Nearly 200 types of medicines are in store on the International Space Station, which are essential for the health risks astronauts must face. However, a major challenge for the proper functioning of the medicines is to filter out the effects of microgravity and cosmic microwave background radiation, not to mention the time factor and distance, and the possible supply of the medicines. ‘Space-proof’ medicines will be key factors in the success of future long-duration space missions, as well as new innovative procedures from which terrestrial medicine can also benefit greatly. Can we print medicines halfway to Mars, and why is microgravity an ideal environment for bioprinting?
Many people raised the question of the impact of space on the human body on 28 March 2025, when Sunita Williams and Barry Wilmore returned from the International Space Station after nine months instead of the planned eight days, and 59-year-old Williams looked visibly older than she did before her launch in the summer of 2024. While there is currently no correlation between greying and microgravity, it has long been known that astronauts undergo several physiological changes: time spent on the ISS orbiting 400 kilometres from Earth causes bone and muscle loss, weakens the immune system, and has a negative impact on the circulatory system.
What works well on Earth may not work well in space
“Because of the health challenges astronauts face, the availability of appropriate medicines is crucial on the International Space Station, where more than 190 types are kept in stock, and the ISS crew takes an average of four different medicines a week, mainly painkillers, decongestants and sleeping pills,” said Dr. Szilárd Pál, pharmacist, assistant professor, and head of the University of Pécs Faculty of Pharmacy Institute of Pharmaceutical Technology and Biopharmacy.
He pointed out that the use of medicines in space had already begun during the first manned space missions, but that the use of traditional medicines faced new challenges. With the progression of space exploration, it became clear that the pharmacokinetics and pharmacodynamics of medicines in space were different from those on Earth. This is what the rapidly evolving space pharmacology focuses on, the research of which is essential for the success of manned space missions.
One of the biggest challenges is the stability of the medicines. Microgravity, cosmic radiation, and storage conditions can cause faster degradation and loss of efficacy, and medicines can even chemically degrade or produce toxic byproducts during long-duration space missions, which can endanger the health of astronauts. One solution is to develop radiation-resistant packaging using bio-based protective layers (e.g., silk protein coating). 3D printing is also a promising area for producing medicines locally, but it is also worth looking at synthetic biology, which could provide the world with genetically modified plants grown in space that could be used to make medicines.
Time must also be considered in addition to microgravity
“In a previous large-scale study, medicines stored on the International Space Station (ISS) were tested over a 28-month period, and the results showed that more than half of the medicines did not remain stable in space. Physical changes, such as discoloration and phase separation, were observed in 14 of the products, 73% of which did not meet the pharmacopoeial specifications after 880 days in space. The multivitamins did not lose their active ingredient content due to microgravity, but due to the passing of time, so the vitamin supply may be of paramount importance during long-duration space missions. This shows that the shelf-life of conventional medicines in space is questionable, and they need special formulations or locally manufactured medicines for long-duration missions,” emphasized the researcher.
Based on feedback from astronauts on the ISS, another study reported that some medicines are less effective in space. In the case of sleeping pills (zolpidem, zaleplon), the astronauts had to take a second dose the same night in 17-19 percent of the cases. In another report, 13 different medicines were reported by the crew to be either not effective at all or only mildly effective. There have been cases where astronauts have chosen the wrong medication, as physiological changes in space, such as nasal congestion, are not necessarily due to allergies but to a fluid distribution problem. It is therefore suggested that it is not enough to use only terrestrial medicines in space, but that specific pharmacological solutions adapted to space are needed.
Biotechnology and bioprinting also need some room in the spacecraft
The renewed focus on long-duration space missions has put the spotlight on technologies such as biotechnology and bioprinting, which use stem cells to replace dead, sick, or no longer functional tissues or organs. Experiments have already been carried out on the International Space Station to successfully print human cartilage and vascular tissues, and microgravity has allowed for more uniform cell arrangement, which is difficult to achieve on Earth. The technology could therefore pave the way for organ printing in space, which could save lives on long-duration missions.
The technology, which promises to revolutionise healthcare, is also being experimented with in the tissue printing laboratory at the University of Pécs Szentágothai Research Centre. Bioprinting, unlike simple cell culture, can accommodate multiple cells in arbitrary combinations in three-dimensional structures, just like the way living tissues and organs are structured and function.
“Perfecting tissue and organ printing is a challenge for future biotechnologists, and there is still a long way to go. We cannot yet print hearts and lungs, but we can replace certain bones and cartilage. If, for example, a bone is so severely injured in an accident that it needs to be replaced, it is possible to implant the appropriate cells after creating the skeletal structure and then grow a new bone,” said Dr. Judit Pongrácz, full professor and head of the UP Department of Pharmaceutical Biotechnology, and head of the biotechnology bachelor's programme at the Faculty of Pharmacy.
As she said, medical, so-called “red” biotechnology is a multidisciplinary field: physicians, biologists, chemists, pharmacists, and biotechnologists cooperate to succeed. It is also important to mention the field of personalised medicine, which will also be greatly influenced by advances and processes in biotechnology.
“Small tissues can be excellent to test the negative effects of space. One example is examining the effects of radiation, which can track the mutations induced in the tissues of our organs depending on the time spent on the ISS. Namely, we can look at what effects weightlessness has on our organs, which can be studied by looking at the changed molecular environment due to altered tissue metabolism. These could even be used to develop rapid tests that can also be applied in the terrestrial environment, for example, for the early diagnosis of tumours. Moreover, it is probably well-known that the time spent in space and radiation also affect medicines, and that changes in their shelf-life and degradation can also affect their suitability for use or their expiry date. The possible changes in the efficacy of modified medicines can also be tested by using tissue systems on the space station," said Dr. Judit Pongrácz.
Space pharmacology has a lot to offer to terrestrial medicine
Space pharmaceutical research has major benefits not only for space missions, but also for terrestrial medicine, directly contributing to curing diseases on Earth, opening new therapeutic possibilities, and bringing a new era of regenerative medicine.
One of the future goals of this discipline is to develop personalised medication that takes into account the astronaut’s genetic profile and physiological changes, and if it works in orbit, it will work on our planet as well. Research and innovation could also provide the basis for the development of new anti-cancer treatments or more stable pharmaceutical formulations.
Photos:
Lajos Kalmár