Thin air’s effects aren’t confined to the physical plainpicture/Aurora Photos/Beth Wald

A so-called “smart drug” intended to boost cognitive performance also seems to protect the brain from altitude sickness, according to a military study that tested it at 4000 metres.

An increasing number of people visit high-altitude sites nowadays, for work, sport, religious pilgrimages and military tasks. But even the fittest among us suffer in thin air: the lower oxygen content at altitude can lead to cognitive effects, including memory loss and attention difficulties.

There is little you can do to prevent these symptoms other than acclimatise – but this takes time and doesn’t always work. A drug called oxiracetam might be the answer.


Up and down

ShengLi Hu at the Third Military Medical University, Chongqing, China, and her colleagues took men from the military up to 4000 metres above sea level.

All of the men lived in towns around 1800 metres above sea level. During the study, they spent eight days at this altitude, before climbing for three days to reach 4000 metres, where they stayed for up to a month.

Twenty participants took 800mg of oxiracetam three times per day for the first 15 days of the study, while another 20 men received no intervention. The men performed tests of attention and memory at the start and end of the study and 20 days in, by which time they had been at 4000 metres for nine days.

While all participants experienced a drop in cognitive ability at 4000 metres, those who took oxiracetam showed a much smaller decline than the control group.

Using a technique that measures the brain’s response to sounds, the team found that those who took the drug also showed less of a decline in the speed at which they could process sensory information.

Going with the flow

Blood flow measurements indicated that at high altitudes, certain parts of the cerebral circulatory system contracted and dilated in a way that promoted blood flow to the brain stem. This isn’t surprising, since the brain stem plays a critical role in the maintenance of basic vital signs.

The team also found that the brain stem received blood at the expense of brain areas responsible for more advanced cognitive functions. But in people who took oxiracetam, more arteries dilated, so blood flow throughout the brain was increased. This may be how the drug seems to lessen cognitive problems associated with low oxygen. It is yet to be seen whether diverting the blood in this way could have any negative effects in the long run.

“The results are striking and imply that oxiracetam may be beneficial for helping to mitigate cognitive deficits caused by altitude,” says Timothy Hales at the University of Dundee, UK.

Despite a wealth of people admitting to taking numerous kinds of smart drugs to improve their memory or focus, there is little research on oxiracetam in healthy people. In a single study in older adults with dementia, the drug appeared to help improve performance in some memory-associated tasks.

Oxiracetam is not licensed for medical use in the UK, but the drug is known to be a mild stimulant, says Hales. “Coca leaves have been used by native Andeans for centuries to overcome altitude sickness and this is attributed to their modest cocaine content. So perhaps it is not surprising that benefit can be derived from another, albeit mild, stimulant.”

Journal reference: Brain and Behaviour, DOI: 10.1002/brb3.762