Checked against the current FDA prescribing information and FDA safety communications. Revised October 2026. This is educational material, not a substitute for advice from the clinician who prescribes your medicine.
On April 30, 2019, the U.S. Food and Drug Administration did something it rarely does to a drug that had been on the market for more than 25 years. It added a boxed warning, the agency’s most serious label alert, to Ambien (zolpidem) and two related sleep drugs, eszopiclone (Lunesta) and zaleplon (Sonata). The reason was a pattern of people getting up in the night, doing things while not fully awake, and getting badly hurt. The FDA’s 2019 drug safety communication counted 66 such cases reported between 1992 and early 2018. Twenty of them ended in death.
Those cases are rare. Most people who take zolpidem notice nothing worse than a little grogginess. But the 2019 warning reframed how doctors and patients think about Ambien side effects. They aren’t just a list of symptoms. They follow the clock: some happen in the hours after you swallow the pill, some show up the next morning, and some emerge only after weeks or months of nightly use. This guide is organized the same way.
One basic fact first. Zolpidem is a Schedule IV controlled substance in the United States, which means federal law recognizes a potential for misuse and dependence. Refills are limited, and your prescriber is expected to check in regularly.
During the night: the hours after the pill
Zolpidem acts fast. It’s designed to be taken right as you get into bed, and its effects build within minutes. This window, from the moment you swallow the tablet until the drug wears down overnight, is when the most dramatic Ambien side effects happen.
Complex sleep behaviors
“Complex sleep behaviors” is the FDA’s term for doing activities while you are not fully awake. The label lists sleepwalking and sleep-driving, and patients have described making phone calls, cooking and eating food, and having sex with no memory of it the next day. The person may look awake to others. They often recall nothing.
The injuries in the FDA’s review read like a list of every way a half-conscious night can go wrong: falls that caused bleeding in the brain and broken hips and spines, burns, near-drowning, exposure to cold, carbon monoxide poisoning, accidental overdoses, gunshot wounds, fatal car crashes, and apparent suicides. Three details from that review surprised many clinicians:
- The events happened with or without alcohol or other sedating drugs.
- They occurred even at the lowest recommended doses.
- They could happen after a single dose, not only after long use.
Because of this, the current Ambien prescribing information says the drug should not be given to anyone who has had a complex sleep behavior after taking it. If it happens to you, stop taking zolpidem and call your prescriber right away. Don’t take the next night’s dose “to see if it happens again.”
Signs a household member might notice: food missing or cooked overnight, texts or emails you don’t remember sending, the car parked differently, or bruises with no explanation. Any of these is worth reporting to your doctor.
Memory gaps
Zolpidem can cause anterograde amnesia, meaning you can’t form new memories for a stretch of time after taking it. The label describes a study in which people taking 10 mg and 20 mg had trouble recalling, the next morning, information they had learned near the drug’s peak effect. This is why staying up after taking the pill is a bad idea. Conversations you have, emails you write, or decisions you make in that window may simply vanish.
Hallucinations and confusion
Some people see or hear things that aren’t there, typically around the time they are falling asleep or if they fight the drug and stay awake. In adult trials of 10 mg at bedtime, fewer than 1% reported hallucinations. The rate was higher in a study of children with ADHD-related insomnia, where 7% of those on zolpidem had hallucinations compared with none on placebo. Zolpidem is not approved for children for this and other reasons.
Falls, especially in older adults
A sedated brain and unsteady legs are a dangerous mix on the way to the bathroom at 3 a.m. The label reports that in clinical trials outside the U.S., 1.5% of patients had falls, and 93% of those who fell were 70 or older. A hip fracture in an older adult can be life-changing. If you or a parent takes zolpidem, clear walkways, use night lights, and keep a phone within reach of the bed.
Slowed breathing
On its own, at prescribed doses, zolpidem usually doesn’t depress breathing much in healthy people. The label does note lower oxygen levels in people with mild to moderate sleep apnea and urges caution in anyone with breathing problems. The risk climbs sharply when zolpidem is combined with alcohol, opioids, or other sedatives. Our article on Ambien and alcohol explains why that combination is so risky.
The next morning: when the drug hasn’t fully left
The second time window is the morning after. You wake up, feel more or less fine, and get in the car. But zolpidem levels in your blood may still be high enough to slow your reactions, and, crucially, you may not feel impaired.
What the FDA found in 2013
In January 2013, the FDA announced that new driving-simulation and lab data showed next-morning zolpidem levels could stay high enough to impair driving and other tasks needing alertness. Women were affected more, because their bodies clear zolpidem more slowly. As reported at the time, about 15% of women taking the 10 mg immediate-release tablet still had blood levels high enough to raise driving risk eight hours later, compared with about 3% of men. For the 12.5 mg extended-release version (Ambien CR), the figures were about 33% of women and 25% of men.
The FDA’s response was to lower the recommended starting doses for women: 5 mg for immediate-release zolpidem and 6.25 mg for Ambien CR. It asked prescribers to consider those lower doses for men, too. A follow-up FDA drug safety communication from May 2013 went further for the extended-release version, advising that people taking Ambien CR at either strength should not drive or do anything requiring full alertness the day after taking it. Our guide to Ambien dosage for men vs women explains the dosing differences in detail, and Ambien vs Ambien CR covers how the two formulations behave across the night.
Why a short night makes it worse
The label states that the risk of next-day impairment, including impaired driving, goes up if you take zolpidem with less than a full night of sleep remaining. The instructions say to take it only if you can stay in bed for at least seven to eight hours, and to wait at least eight hours before driving. The classic mistake is waking at 3 a.m., taking a pill to get back to sleep, and then driving at 7. That leaves far too little time.
Other morning-after effects
- A “hangover” feeling: heavy head, slow thinking, or feeling drugged
- Daytime drowsiness that may last into the afternoon
- Dizziness or unsteady walking, especially on first standing up
- Vision changes, which MedlinePlus lists among problems to report to your doctor
If any of these show up regularly, don’t simply push through. Your dose, timing, or medication choice may need adjusting, and only your prescriber should make that change.
Day-to-day common Ambien side effects
Beyond the headline risks, most Ambien side effects people report are ordinary and mild. The FDA label gives incidence figures from placebo-controlled trials. In short-term studies (up to 10 nights), only a few reactions were noticeably more common on zolpidem than on placebo. In longer studies (28 to 35 nights), the list grew a bit. The figures below come straight from the label.
| Side effect | Short-term trials (up to 10 nights): zolpidem vs placebo | Longer trials (28 to 35 nights): zolpidem vs placebo |
|---|---|---|
| Headache | 7% vs 6% | Not among the listed differences |
| Drowsiness | 2% vs 0% | 8% vs 5% |
| Dizziness | 1% vs 0% | 5% vs 1% |
| Diarrhea | 1% vs 0% | Not among the listed differences |
| “Drugged” feeling | Not listed | 3% vs 0% |
| Allergy symptoms | Not listed | 4% vs 1% |
| Sinus inflammation | Not listed | 4% vs 2% |
| Dry mouth | Not listed | 3% vs 1% |
| Lethargy | Not listed | 3% vs 1% |
| Back pain | Not listed | 3% vs 2% |
| Depression | Not listed | 2% vs 1% |
Two things stand out. First, the gap between zolpidem and placebo is small for most effects. Plenty of people in sugar-pill groups also report headaches and tiredness. Second, drowsiness and dizziness become more noticeable with weeks of use, which fits with the drug lingering in some people’s systems. MedlinePlus also lists nausea, constipation, unusual dreams, muscle aches, and unsteady walking among commonly reported effects.
Mood and mind
Sleep drugs work on the brain, so it’s no surprise that some side effects show up as changes in thinking and feeling. These are less common than drowsiness, but they matter more.
Worsening depression and suicidal thoughts
Insomnia and depression often travel together. The Ambien label warns that, in people with depression, sedative-hypnotics like zolpidem can make symptoms worse, and that suicidal thoughts and actions, including completed suicides, have been reported. For that reason, prescribers are asked to give the smallest practical supply to people with depression and to watch them closely.
If you or someone close to you has thoughts of self-harm, call or text 988 to reach the 988 Suicide & Crisis Lifeline, available 24 hours a day in the U.S. If someone is in immediate danger, call 911.
Abnormal thinking and behavior changes
The label also describes a range of unusual thinking and behavior with sedative-hypnotics. People may become less inhibited than usual, more aggressive, or act out of character. Others report agitation, confusion, or feeling detached from themselves. These changes can be hard to notice from the inside. A partner or family member is often the first to say, “You’re not acting like yourself.”
One important point from the label: because insomnia can itself be an early sign of a physical or psychiatric illness, new or worsening thinking and behavior problems need a careful medical look. If insomnia hasn’t improved after 7 to 10 days of treatment, the label says that suggests another illness may be present and should be evaluated.
Allergic and rare reactions
Severe allergic reactions to zolpidem are uncommon but can be dangerous. The label describes cases of angioedema, which is swelling of the tongue, throat, or voice box, and anaphylaxis, a whole-body allergic reaction. Some people have needed emergency treatment, and swelling of the airway can be fatal. Someone who has had angioedema with zolpidem should not take it again.
Call 911 or get emergency care for any of these after a dose:
- Swelling of the face, lips, tongue, or throat
- Trouble breathing or swallowing, or a tight throat
- Hives or widespread rash with dizziness or fainting
- Nausea and vomiting together with any of the above
MedlinePlus also lists other uncommon symptoms that warrant a prompt call to your doctor: yellowing of the skin or eyes, light-colored stools, chest pain, a pounding heartbeat, and vision problems.
Signs of taking too much
Overdose effects listed on the label range from deep sleepiness to coma, along with breathing and heart problems. The danger is much greater when zolpidem is combined with other sedating drugs or alcohol. If someone can’t be woken, is breathing slowly or irregularly, or has blue-tinged lips, call 911. For questions about an accidental extra dose in someone who is awake and alert, Poison Control is available at 1-800-222-1222.
Long-term use effects: weeks, months, years
The third time window is the long one. Zolpidem was approved for short-term treatment of insomnia marked by trouble falling asleep. In real life, many people take it nightly for months or years. That’s where a different set of side effects comes in.
Tolerance
Some people find that, over time, the same dose doesn’t seem to work as well as it did at first. The temptation is to take a second pill. Don’t. The label sets a firm ceiling of 10 mg a day for immediate-release zolpidem, and higher doses raise the risk of every side effect described above, including complex sleep behaviors and next-day impairment. If your usual dose has stopped helping, that’s a conversation for your prescriber.
Dependence
Physical dependence means the body has adapted to the drug and reacts when it’s suddenly removed. Psychological dependence means feeling unable to sleep, or even try to sleep, without the pill. Both can develop with zolpidem, which is part of why it’s a controlled substance. MedlinePlus states directly that the drug may be habit-forming, and advises against taking more, taking it more often, or taking it longer than prescribed. The risk is higher in people with a past history of alcohol or drug misuse.
Rebound insomnia and withdrawal
When zolpidem is stopped, sleep may be worse for a night or two. MedlinePlus notes this is common and usually fades quickly. After longer, heavier use, stopping suddenly can cause true withdrawal. The label lists symptoms ranging from low mood and insomnia to stomach cramps, vomiting, sweating, shakiness, and, rarely, seizures or delirium. That’s why any plan to cut down or stop should be built with your prescriber, who can design a gradual taper that fits your situation. Our article on Ambien withdrawal describes what that process can look like and what symptoms to watch for.
Who’s at higher risk of Ambien side effects
Side effects aren’t spread evenly. Certain groups are more likely to have problems, and doctors adjust their approach for them.
Adults 65 and older
Older bodies clear zolpidem more slowly, and older brains are more sensitive to sedation. The label recommends 5 mg as the dose for elderly patients. The American Geriatrics Society’s Beers Criteria, the widely used list of medicines that are often inappropriate for older adults, goes further. Its 2023 update says the “Z-drugs,” including zolpidem, should generally be avoided in older adults because of links to falls, fractures, delirium, cognitive problems, and car crashes. This doesn’t mean no older adult can ever take it, but it raises the bar.
Women
As covered above, women clear zolpidem more slowly than men and reach higher blood levels on the same dose. That is the reason the recommended starting dose for women is half the old standard.
People with liver disease
The liver breaks down zolpidem. With mild to moderate liver impairment, the label recommends a 5 mg dose. People with severe liver impairment should avoid it, because it may contribute to a type of brain dysfunction called hepatic encephalopathy.
People with sleep apnea or lung disease
Sedatives can relax the airway and dull the brain’s drive to breathe. If you snore loudly, stop breathing in your sleep, or have COPD or another lung condition, make sure your prescriber knows. Untreated sleep apnea is also a common hidden cause of poor sleep that a pill won’t fix.
People taking other sedating drugs
Opioid pain medicines, benzodiazepines, some antidepressants, muscle relaxants, allergy medicines with sedating antihistamines, and alcohol all stack with zolpidem’s effect. If you’ve ever compared sleep medicines, our articles on Ambien vs Restoril and Restoril vs Lunesta explain how the different drug classes compare.
Reducing your risk: a bedtime checklist
Most serious Ambien problems come down to timing, combination, and setting. A few habits cut the risk a great deal. Run through this list each night you take it:
- Do you have a full 7 to 8 hours? If not, skip the dose. Never take it in the middle of the night unless your prescriber has given you a product and instructions specifically for that.
- Have you had any alcohol tonight? The medication guide says not to take Ambien if you drank alcohol that evening or before bed.
- Are you already in bed? Take it immediately before lying down, not while you are still finishing chores or watching TV on the couch.
- Did you eat a big meal recently? Taking it with or right after a meal can slow how fast it works, which may tempt you to stay up.
- Are you taking only your prescribed dose? No second tablet, no doubling up because last night was rough.
- Are other sedatives in the picture? Check with your pharmacist about any new medicine, including over-the-counter sleep aids and cold remedies.
- Is the house safe? Car keys put away, stove off, clear path to the bathroom, night light on.
- Does someone know? Let a partner or housemate know you take zolpidem so they can recognize unusual nighttime behavior.
And in the morning: don’t drive or do anything risky if you feel at all drowsy, and remember that you can be impaired even when you feel fine. Long term, ask your prescriber about cognitive behavioral therapy for insomnia (CBT-I), which major medical groups recommend as the first-line treatment for chronic insomnia and which doesn’t carry any of these drug risks.
Frequently asked questions
What are the most common side effects of Ambien?
In FDA label data, the most common effects compared with placebo were drowsiness, dizziness, headache, and diarrhea in short-term use, and drowsiness, dizziness, a “drugged” feeling, and allergy-like or sinus symptoms with longer use. Most are mild.
Can Ambien make you do things you don’t remember?
Yes. Sleepwalking, sleep-driving, eating, and making calls while not fully awake have been reported, often with no memory afterward. This is the reason for the 2019 boxed warning. If it happens, stop taking zolpidem and contact your prescriber.
How long do Ambien side effects last the next day?
It varies by dose, formulation, sex, age, and liver function. Many people feel clear by morning, but impairment can persist without obvious symptoms. The label advises waiting at least eight hours after a dose before driving, and the FDA says people taking Ambien CR should not drive the next day.
Is Ambien addictive?
Zolpidem is a Schedule IV controlled substance because it can cause misuse and dependence, especially with long-term use, higher doses, or a history of substance use problems. Stopping suddenly after long use can cause withdrawal, so any change should be planned with your prescriber.
Are Ambien side effects worse for older adults?
Generally, yes. Older adults have higher rates of falls, confusion, and next-day drowsiness on zolpidem. The label recommends a 5 mg dose for elderly patients, and the Beers Criteria advise generally avoiding Z-drugs in this age group.
