Does Ambien Increase Dementia Risk? What the Research Really Shows

Sleep is essential for brain health, but one of the most commonly prescribed medications for insomnia — Ambien (zolpidem) — has raised questions about whether it affects dementia risk. Researchers are still debating the answer.

Sleep medications are often overprescribed in the United States. According to a recent report from the National Center for Health Statistics, 15 percent of surveyed adults had trouble falling asleep as of 2024, and nearly 13 percent used sleep aids to help them fall or stay asleep. Use of sleep aids also increased with age.

Zolpidem is a Z-drug, a class of medications called sedative-hypnotics that depress the nervous system, commonly used for short-term treatment of insomnia. Zolpidem works by enhancing the activity of GABA, the brain’s primary calming neurotransmitter, helping people fall asleep more quickly.

The medication is available as a tablet, extended-release tablet, or oral spray. Guidelines suggest taking it immediately before bedtime due to its quick effects. Users are also advised to plan for a full night’s sleep of seven to eight hours since waking up too early can bring side effects, such as drowsiness and dizziness. 

More serious side effects include unconscious sleep behaviors, like walking or driving, and short-term memory problems according to the Food and Drug Administration.

Scientific research on Ambien use

Ambien reduces the time it takes to fall asleep, but the quality of sleep differs from normal sleep, affecting memory and potentially slowing toxin clearance.

There is conflicting research on the effects of Ambien on cognition. A recent community-based study out of Iwate Medical University in Japan found that Z-drugs were associated with cognitive impairment in older adults. Similarly, research from the University of California, San Francisco, found that frequent use of sleep medications was linked to increased risk of dementia among white participants.

Both studies were limited by the possibility that people with dementia pathology could use sleep aids for their sleep issues before they exhibit any signs of cognitive impairment. Meanwhile, a study from Denmark did not find any association between use of Z-drugs and subsequent dementia. 

But these studies have only correlational data; they cannot prove cause and effect. Researchers often turn to animal studies to help advance our understanding of drug interactions.

A recent animal study at Mass General Brigham of Harvard Medical School found that zolpidem restored sleep and reduced amyloid in a mouse model at early stages of Alzheimer’s disease. It’s not yet known whether the same effects occur in people.

Ksenia Kastanenka, PhD, who researches Alzheimer’s and was involved in the study, said these results suggested that sleep aids like Ambien “could be effective at preventing or slowing Alzheimer’s progression if administered at early stages of Alzheimer’s disease.”

But to validate the theory, “we need to see a number of clinical trials testing this idea in individuals that are predisposed for Alzheimer’s disease, that have sleep impairments,” Kastanenka said. 

Further research is needed on the correlation between Ambien use and dementia onset. Research also suggests that high doses of Z-drugs are associated with increased risk of falls, fractures, and strokes among people already living with dementia. 

Similar risks are found among older patients using zolpidem. The American Geriatric Society recommends clinicians avoid their use because of the increased risk of delirium, fractures, and hospitalizations. 

The benefits of a good night’s sleep

Uninterrupted sleep is crucial for brain health because the brain must progress through the sleep stages in an “orderly fashion” and cycle repeatedly through the night, said Dr. Rhonna Shatz, medical director of the UC Health Memory Disorders Center at the University of Cincinnati.

Each stage of sleep contributes to a different type of memory consolidation. Memory consolidation occurs when unstable traces of memory from the hippocampus, the deep brain region responsible for memory processing, are transferred to the cortex to help strengthen and form long-term memories.

The other important role of sleep is toxin clearance. The glymphatic system flushes toxic proteins and debris that build up from the day with spinal fluid. “Like an ocean tide coming,” Shatz said. 

An example of this is the protein amyloid, which contributes to Alzheimer’s disease risk. “Sleep is important for the process of helping to prevent the changes that ultimately lead to cognitive impairment,” she said.

It may be tempting, then, to turn to sleep aids for insomnia issues. But careful considerations should be made regarding drugs such as Ambien.

Can sleep aids mask a deeper issue?

“The fundamental issue is, why are you needing a sleep aid?” said Shatz. “The real problem is that there might be a primary sleep disorder.”

Physicians should test patients for sleep disorders and address sleep hygiene, she said. The reliance on sleep aids often means that patients are on the medication longer than recommended.

Experts say treatment should begin by identifying the cause of insomnia rather than relying on medication alone, such as limiting screen time before bed, avoiding caffeine, and keeping to a sleep schedule. Specialized forms of cognitive behavioral therapy sessions can also help with long-term insomnia.

Newer prescription insomnia medications, such as Dual Orexin Receptor Antagonists (DORA), are showing promising results. These include lemborexant, daridorexant, and suvorexant.  “These actually promote more normal sleep and potentially have some neurological benefits,” including supporting the glymphatic system to reduce amyloid buildup, Shatz said, 

For now, the evidence does not show that Ambien causes dementia. But because the research is mixed — and because the medication carries other risks for older adults — experts recommend using it only when appropriate, for the shortest possible time, while addressing the underlying causes of insomnia whenever possible.

Sleep has “been conserved across evolutionary time and across every species,” said Shatz. “It’s important that we respect it.”

Brooke Witherow is a freelance science and health journalist. A graduate of Columbia University School of Journalism, she also holds bachelors’ in neuroscience and sociology from SUNY Geneseo.