Why Do Some Insomniacs Keep Waking Up At the Same Time?

One of the most common complaints that I get from patients is that they keep waking up at the same time in the middle of the night and are unable to get back to sleep, or they keep waking up every 90 to 120 minutes. This phenomenon is called sleep maintenance insomnia, when you are unable to stay asleep during the night. In contrast, sleep onset insomnia is when you’re unable to fall asleep in the beginning of the night.

A low-dose version of zolpidem (Ambien) was recently FDA approved as Intermezzo to treat these middle of the night awakenings. It’s purpose is similar to zaleplon (Sonata), which is a very short-acting sleep aid, so it can be used in the middle of the night to get back to sleep, without the “hangover” effects that people feel with typical sleep aids.

There are a number of different explanations for why some people keep waking up in the middle of the night. One theory is that people with insomnia are hyperarousable, with higher levels of brain activity and stress hormones. If it’s due to these factors, why is it that insomniacs keep waking up at the same time? One possible explanation is that it has to do with sleep stages. Humans go through 4-5 cycles of sleep, where deep sleep (slow wave) predominates in the first half of the night and REM sleep is more common in the second half. As the night progresses, the periods of REM sleep become longer and longer. Since we know that throat muscles are most relaxed during REM sleep, you’re more likely to have breathing pauses during REM, especially if you’re anatomically predisposed (narrowed upper airway anatomy).

This can explain why many people say that they keep waking up at 3AM, like clockwork. Some people wake up when REM length reaches a critical period, whereas other keep waking up with each successive REM period. Transitions into and out of REM can also predispose one to upper airway instability.

One thing I’ve noticed is that in almost all cases, severe insomniacs have very narrowed upper air passageways. On endoscopy, the space behind the tongue is very narrow, and most people can’t (or prefer not to) sleep on their backs, since the tongue is more likely to fall back then supine. Dr. Barry Krakow did a study a while back showing that the vast majority of insomniacs who were resistant to sleeping pills had sleep-breathing problems.

What I’m describing is not necessarily obstructive sleep apnea. Once you obstruct or have partial obstruction, you can either continue the breathing pause for 10 to 40 seconds (this is called an apnea or hypopnea). But if you wake up quickly within a few seconds, then it’s called an arousal. Insomniacs typically have lots of arousals.

This is why even if you have classic insomnia, you need to look for and treat any underlying sleep-breathing problems, regardless of whether or not you have apneas.

If you are an insomniac, what time do you wake up in the middle of the night?

Please note: I reserve the right to delete comments that are offensive or off-topic.

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.

95 thoughts on “Why Do Some Insomniacs Keep Waking Up At the Same Time?

  1. After I was intubated, after an accident, I started to have trouble with insomnia. In the beginning I’d wake up every 15minutes, now its been consistently every 90 minutes and I can barely remember that I dream. The headaches it caused were the worst. I now use a CPAC mask and t hasn’t changed. Now the worst I get is that I have ear pain and throat pain from being dried out’by the CPAC. The Drs say its due to sleep apnea, as I used snore, but I feel since I had injury to my spinal cord, that the reticular system fails. I used to get this buzzing in my back below my neck, but after the injury to my spine, it stopped and that’s when I faced I no longer could sleep.now when I’m awake I get this buzzing in my head ad irregular/heart beats. I don’t feel I panic until I get this buzzing and/crackling noise in my brain…can’t tell if its my brain or my/ears.But i noticed it less when I’m walking or working, as if its dye to a circulation orobkeb, but upon sleep and/relaxation it starts up again. Between not sleeping and the sounds implement hearing I find it very hard to think.and ts getting to me….its been getting worst I fear….as I’m sleeping less and less during the night and falling asked during the/day. My Dr suggest seeing a shrjnk, but I feel they screwed up my brain in the first place. What’s a person to do.,..pray? It doesn’t help me anymore!

  2. Hi Dr Park, Do you have any strategies to fall back asleep after being woken up in the middle of the night? I live next to loud noises that occur late at night which are unavoidable, even with ear plugs, that is the reason for my wakenings. Please any strategies to help get back to sleep are greatly appreciated.

  3. John,

    Unfortunately, the best answer is to move to a less noisy home. However, obstructed breathing can cause you to say longer in light sleep, making you more susceptible to noises. If you have any of the features that I mention, it’s probably worthwhile getting checked for obstructive sleep apnea.

  4. Hi dr.steven parker.

    For a month and a half now I’ve been unable to sleep consistently through the night.I sleep fine if I sleep 6 pm, but if I try to sleep any time earlier, i always end up with 4 hours sleep, no matter what I do. It all began after i had a period of anxiety and stress. So I stayed up all night during that period, sometimes until the morning, just so i don’t get into the pattern of anxious thinking. The anxiety and stress went away. But i’ve been unable to sleep at normal times. If I try to sleep at normal times, i get fragmented sleep and wake up after 4 hours. The time when i sleep normally is usually 6 PM. I usually wake up during dreams, i’m almost always waking up during dreams.

  5. Hello I’m 17 year old male looking for an answer to these questions that keeps plaguing me why can’t I stay asleep and why do I feel uneasiness/worry all day long. I haven’t told my mom but I can’t sleep till around 3 then I’ll sleep for around 3-4 hours till 6-7 then weird things happen I’ll awake kind of panicky but I’ll calm myself down to the point where I get drowsy again but I nod of into a wild fancy weird dream involving stresses like running from something and feels like I’m dreaming enough to last a whole night but then I’ll wake up and it’s only been 40-60 minutes. I generally feel tired and depressed throughout the day can’t take naps but my question is why do I feel nervous/depressed but not at anything at particular all day long. Appetite is normal and I exercise everyday I just worried I have some problem

  6. I have been waking up every am around 5am for the past 4 months. I am on Trileptal, Ativan, Remeron, Geodon, and Vistaril. I am getting about 6 hrs sleep. If I take 1mg of Ativan I may go back to sleep but be down all day.
    The stress moving last year and divorce, plus my sister’s suicide attempt and my 84 year old mom letting her move in is the major stressors.. Is there something I can take at 5am to get back to sleep until 8 or 9

  7. Thanks- I forgot to mention that I have had fibromyalgia since 2008 and adrenal fatigue. I go to a naturopath and a psychiatrist.. He does not get it that I don’t get enough sleep and it causes depression to be worse

  8. For the past 5 months I’ve been waking up in the middle of the night at 3-4AM and I wouldn’t be able to get my sleep back until maybe half and hour or an hour at most, it’s been bothering me a lot and I have no idea how to deal with this since I have insomnia.

  9. Im 13 and for the past couple nights I havnt been able to sleep properly I wake up at 2:30 every night and it creeps me out cuz 3:00 is witching hour. After 2:30 it takes me ages to get back to sleep only to be awaken at 5:50. I then try to go back to sleep and usually succeed this has been going on for 3 nights now. I have told my friend and he seems to think I have insomnia however I dont want to label myself incase he is wrong. Im scared incase this continues in to the school year and I cant concentrate in class. I haven’t told my parents yet. Does anyone know what I have? Is it insomnia?

  10. Hi,
    I need help, really.
    I have anxiety from previous substance abuse to deal with the depression of family crisis. I am under a new prescription of depressants only 50mg but they are ment to make me sleepy but I’ve been waking up every night, from falling asleep at 9 I’ll wake up at 2am and not get back to sleep until 7am it’s happened the last week. I have been drug free for a month. It’s my second night in a refuge, I was made homeless by my mother whom has a mental illness which adds to my stress level and recently secured s job that I am stressed about my mind won’t let me get back to sleep once I wake up I’m up. I just need some advice as I start university again in a week and really need to fix this or I’m afraid I’ll be unable to cope I love my sleep. I lay tossing and turning and no matter how tired I feel I don’t get to sleep for 4 hours atleast

    If anyone could help thank you I would appreciate it so much

  11. Dr.Park,

    Thanks for the information.

    I wake up often during the night, sometimes more than twenty times that I notice and always during REM. I have videotaped my sleep many times and when I wake up it never appears that I have stopped breathing. I don’t snore, gasp or in any way appear to be trying to get breath though many times I am scratching my face or rubbing my eyes just before I appear to awaken. I am resistant to sleep medications except that occasionally diphenhydramine will help.

    I have had a sleep study and the doctor said I had mild to moderate sleep apnea. I was certain that I would not be compliant with a APAP/CPAP or mouth guard. I tried the Provent therapy and it didn’t help and I often just tore them off during the night without even being aware of doing so. I also got a tonsillectomy and uvulectomy, which didn’t help.

    I have been a bit dubious about the apnea diagnosis. My doctor is very new to sleep disorders and what research I have done has indicated that an apnea is at least 10 seconds of non-breathing but my own sleep monitoring did not show that. Yes, the sleep study did indicate a drop in blood oxygen but I thought that the study was not a good indication of how I normally sleep.

    Now that I have read your article, it seems that you are saying that even a few seconds of non-breathing, which I don’t think I would have been able to detect in my monitoring, can lead to an arousal. Am I understanding correctly?

    You also seem to be saying that this is not necessarily OSA. Are you saying that because OSA is defined by more than 10 seconds of non-breathing so less than that can lead to arousal but may also be caused by breathing problems due to obstruction? And if so, is a CPAP/APAP machine the best or only therapy other than what I have already tried?

    Thanks in advance for any response.

  12. Chris,

    Yes and yes to your questions. Please search for and read my articles about upper airway resistance syndrome.You can have significant oxygen desaturations even with less than 10 seconds pauses. I see it all the time during sleep endoscopy.

  13. Chris,

    Please take a look at my articles on upper airway resistance syndrome (UARS), which will explain in much more detail what I”m talking about. Home/consumer monitoring and even most in-lab sleep studies are not designed to measure these subtle arousals. The best way to to place a pressure sensor in your esophagus, but this is not practical for most people. I recommend you start with the conservative steps I outline in my various articles, make sure you’re breathing well though your nose, then try dental options, including mandibular advancement devices and orthodontics. It’s best to be evaluated by an ENT specialist who can look at your airway with a camera when you’re lying flat on your back. Good luck.

  14. Hello Dr. Park!

    I wish you were closer to me, I would go see you. I am on bioidentical HRT and take Progesterone 150 mg capsule at bedtime. I have no problem falling asleep but I wake up several times between about 1230 am and 430 Am. I have noticed that it seems to be right after a dream. I recently had a home and lab sleep study and they told me that it was all normal. I insisted that I am looking for help for insomnia and they offered to monitor me with actigraphy for two weeks. I do not understand why because I know what is happening to me as far as waking goes. I am frustrated. I follow good sleep hygiene and I exercise regularly. Here are my sleep study results:

    Sleep Continuity and Sleep Architecture
    Total recording time (TRT) was 495 minutes, and total sleep time (TST) was
    454 minutes, for a sleep efficiency of 92%. Total sleep time was within
    expected limits. Sleep onset latency was decreased compared to expected
    limits. Sleep was fragmented by arousals due to respiratory events, arousals
    due to periodic limb movements and idiopathic arousals. The arousal index was
    10, which was not significantly elevated. The amount of Stage 1 (light) sleep
    was decreased. The amount of slow wave sleep was within expected limits. The
    amount of REM sleep was within expected limits. Latency to REM sleep was

    Respiratory Measures
    Respiratory monitoring did not show significant sleep disordered breathing
    sufficient to disturb sleep. Oxyhemoglobin saturation remained greater than
    89% at throughout this study.

    EKG demonstrated sinus rhythm throughout.

    Periodic Limb Movements
    Periodic limb move
    ments occurred frequently but did not cause significant
    sleep fragmentation. The periodic limb movement index was 13. The periodic
    limb movement index with arousal was 1.

    With the limited montage recorded, no EEG abnormalities were observed.

    Behavioral Abnormalities
    No significant behavioral abnormalities were observed during this study.

    What do you think?


  15. lf you people don,t have any medical problems like sleep apnea or trouble breathing
    or anything else l recomend you to walk or stand in your living room for 1/2 an hour before you go to bed and when you go to bed meditate try to concentrate in your breathing only until you fall sleep this might help you sleep better and if you wake up in the midle of the night go to bed at 12 midnight and you may wake up around 5 a.m.
    l suffer from imsomnia for more than 30 years and l take sleeping pills but still my brain wake me up after 4 hours of sleep and surprise why doctors have never investigate why our brains do this and all they do is just give you sleeping pills that most of the time help you just a litle bid ,l just read an article about a doctor that was investigating about this in rats and concluded that the brain is the one that wake us l knew this all my life hoefully he said that he is going to keep investigating this problem l slao don’t understand why scientis have not investigate the african fly “sept-sept ” that can make you sleep for along long time
    they could have better sleeping pills.

  16. Maureen,

    Thanks for your comment. I can’t say without examining you in person, but it’s not surprising that you’re waking after after dreaming, since that’s when your throat muscles are most relaxed. Assuming the airway is very narrow, I generally recommend trying the standard options for obstructive sleep apnea, starting with nasal breathing optimization and trying devices like a mandibular advancement device,or even CPAP. Staying off the back is also generally recommended, but you’re probably already doing that, right?

  17. No matter how tired I feel, Once i go to bed I fall asleep immediately then wake up for no apparent reason at 4:30 am every day and I’m not able to go back to sleep again (and I don’t even feel tired) . It’s really annoying that it keeps on happening over and over.
    I only manage to fall asleep again around 12 pm but when I wake up , I’m as exhausted as ever.
    I don’t know what to do, it affects my ability to concentrate in my classes.

  18. Ok. I will speak what I have to say.. I wake up at the same time every morning no matter what time I fall asleep.. it has become normal… past 2night I have woke up at 3:06… it is usually at 3:00.. Crazy thing is also I hear things not during that time when I wake up but when I go threw the day..

  19. Good morning,

    I am bi-polar and take Seroquel and bromazepam to sleep at least 475 gms of Seroquel. Every nite I go to bed at 11pm and am up every night at exactly 1pm.

    Please help!-I also have very disturbing dreams about people I knew in my past life!


  20. I often do the 2am wake up thing, while falling asleep within a minute or two when I initially go to bed at night.

    One thing that works for me is a derivative of “counting sheep.” I choose some sort of travel or trip thing that I’ve done many times — or had great significance to me — and I will retrace the route in vivid detail. Within a short time I can’t follow the process any longer and I fall asleep.

    For instance I did a marathon about 7 years ago. I will go mile-by-mile how the race went, remembering the start line, how the road dipped down, how it was passing by the zoo, where I got a rock in my shoe and had to stop for a second, etc etc. I almost never make it to mile 6 and have never made it more than half way!

    I’ve also used long car trips that are familiar, mountain bike rides and even exciting blow-by-blow highlights of professional sports games I’ve watched.

    I think what’s going on is that I’m flooding my brain with relatively positive memories so the worries, anxieties of the day don’t creep in helping me relax and fall asleep.

    Hope this helps!

  21. I have had insomnia for several years now period Ambien does not work at all for me. I wake up every hour on the hour like clockwork. nothing seems to help, and my insurance will not pay for a sleep study. any suggestions on what I can take to help me fall asleep or stay asleep I mean. I fall asleep easily during the daytime but never sleep for very long. The easy arousal seems very common for me I have always been a very light sleeper any little noise will wake me up before my hour is up LOL. I am considering taking something as heavy as Seroquel just to knock me out. But that’s probably not healthy for the rest of my body? Any suggestions… Thank you, Sarah.

  22. I wake up every morning for the past 2-3 months between 3 & 5 a/m. I cannot get back to sleep. I am supposed to use a bipap machine due to supposedly severe sleep apnea, but I have not been using machine. I somehow have stopped, I forget to turn it on or fall asleep w/out it. I sleep well w/out it. I cannot get back to sleep. I am an insomniac, I take meds for sleep that work. It is easy for me to fall back to sleep with my morning meds, and sleep better in the early a/m. I do not understand this. I have been through 12 surgeries since 2009, and the pain sometimes wakes me as well, but not often.If I do not get back to sleep in the a/m, I do not function during the day. In fact, I do not function until my afternoon meds at 2 p/m. I am losing my memory. I am stressed and overwhelmed and have trouble making decisions. I just turned 60 and have always lived alone since I left home at 19. Thank you

  23. Hi…I am a 46yr old female..a medical doctor myself.Having a BMI of 19 and physically very active.
    I have noticed that I have a problem of waking up at 3 am almost daily.
    By 4.30am I am wide awake.
    Also I do not feel tired or sleepy at all.

    I have been getting only 4 hours sleep at night cos I can’t fall asleep earlier.
    Upon waking I hit exercise right away and do a work out of 90 min which is inclusive or cardio,weight and yoga/pilates.Totally able to train at high intensity with only 4 hours of sleep.

    But even though I do not feel fatigue or tired I still do not feel rested either.Its like my mind is constantly at work and cant shut down.

    I do not use smartphones at nite cos I do not want visual or audio stimulation.
    Diet wise..I do not take coffee or tea..eat mainly organic food . I am a vegetarian and have normal serum Iron levels too.

    At the back of my mind I feel that I would like to have at least 7 hrs of sleep and not too happy that my body knows no fatigue.
    I cant even feel sleepy for a nap!
    Mental alertness is normal but yet I feel I wish I could just feel more rested.

    My body seems to be in overactive mode..I feel my attention span is shorter these days…can get very talkative on some days and keep on cleaning the house when back from work.

    I would really like to know how I could get some deep rest.

    These 4 hours sleep I have is sans dreams.

    Previously when I used to sleep 7 hrs a day last year..I would be constantly dreaming but not now..4 hours if almost dreamless.

    But I feel a tight sensation at the center of my forehead which makes me massage my head on and off.

    Just need to know what can be done?

  24. Hi Dr Park,

    I’ve been suffering from some form of insomnia since i was 13 years old.
    This used to always be trouble falling asleep, but i could make up for that by sleeping til later.
    However, the past years waking up at either 1-3 AM or if i’m extremely lucky 5 AM has become a big problem.
    I did in the meantime fix my problems of falling asleep by having a disciplined eveningtime and avoiding blue light.

    I’ve done testing for insomnia at http://www.geldersevallei.nl/ and they said things were fine.
    Apart from early melatonin production which using blue light before sleep was supposed to fix.

    Other than that i do often tend to have one nasal hole that i can’t really breathe through.
    My girlfriend says that i snore during sleep.

    The effects of this only really sleeping half of the night are low energy, trouble concentrating and remembering stuff.
    But also moodiness especially during the morning.

    So i was wondering if you might know any way that it would be possible to actually sleep through the second half of the night.
    And obviously actually not feel a lot more tired when i wake up, compared to when i went to bed.

  25. Bart,

    Thanks for commenting. Nasal congestion and snoring raises suspicion for possible obstructive sleep apnea. As I mentioned in the article, around 3 AM is when people go into long periods of REM sleep, when you stop breathing more often. Usually, I order a sleep test in these situations. Good luck.

  26. Dear Dr Park,

    Thanks for response but is it possible to have obstructive sleep apnea if one does not snore or have nasal congestion?
    Like today I woke up at 4.30am..but pretty fresh so I got up and started my daily routine.

  27. I sleep in 3-4hr cycles.. and then I am awake for 2-3hrs.. I have tried melatonin.. and silentor… and natural oils.. melatonin gave me leg twitches.. silector worked for about a week

  28. My mom passed away 2 years ago and in that past 2 years I haven’t been able to stay asleep. My sleep cycle constantly has been changing but it has never changed to where I can stay asleep through the middle of the night. I used to wake up every night at 3 in the morning then sometimes I would wake up after 2 hours and couldn’t fall back to sleep for hours. I have tried going to sleep earlier before but it only causes me to wake up more it seems. It’s like I don’t sleep I just take naps throughout the night is there anything I could do to stop this from messing with my daily activities because of drowsiness and not getting up on time when needed.

  29. I typically wake up after 4 hours of sleep. If I’ve had a particularly exhausting day, I’ll fall right back to sleep. Other times (like now), I can be awake for even a couple of hours. I think I need to keep my phone in another room. But 4 hour intervals are common with me.

  30. This rings true for me. I almost always wake up with a start exactly an hour after first falling asleep. I am asthmatic, although my asthma is very well-controlled by medication and I haven’t had a full-blown attack in many, many years. Most nights I have a nightmare that my airway is blocked by a foreign object – I then wake up, occasionally in a state of some distress. I occasionally wake up on my knees with my fingers down my throat, which is absolutely terrifying. I can usually go back to sleep after about 5-10 minutes and sleep through until morning.

    I’m healthy and active otherwise and not sleepy during the day. I used to be overweight but I have lost 50lbs in the last two years and am now at a normal weight. I’m 46 years old and I don’t drink or smoke. I always sleep on my side – the problem is far worse I sleep on my back. I don’t believe I have sleep apnea – I wear a Fitbit to monitor my sleep patterns and I only wake up that one time, after my first dream of the night. I wish I could make it stop. I’ve recently started taking melatonin and I think it’s helping a little – I still wake up but without all the dramatics. It’s hard to know if my problem is mental, physical or a bit of both!

  31. Hi, no matter what time i roll over and go to sleep, (i always prefer my right side, for some reason), i always wake up again almost exactly 90 minutes later. i then go straight back off to sleep with no further problems. it’s as though i do not go into a deep sleep and my body clock tells me to wake. it does not actually cause me problems but i would prefer to have a full good nights sleep. any ideas ?

  32. Mr. Houston,

    What you’re describing is only a problem if it causes issues during the day. 90 minutes is one sleep cycle, when you go from light to deep sleep. If you reach REM sleep, you’re more likely to have breathing problems due to muscle relaxation, and you’ll wake up. The fact that you prefer to sleep on your side supports this possibility, as people with more narrow airways prefer not to sleep on their backs. I talk about ways to improve sleep in my other blog articles (such as not eating late, optimizing your nasal breathing, etc.).

  33. Jo,

    Thanks for sharing. What you describe is consistent with what I’m describing in the article. Unfortunately, there is no way to confirm or deny you have sleep apnea without undergoing a sleep test. Home smartphone apps or bed partners are very poor at predicting sleep apnea. You can be thin, female, not snore and have a thin neck, and still have significant obstructive sleep apnea. Even if you don’t have sleep apnea on a test, you can still stop breathing multiple times every hour and keep waking up, especially when you’re in REM sleep, when your muscles are most relaxed. This is called upper airway resistance syndrome. What you’re dreaming may actually be true.

  34. I wake up sometimes every hour. I have tried melatonin, unisom, herbal things, benedryl, and was not working, and I was getting increasingly agitated. I also have dreams I am choking and do not sleep on my back. I was prescribed 5 mg ambien and tried it last night and slept about 4 hours and then woke up at 2 something, 3 something, 4 something, and then 5, and went back to sleep.

  35. I wake up every 90 minutes every-night and have been doing this since 2003. I’m exhausted because I feel like I never get any restorative sleep. Yes I do have sleep apnea, and I use BiPap with no problems. I no longer have any apnea events. I have tried herbal remedies and such but nothing will allow me to sleep threw the night, or even more than 2 hours max. I do fall right back to sleep after I get up and use the restroom.

  36. Sally,

    One possible reason why people still wake up every 90 to 120 minutes despite CPAP is that you enter REM sleep every 90 to 120 minutes. This is when throat muscles are most relaxed and most prone to obstructed breathing, even with CPAP. Pressure needs may change with time, so it’s important to check the settings regularly with your sleep doctor.

  37. I typically sleep 5 to 6 hours depending if I have been sleep deprived. If I went to bed every night at 12am for few months I would wake up at 532 am. My whole life I have never slept long. The older I get I notice breathing problems maybe efecting my sleep. I get asma when I’m sick. I live in the mountains in Colorado and just recently moved to Oregon. When I go back and forth I notice when I’m trying to sleep at 10,000 feet and I haven’t been aclimatized or sick I hold my breath and catch my self before I can fall asleep and I feel like I was dream of drowning.

  38. I do not sleep well in a sleep lab. I have gone from a Cpap to an Bipap machine.
    My AHI is still all over the place. From 30 to 10 on any given night.
    I do wake up around 3 or 4 am every night. I then struggle to sleep another 2 to 3 hours. I feel very sluggish in the morning. Most sleeping pills and even gabapentin make me feel medicated in the morning. Not sure what to do next.