An unexpected danger of insomnia medication has been identified

Australian scientists have found that low doses of quetiapine, which is frequently prescribed for insomnia, do indeed help people sleep longer and wake up less often during the night. However, the very next day, the drug noticeably impairs reaction time, attention, and driving skills.

The study was published in the Annals of the American Thoracic Society (AATS).

Quetiapine is officially intended for the treatment of schizophrenia and bipolar disorder. Nevertheless, in practice it is often prescribed in small doses to people with insomnia and anxiety due to its pronounced sedative effect.

Researchers from Flinders University decided to examine how safe this approach is. They paid particular attention to patients with obstructive sleep apnea — a condition in which breathing periodically stops during sleep. Many of these individuals also suffer from insomnia and complain of frequent nighttime awakenings.

The study involved 15 adult volunteers. Each of them spent two nights in a sleep laboratory: in one case, participants took 50 mg of quetiapine, and in the other — a placebo. After overnight monitoring, the scientists assessed sleep quality, and in the morning they tested attention and the ability to operate a vehicle using a specialized simulator.

It turned out that after taking the drug, participants did indeed sleep more efficiently and experienced fewer breathing interruptions during sleep. At the same time, blood oxygen levels did not deteriorate. However, the positive effect was accompanied by a noticeable decline in daytime performance.

In people who had taken quetiapine, reaction time was slower, lapses in attention occurred more frequently, and vehicle control during driving simulation worsened. All of these indicators are considered important risk factors for road traffic accidents.

What particularly concerned the scientists was that some participants did not feel notably drowsy, even though objective tests showed a decline in their cognitive abilities.

"The discrepancy between how a person feels and how they actually function creates a serious safety risk, especially when driving," noted lead study author Cricket Fawska.

As a safer alternative, the researchers recommend cognitive behavioral therapy for insomnia and more thorough screening of patients for sleep-disordered breathing before prescribing sedative medications.