Someone drove to a store, bought whipped cream, and had absolutely no memory of it the next morning. The store’s security footage confirmed the trip. They had taken Ambien before bed.
That story isn’t an urban legend. It’s one of many documented accounts of a phenomenon that has baffled patients, unnerved physicians, and eventually forced federal regulators to act. Ambien (zolpidem) is one of the most prescribed sleep medications in the United States, and for most people who take it, it does exactly what it promises: delivers sleep quickly and reliably. What the label doesn’t adequately prepare you for is the range of Ambien side effects that can emerge while the drug is technically working – when the brain is sedated enough to lose conscious awareness but still awake enough to drive, cook, make phone calls, and carry out entire behavioral sequences with no memory of any of it.
The drug has been in American medicine cabinets since 1992. For over three decades it has been handed to patients as a safer alternative to older sedatives, partly because it works differently from traditional benzodiazepines. What three decades of post-market data have made clear is that the drug’s risk profile is considerably more unusual than its original approval suggested.
The Drug That Turns People Into Sleepwalkers
On April 30, 2019, the FDA advised that rare but serious injuries had occurred with certain common prescription insomnia medicines because of sleep behaviors, including sleepwalking, sleep driving, and engaging in other activities while not fully awake – and that these complex sleep behaviors had also resulted in deaths.
These behaviors appear to be more common with zolpidem than with other prescription sleep medicines. The FDA’s review wasn’t triggered by a handful of anecdotes. The agency also added a contraindication, meaning individuals who have previously experienced complex sleep behaviors should not take Ambien or any z-drug and should inform their prescriber.
Complex sleep behaviors – such as sleepwalking, sleep driving, sleep cooking, and engaging in other activities while not fully awake – carry a risk of serious and potentially fatal injury to oneself or others. These behaviors can occur at therapeutic doses of zolpidem with or without another CNS (central nervous system) depressant or alcohol. They don’t require weeks of use to appear. The FDA noted they’re not limited to people who combine the drug with alcohol.
The FDA identified 66 documented cases over a 26-year period, across all three z-drugs, resulting in serious injuries and deaths. Among those cases, one documented case report published in the American Journal of Medicine involved a man who took 10 mg of zolpidem at bedtime, was witnessed by his son getting into his truck and backing it into a tree, then drove it back to its parking spot, went inside, and had no recollection of any of it the next morning.
The deaths reported in the FDA’s review included cases of carbon monoxide poisoning, drowning, fatal falls, hypothermia, and fatal motor vehicle collisions.
You Can Have a Whole Night You Don’t Remember
Even without the dramatic sleepwalking episodes, zolpidem affects memory in a way that’s distinct from ordinary sleep. The drug produces anterograde amnesia – the inability to form new memories during peak drug effect. This is documented in clinical trials, particularly at doses above 10 mg. In plain terms: anything that happens in the hours after you take Ambien may simply never get stored in your brain.
Activities documented in reported cases include driving, making or eating food, talking on the phone, and sexual activity – all carried out by people who had no idea they were doing them and no memory afterward. These behaviors can occur at therapeutic doses with or without alcohol.
In clinical trials under controlled conditions, the memory effects were measurable even at standard doses. A 51-year-old woman in one case study who had used zolpidem 10 mg nightly for several years began walking, eating, and engaging in other activities in her sleep within a few weeks of starting the drug. The amnesia isn’t a side effect that declares itself. The person simply wakes up with a gap in their night – or, in worse cases, wakes up somewhere they don’t recognize.
The Morning After Is Also a Problem
The effects of Ambien don’t necessarily stop when you open your eyes. The FDA approved label changes for zolpidem specifically because of the known risk of next-morning impairment, warning that patients who take the extended-release version should not drive or engage in activities requiring complete mental alertness the day after taking the drug, because zolpidem levels can remain high enough the next day to impair them.
After a standard 10 mg dose of immediate-release Ambien, researchers found that 15% of women and 3% of men still had zolpidem levels high enough to impair driving after a full eight hours of sleep. With the extended-release 12.5 mg dose, those numbers jumped to 33% of women and 25% of men. These figures are drawn from the same FDA safety communication that prompted the 2013 label change – the agency published blood-level data directly in its January 2013 Drug Safety Communication.
That sex difference prompted a significant regulatory change. Women appear more susceptible to this risk because they eliminate zolpidem from their bodies more slowly than men. In response, the FDA lowered the recommended starting dose to 5 mg for women taking immediate-release products and 6.25 mg for extended-release, compared to 5 – 10 mg and 6.25 – 12.5 mg respectively for men.
A study published in the Journal of Clinical Sleep Medicine found that bedtime doses of zolpidem 7.5 mg produce driving effects comparable to a blood alcohol concentration of 0.05% – the legal limit in many European countries, and enough to measurably impair reaction time and lane control. A driver behind the wheel the morning after a standard Ambien dose may feel completely alert while being impaired in ways they can’t detect.
The Fall Risk Nobody Warns Older Adults About
For people over 65, Ambien carries an additional physical danger that has nothing to do with sleepwalking. The 2023 American Geriatrics Society Beers Criteria places zolpidem on its list of high-risk medications for older adults, specifically because of fall and fracture risks. That designation carries weight: it signals that for this population, the drug’s risks are serious enough to warrant extreme caution or avoidance entirely.
A 2018 systematic review and meta-analysis published in Age and Ageing found a 63% increased fracture risk across nine of ten included studies on z-drugs including zolpidem. Falls in older adults aren’t a minor inconvenience – hip fractures are associated with significant mortality, especially in people over 75. A drug that causes residual sedation and muscle relaxation overnight, then leaves a person groggy and unsteady when they wake to use the bathroom at 3 a.m., creates exactly the conditions for that kind of fall.
This is also why cognitive behavioral therapy for insomnia (CBT-I) – a structured, non-medication approach – has become the first-line treatment recommended by the American Academy of Sleep Medicine. CBT-I addresses the root behavioral and cognitive patterns that perpetuate insomnia, rather than simply suppressing the symptom for one night.
The Brain Risk That Emerges Over Time
The strangest and most recent concern about long-term Ambien use involves cognition itself. A 2025 meta-analysis published in Molecular Neurobiology found that zolpidem consumption was associated with a 28% increased risk of Alzheimer’s disease and dementia across a large pool of studies. The analysis covered nearly 3 million patients and represented the most comprehensive examination of this question to date.
Observational studies have suggested that use of GABA-A receptor agonists – the class of drugs that includes zolpidem – especially at higher cumulative doses, comes with an increased risk of dementia. The proposed mechanism isn’t entirely settled, but researchers have pointed to zolpidem’s potential disruption of the brain’s waste-clearance process during deep sleep – the system that flushes out proteins associated with Alzheimer’s.
One meta-analysis estimated that 28% increase in Alzheimer’s risk, while a separate analysis – a 2020 systematic review published in Current Sleep Medicine Reports – found no such association, meaning the research is not conclusive. A recent meta-analysis concluded that prolonged use of GABAergic drugs is associated with an increased dementia risk, but causality has not been firmly established. The data suggests a signal worth discussing with your doctor, particularly for people who have been using the drug for years rather than weeks.
Approximately 50% of patients continue zolpidem use beyond 12 months despite the fact that Ambien is FDA-approved only for short-term treatment of insomnia. Physical dependence can develop after as few as four weeks of continuous use at prescribed doses, and stopping abruptly after extended use carries its own risks. Around 30 – 40% of long-term users experience significant withdrawal effects when discontinuing the medication, which can persist for weeks to months.
If you’re already concerned about medications and memory, 9 popular medications linked to dementia and memory loss covers a broader range of drugs – including some commonly used sleep aids – that carry cognitive risk flags.
Why Ambien Is a Controlled Substance
Ambien is classified as a Schedule IV controlled substance under federal law, indicating accepted medical use but a recognized risk for physical dependence. That classification puts it in the same category as Xanax and Valium – drugs most people understand carry addiction potential. Zolpidem’s reputation as a “milder” option than benzodiazepines has arguably made people less cautious about long-term use than they might otherwise be.
Some of the side effects of Ambien include nausea, slow breathing, sedation, confusion, muscle cramps, anxiety, and potential for addiction, alongside the more dramatic complex sleep behaviors. The drug was approved as a non-benzodiazepine hypnotic – chemically distinct from older sedatives – but its mechanism of action targets the same GABA receptors, producing effects that overlap with benzodiazepines in meaningful ways.
Read More: People With Sleep Problems May Experience Hidden Risks if They Are Taking Common Sleep Pill
What to Do Now
Ambien is a genuinely effective drug for acute, short-term insomnia. The FDA’s own label states that long-term use is not recommended and that treatment should be as short as possible – yet roughly half of patients who start it are still taking it a year later.
If you’ve been taking it for longer than a few weeks, the conversation worth having with your doctor isn’t whether to stop immediately, but how to taper safely – abrupt discontinuation after extended use can trigger rebound insomnia and withdrawal symptoms. Ask specifically about CBT-I as a transition strategy: it addresses the behavioral and cognitive patterns that keep insomnia alive in ways that any sleep medication, by definition, cannot.
If you take Ambien and live with other people, telling them about the complex sleep behavior risk is practical safety planning – a person experiencing a sleep-driving or sleepwalking episode has no awareness of it themselves. Someone else noticing unusual behavior at night is often the only way the problem gets identified. Anyone who has previously experienced complex sleep behaviors on any sleep medication should tell their prescriber before being prescribed Ambien again – the FDA now considers prior history of these behaviors a contraindication. And for women specifically: if you’re taking 10 mg of immediate-release zolpidem and driving in the morning, ask your doctor whether the current dose is still appropriate in light of the 2013 FDA guidance that lowered the recommended starting dose for women to 5 mg.
Disclaimer: The author is not a licensed medical professional. The information provided is for general informational and educational purposes only and is based on research from publicly available, reputable sources. It is not intended to constitute, and should not be relied upon as, medical advice, diagnosis, or treatment. Always consult a licensed physician or other qualified healthcare provider regarding any medical condition, symptoms, or medications. Do not disregard, avoid, or delay seeking professional medical advice or treatment because of information contained herein.
AI Disclaimer: This article was created with the assistance of AI tools and reviewed by a human editor.
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