The sleep aid Ambien may inadvertently increase the risk of brain disorders like Alzheimer’s disease by allowing toxic proteins to accumulate in the brain, according to a recent study.

Research published on January 8 in the journal Cell revealed that zolpidem, the active ingredient in Ambien, suppresses a natural system responsible for clearing protein waste during dreamless sleep. This system, known as the glymphatic system, plays a critical role in removing harmful proteins, such as tau and amyloid, which are linked to Alzheimer’s disease.

The study highlights potential risks associated with certain sleep medications. Dr. Maiken Nedergaard, co-director of the University of Rochester Center for Translational Neuromedicine and senior author of the study, emphasized the importance of natural sleep for brain health. “The study calls attention to the potentially detrimental effects of certain pharmacological sleep aids on brain health, highlighting the necessity of preserving natural sleep architecture for optimal brain function,” Nedergaard said in a press release.

Researchers used brain imaging and electrical recordings in lab mice to investigate how the glymphatic system operates during deep sleep. They discovered that norepinephrine, a brain chemical linked to stress and arousal, drives rhythmic constrictions of blood vessels independent of the heartbeat. These oscillations power the glymphatic system, enabling it to clear away toxic proteins.

“These findings, combined with what we know about the glymphatic system, paint the whole picture of the dynamics inside the brain, and these slow waves, micro-arousals, and the norepinephrine were the missing link,” explained lead researcher Natalie Hauglund, a postdoctoral fellow at the University of Oxford.

The study also found that zolpidem disrupts these norepinephrine-driven oscillations, impairing the glymphatic system’s ability to remove waste. Researchers caution that further studies are needed to assess whether long-term use of zolpidem and similar sleep aids could increase the risk of dementia or Alzheimer’s disease.