Key Takeaways
- According to a new study, your body position may affect how well the medications you take by mouth are absorbed.
- The closer a pill lands to the lowest part of the stomach, the faster it can dissolve and empty into the top of the small intestine.
- Lying on the right side is the best position for faster dissolution of a medication. Lying on the left side is the worst position.
Taking medications orally usually means thinking about factors that could affect how well it will work—for example, taking it without food versus having it with a meal, or always taking it at a certain time of day.
But have you ever thought about how your body position could affect your meds? When you’re taking pills, are you usually still lying down in bed, sitting at the breakfast table, or standing at the counter waiting for your coffee to brew?
According to a recent study published in the journal Physics of Fluids, the position of your body when you swallow a pill might actually affect how well it’s absorbed.
Assume the Position
Researchers at Johns Hopkins University found that when a pill is taken by mouth, body posture and position can have a big influence on how fast the medicine is absorbed.
“If you’re standing upright or you’re lying down and leaning to the right, then the pill lands very close to the end region of the stomach,” Rajat Mittal, PhD, senior author of the study and a professor of mechanical engineering at Johns Hopkins University, told Verywell. “As a result, it dissolves pretty quickly.”
However, “if you lie down and lean to the left, that’s the worst possible position in terms of dissolving the pill quickly.”
For the study, the team used a model that’s based on the realistic anatomy and structure of the stomach—aptly named “StomachSim.”
Through the magic of physics and biomechanics, the simulator can imitate what is happening inside a human stomach as it digests food—or, in this case, medicine.
The team tested four postures and body positions for taking medicine orally:
- Standing/sitting upright
- Lying on the back
- Lying down turned to the right
- Lying down turned to the left
The simulation showed that taking pills lying down on the right side was the best position because it allowed the drug to flow into the deepest part of the stomach. Once there, the meds dissolved twice as fast as they did when they were taken sitting upright.
On the other hand, lying on the left side or leaning to the left was the worst position to be in—it took up to five times longer to absorb pills compared to when they were taken in an upright posture.
Could Body Posture Really Affect Pills That Much?
According to Mittal, posture would have a big effect on how pills dissolve because the stomach is asymmetric. The organ curves from the left to the right side of the body (it kind of looks like a bean).
A pill is also slightly heavier than the contents of the stomach (which Mittal pointed out is primarily made up of water).
“Because of gravity, the pill will tend to settle down towards the direction of gravity,” said Mittal. “So, depending on which way you’re leaning, whether you’re standing up or lying down, it can really affect where the pill lands in the stomach.”
Jason Gallagher, PharmD, a clinical professor at Temple University’s School of Pharmacy and a Clinical Pharmacy Specialist in Infectious Diseases at Temple University Hospital, told Verywell that most pills do not start working until the stomach releases the contents of the capsule into the intestine.
According to Gallagher, if a pill lands very close to the lowest part of the stomach—the exit, more or less—the faster it will start to dissolve and empty its contents into the top of the small intestine.
“In the stomach, it typically dilutes into a liquid and then keeps going through the gastrointestinal tract,” said Gallagher. “Most of the drug is absorbed in the small intestine for most medications. The amount of time that they spend in various parts of the GI tract can affect their absorption.”
Thanks to gravity and the natural unevenness of the stomach, it makes sense that the position you’re in when you take a pill could affect how it makes its way through your GI system.
Who Benefits From Changing Position?
Mittal said that taking pills standing upright or lying straight back would still work and would be good second choices—especially considering that these positions are common in older adults, people who are sedentary, or patients who are bedridden.
“Lying back actually turns out to be not that bad,” said Mittal. “It’s not as good as being upright, but it’s still somewhat reasonable.”
To get a better sense of how much influence body posture could have, the researchers also looked at how stomachs that are not functioning at full strength affect the dissolution of pills.
Specifically, the researchers modeled what happens when someone has gastroparesis, a condition where the stomach does not empty food as it should. The slowed gastric emptying can be caused by diabetes or happen after viral infections.
Based on the results of the simulation, the effect of body posture on pills in the stomach was similar to the effect of diseases like gastroparesis.
“When we compared how much posture affected pill dissolution and how significant gastroparesis affected pill dissolution, we found the two were very comparable,” said Mittal. “So in some sense, the effect of posture and the dissolution of the pill is kind of equivalent to having fairly severe gastroparesis.”
What the Study Missed
The research is interesting but the study did have some limitations. For one, the researchers did not look at how pills might behave in the stomachs of people of different ages and sexes. They also did not factor in other disorders that can slow down the emptying of the stomach.
“Everybody’s stomach is different,” said Mittal, “From children, elderly, adults, men and women…all of our organs are very unique in size and shape.”
According to Mittal, the team wanted to “keep things simple,” for their study so they “assumed a single and same shape for all the different simulations.”
Mittal also pointed out that some people “have surgery (e.g., gastric surgery) or any kind of other condition that completely changes the way their stomach behaves,” and that the team has not looked at such cases in their research.
Should You Switch Positions to Take Pills?
The study found that lying on the right side was the most effective at dissolving pills, but experts say that does not mean the average person should change how they take medication.
“I think they should change nothing at all,” said Gallagher. “We don’t need medication to be absorbed faster because it’s already been designed in a certain way.”
Mittal agreed.
“Pills are also designed with a normal kind of posture in mind—and the normal posture that a pill is designed for is standing upright and being upright,” he said. “[You can] be cognizant of the fact that your body posture matters, but in almost all cases, being upright will always work very well.”
What This Means For You
While a new study using a simulation of a human stomach showed that certain body positions might be better for breaking down oral medications than others, do not change the way you take your pills without talking to your provider.
Source: Verywellhealth
