluids”, Rajat Mittal’s team developed a computer model that realistically reproduces the shape of the stomach, but also its contractions and the flow of gastric juice. Because: The faster a tablet passes through the stomach, the faster it can work. But “the gastric contractions generate pressure and shear forces that lead to complex transport paths of a pill,” the researchers write.

For their test, they reconstructed the path and dissolution time of a typical painkiller. They simulated four different postures when swallowing: standing upright, lying on the left or right side, or lying on your back.

The simulation showed that the posture when taking the pill can accelerate the effect by about an hour, but can also delay it, depending on the position in which the pain pill is taken. The research team writes that lying on the right side of the body is not the most favorable position, as one would probably assume. This is because the pill was dissolved more than twice as quickly as in a sitting or standing position.

The reason: when standing or sitting, the upright posture slows down the transport of the tablet because gravity brings it to a region with less favorable gastric juice currents. It therefore takes longer for it to reach the stomach outlet on the lower right. According to the study, the pill can reach the stomach outlet even worse if you take it lying on your left side. The effect only sets in after more than 100 minutes, since the tablet has to be transported “uphill” against gravity on its way to the stomach outlet. The researchers conclude that this body position can hinder the absorption of the active substance to a similar extent as some diseases of the gastrointestinal tract.

“We were very surprised that posture has such a large impact on how quickly a pill dissolves,” writes study author Rajat Mittal. When patients swallow painkillers while lying on their right side, gastric contractions, currents of gastric juice, and gravity work together optimally to rapidly propel the pill to the anus and dissolve it. In the computer simulations, it often took only ten minutes for the painkiller to reach the duodenum – about 2.3 times faster than when the patient was standing upright.

“Especially for older people who are less mobile or even bedridden, the correct lateral position can be of considerable importance,” writes Mittal. Nevertheless, he and his team limit the validity of their study somewhat. Computer simulations are very useful, but very simplified models of complex processes. How much liquid, gas and food is in the stomach can also affect digestion. Therefore further investigation is needed.

(This article was first published on Wednesday, August 17, 2022.)