A ten-year study tracked 85 astronauts over 4,000 nights of sleep on Earth and 4,200 nights in space. Researchers found that astronauts have high usage figures for sleeping drugs such as Ambien.
PBS.org describes the study more in-depth:
78 percent of the shuttle crew reported taking Ambien (zolpidem) and zaleplon, both powerful sleep drugs, on more than half the nights they spent in space. Similarly, 75 percent of subjects on the ISS claimed they took the medication at some point.The study concludes that more effective measures are needed to encourage rest during space flight. Although NASA schedules personnel for 8.5 hours of downtown per night, it was found that the average length of sleep was around 6 hours.
The Boston Globe quoted a researcher on some of the concerns surrounding widespread sleeping pill usage:
“The concern is if there’s an emergency situation and crew members have just taken hypnotics, they might not perform as well. You have to weigh the benefits of hypnotics against those risks,” said Dr. Laura K. Barger, the lead author and an associate physiologist in the Brigham’s Division of Sleep and Circadian Disorders. “We need to have better countermeasures to improve sleep.”
NASA, which funded the study, issued a statement, saying, “Our astronauts work in harsh, complex environments where they are sometimes subjected to uncomfortable and high stress situations. The agency works hard to identify and implement countermeasures that can ensure astronauts are able to get the same quality and quantity of sleep in space as they do on Earth. . . . The agency is committed to sending humans farther into space than ever before and we need to fully understand the implications of that prior to embarking on a mission to Mars.”
