Scientists have found a new obstacle to future manned missions to Mars, involving the shelf life of medicines that astronauts will take with them on their long missions in space.
According to the study, many of the medications that astronauts may take with them are likely to expire before they return to Earth.
Scientists say they have discovered a group of drugs used in space that have a shelf life of three years or less, a problem given that NASA expects a mission to Mars to take about 36 months.
Expired drugs on Earth are usually less effective, although it's unpredictable how effective they will be, said Dr. Dan Buckland, senior author of the study from Duke University School of Medicine.
As a result, astronauts may end up relying on ineffective or even harmful medications.
Buckland and his colleagues have compiled a list of medications on board the International Space Station (ISS). While the specific drugs that will be transported to Mars are not yet known, Buckland said the drugs on the ISS would likely make up the bulk of the medical toolkit for such a mission.
In a research paper published in the journal npj Microgravity, the team revealed how they found shelf-life data for 91 of the 106 medications on the ISS 2023 list, with expiration dates indicating that 54 drugs would expire after 36 months, including some painkillers.
Fourteen drugs will expire in 24 months, including an advanced life support drug, one drug to treat anaphylaxis, two antibiotics, and an antipsychotic.
When the minimum shelf life of each drug was taken into account, 89 out of 106 drugs were found to expire within 36 months.
The authors said the expiration dates refer to the drug in its original packaging, meaning it could be shorter if it is repackaged, as is often the case on the International Space Station.
Previous studies have shown that astronauts on the International Space Station report daily medication use, suggesting their importance. But while the ISS can be regularly resupplied with these medications, this may not be possible for astronauts on long missions, making expiration a concern.