Lie right to help the medicine go down

As well as being told when we should eat before and after taking medication orally, new research reveals the exact posture to adopt to make it work better.

The speed a drug enters the blood stream depends on stomach contractions, fluid dynamics and the stomach’s position.

Next time you take an aspirin, try speeding up its effect by lying on your right. But don’t turn over, or you could be waiting a long time for pain relief.

Scientists have modelled the dynamics of the stomach in an attempt to understand how posture can affect drug absorption.

The research, published in the journal Physics of Fluids, adds to evidence that as well as being told when we should eat before and after taking medication orally, we should also be told what posture to adopt. Scientists say the findings are important “especially for bedridden patients or the elderly”.

The speed a drug enters the blood stream depends on stomach contractions, fluid dynamics and the stomach’s position. When people lie on their left, the stomach exit is at its highest point.

For their study Rajat Mittal, from Johns Hopkins University in Baltimore, and his colleagues used a modelled stomach that could be run for a digestive cycle while held in different orientations. The simple effect of gravity was huge. Leaning 45 degrees to the left reduced the rate at which the drug exited the stomach to close to zero.

Standing up meant more drug left the stomach. But leaning back — so stomach fluid could better wash past the pill — increased mixing by 50 per cent. Leaning to the right had an even more pronounced effect, leading to a further doubling of the concentration of active ingredient released.

However, Mittal added: “Some pills are designed to act fast whereas others are designed for slow, extended release. So speeding up the dissolution is not necessarily good in all cases.”

The Times