Medications used to treat astronauts in space may not work as well as they do on Earth because of the nature of human spaceflight, a new study finds.
The drugs appear to lose some of their potency in space, possibly because they are exposed to the unique elements of space travel, including increased radiation and excess vibrations, researchers said. Future studies should work to develop special packaging and formulations of medications in order to ensure they do not degrade when they are in space for long periods, they added.
"This is a first step toward preparing for future, beyond low earth orbit flights," study researcher Lakshmi Putcha, of the NASA Johnson Space Center in Houston.
Astronauts may require medications in space to treat minor illnesses, such as aches and pains, motion sickness and sleeping problems. Drugs sent into space are packed into special containers certified for flight and stored in flight kits.
Drugs in space
Astronauts do undergo a period of quarantine before space travel to prevent catching any infectious illnesses prior to their flight, but that doesn't stop them from experiencing some of Earth's everyday ailments during a mission.
Currently, medications aboard the International Space Station are replaced every six months to make sure they stay effective, Putcha said.
But scientists won't always have this option as missions travel farther from Earth, for instance, on a years-long trip to Mars, Putcha added. [ 6 Everyday Things That Happen Strangely in Space ]
To test the limits of medications in space, Putcha and her colleagues built eight identical kits. Four were sent to the International Space Station while the others were stored in special chambers with controlled temperature and humidity at the Johnson Space Center.
Each kit was equipped with devices to measure radiation exposure as well as changes in temperature and humidity.
Space medicines falter
After 28 months, the medication stored in space generally had a lower potency and degraded faster than those stored on the ground. Six medications on the space station underwent physical changes, such as discoloration and liquefaction, while such changes only occurred in two medications stored on the ground.
The medications in space were exposed to higher levels of radiation than those on the ground, but temperature and humidity was about the same.
Putcha and her colleagues detailed their research in the April 9 issue of the Journal of the American Association of Pharmaceutical Scientists.
The next step, the researchers say, is to test medications on Earth in an environment designed to mimic that on spacecraft in order to better understand the stability of these drugs, as well as the byproducts that form as they degrade. Such experiments could also help researchers figure out ways to augment the medications for space travel, they added.
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