This Sleep Aid Might Protect Your Brain from Alzheimer’s

Scientists are discovering that sleep might do more than refresh the brain — it could help protect it from devastating diseases like Alzheimer’s. In a recent study from Washington University School of Medicine in St. Louis, researchers found that a sleep aid protects brain from Alzheimer’s-like damage in male mice.

The drug in question is lemborexant, a prescription sleep medication already approved to treat insomnia. But this study showed it also reduced the buildup of a toxic protein called tau — a key player in several neurodegenerative diseases, including Alzheimer’s. Even more exciting, lemborexant helped preserve brain structure and reduce inflammation in regions vital for memory .

What Makes This Sleep Aid Different?

Unlike typical sleeping pills, lemborexant blocks orexin receptors — proteins that control the body’s sleep-wake cycles. Researchers found that mice prone to Alzheimer’s-like tau buildup who were treated with lemborexant had 30% to 40% more volume in the hippocampus, the brain’s memory hub, than untreated mice or those given a different sleep drug like zolpidem .

Zolpidem improved sleep but didn’t prevent the brain damage, highlighting that only sleep aids targeting orexin receptors had this added benefit.

How Sleep Affects Brain Health

Poor sleep has long been tied to increased risk of Alzheimer’s, but this study offers new insight into how improving sleep may slow brain degeneration. In mice with tau buildup, lemborexant helped:

• Reduce inflammation

• Lower toxic tau levels

• Prevent loss of brain cells

• Preserve memory-related brain structures

One surprise: the protective effects were seen only in male mice. Scientists think this might be because female mice naturally had less severe tau-related damage, making it harder to detect the drug’s impact .

What It Means for the Future of Alzheimer’s Treatment

This research adds to growing evidence that improving sleep — specifically through orexin receptor blockers — could be a key part of protecting the brain. While Alzheimer’s treatments currently target another protein, amyloid, this approach could be used in combination with other therapies to better slow the disease’s progression.

Although more studies are needed — especially in humans — lemborexant and similar drugs could represent a promising new direction for early intervention or prevention in neurodegenerative disorders.

Conclusion: A New Path from Sleep to Brain Protection

This discovery opens the door to a broader view of how sleep medications might support brain health beyond their use for insomnia. If future human trials support these findings, lemborexant could become part of a new toolkit for delaying or even preventing Alzheimer’s and related diseases — especially for those at higher risk.

Discover more at interventionalpsychiatry.org

Citations:

1. Parhizkar, S., Bao, X., Chen, W., et al. (2025). Lemborexant ameliorates tau-mediated sleep loss and neurodegeneration in males in a mouse model of tauopathy. Nature Neuroscience. https://www.nature.com/articles/s41593-025-01966-7

2. Washington University School of Medicine in St. Louis. (2025, May 30). Sleep aid blocks neurodegeneration in mice. https://medicine.wustl.edu/news/sleep-aid-blocks-neurodegeneration-in-mice/