Medical Cautions


Numerous sleep-related medical conditions can make it significantly harder to adapt to polyphasic schedules and it may be not advisable to attempt adaptation for some of the conditions listed below. While this article may provide general information and recommendations, it does not provide a medical advice and it is advisable you consult with an appropriate medical professional if you have any doubts about adaptation or health conditions.


If you are suffering from narcolepsy, you should take caution in considering a polyphasic sleeping schedule. Consulting your doctor is very advisable in this case. Do not attempt a polyphasic sleep schedule on medications like Xyrem or Modafinil. Modafinil is a medicine usually prescribed to people suffering from narcolepsy or hypersomnia.  Consumption of Modafinil while on polyphasic sleeping is not recommended due to extremely long half life (15 hours) which means it is likely to impact the quality of multiple successive sleep sessions. Xyrem is used to treat sudden muscle weakness and excessive daytime sleepiness. It has a short half life (around 1 hour). Napping after consuming  this drug is very hard.

If you notice yourself unable to stay awake during more tasks than before, do not continue with polyphasic sleep! This is very dangerous. Narcoleptics suffer from excessive amounts of REM, reduced SWS and possibly frequent sleep interruptions. Constant tiredness and attacks of falling asleep which are hard to control during the day can be a dreadful combination for doing a polyphasic sleeping schedule. Cataplexy severity and frequency, however, does not have an effect on your sleep and the specific sleep needs!

Depending on the severity and the symptoms you have polyphasic sleep could still be possible. There are a few key factors to remember:

  1. If you are suffering from excessive daytime sleepiness and periods of nighttime wakefulness, then establishing a strict polyphasic sleeping schedule will be very difficult. Although the narcolepsy makes it a fight, polyphasic sleep is still possible. Depending on the schedule, narcolepsy could even prove to be an aid.
  2. Sleeping outside the schedule will reduce or prevent adaptation to the schedule. If you frequently fall asleep against your will or have severe daytime tiredness, you can try scheduling extra naps to give you a boost in alertness. If this doesn’t work, then polyphasic sleeping might not be possible for you.  Note that it can take a few days or weeks to fall asleep during nap times, so allow some time to see if it is possible. You can also consult people in a similar situation. Success at adapting also requires a stable circadian rhythm.
  3. Because of the difficulty obtaining SWS, you should always sleep more during cores than recommended for the average adult.  Instead of regular schedules, investigate extended versions of the schedules that have one or even more additional core cycles. Take into consideration how often you have trouble with nighttime wakefulness, and how long it takes you to fall asleep, while designing your schedule.
  4. There are some benefits. SOREM – or proceeding quickly into REM for naps – is already established due to narcolepsy, and adaptation should be a bit easier because of this. Narcoleptics also have little variation to the amount of sleep deprivation they experience, which eases adaptation a bit as there should be no unexpected changes in the level of tiredness that non-narcoleptics get surprised by when entering the next adaptation stages.

Some people suffering from narcolepsy use polyphasic sleeping as a way to deal with the tiredness and irregular sleep schedule.. Rather than decreasing the total sleep time, polyphasic sleep can be used to establish a more strict, regular schedule similar to monophasic sleep in terms of daily sleep time.  This can aid narcoleptics to decrease the amount of sleep attacks and establish a more predictable sleep schedule. Reaching out to various support groups and asking people about their polyphasic sleeping experience is wise.  (Information gathered from an interview with a person suffering from narcolepsy).


If you’re suffering from insomnia, polyphasic sleep could possibly aid you! Some people suffering from insomnia claim to have been able to learn to fall asleep instantly regardless, simply because of the sleep deprivation during adaptation. They also claim to have had an easier adaptation, as they didn’t feel as tired as others do. This is only anecdotally proven, so it’s not guaranteed to help you. Further research into the interactions between insomnia and polyphasic sleep is required. Using naptation to first establish the ability to fall asleep for naps fast, or simply staying awake for over a day before switching to the desired schedule (see later parts of this guide) could prove to give an edge in adaptation, as it could otherwise take a very long time to fall asleep for any naps.

Another point to bring up is the fact that long term sleep deprivation, from for example a failed adaptation that is forcefully kept going , can lead to insomnia1. If this isn’t treated it can even turn out to become chronic2. This means it’s important to understand and take action if adaptation feels like it stagnates, or if one gets stuck in a perpetual loop of oversleeping every few days hindering one from ever adapting. If adaptation stagnates, and it feels like no change has happened in a few weeks, it’s best to change something. Analyze when you’re tired, possibly move naps, add naps or extend the core. If the problem is oversleeping, it’s best to recover all sleep debt and try again. This usually takes at least a week. It should be noted that some studies have concluded that insomnia does not increase people’s mortality rate3. What this means is twofold. Firstly, that sleep deprivation caused by polyphasic sleep should not worry people too much, as it does not increase their mortality rate. Secondly, that even if polyphasic sleep was unhealthy (which is not claimed here), people’s lives are not at stake from the reduction of NREM2. More information about sleep stages can be found in the Sleep mechanics section.


While healthy polyphasic sleep, or polyphasic sleep with enough scheduled sleep time to accomodate for the full SWS and REM needs of people after adapting (normally at least 4 to 5 hours) should not cause concerns for schizophrenia-like symptoms, the same can not necessarily be said about nap-only schedules. A reduction of sleep spindles, which are present in both NREM2 and NREM3, has been linked to schizophrenia and the development of schizophrenia-like symptoms45678. The reason why this should not be a reason for concern on healthy polyphasic schedules is because they do not reduce the amount of SWS people gain each day. The sleep spindles gained from SWS and the small amount of NREM2 left after adapting seem to be enough to not trigger the schizophrenia-development. However, on nap-only schedules regular people do not get enough SWS, which increases the risk of these symptoms developing, as seen in a reddit post with a person who was on the Tesla sleep schedule for 8 months. It should also be noted that a rare few people have noticed mild symptoms of schizophrenia, like paranoia and the feeling of not being alone during the adaptation period to healthy polyphasic schedules. However, these symptoms quickly subsided, leaving no permanent damage at all.

Alzheimer’s disease

Altered sleep patterns are a common sign with people suffering from Alzheimer’s disease. In the relation between Alzheimer’s disease and sleep it is somewhat unclear whether the Alzheimer’s or altered sleep patterns are the trigger for the other part. However, while some research only speculates which part is the trigger, other papers might give a hint which one is the trigger and which one is the result of said trigger. The relation between sleep and Alzheimer’s is still under research, and scientists are working hard to uncover it’s full relation with sleep. Regardless, Alzheimer’s patients have been noted to have more sleep disturbances and changes in their sleep-wake rhythm9. This does not however mean that a change in your rhythm would be linked to developing Alzheimer’s, but rather that it’s a characteristic of Alzheimer’s patients. Disordered sleep, or bad sleep that results in sleep deprivation of some kind, has however been linked to developing Alzheimer’s1011, strengthening the point that people should make sure to sleep at a consistent time and minimize the time spent sleep deprived. As one article points out, a reduction of SWS is especially linked to the development of Alzheimer’s. Because of this it can be assumed that the reason disordered sleep is linked to Alzheimer’s is because the total amount of SWS is reduced. This is probable to be a cause because of the fact that the glymphatic system operates at its highest capacity during SWS, and is responsible for clearing out metabolic waste that is linked to developing Alzheimer’s12. A smaller percentage of REM sleep compared to the total amount of sleep is also possibly a culprit for developing Alzheimer’s. However, what is interesting to note is that polyphasic sleepers have a much higher percentage of REM sleep compared to monophasic sleepers (while the total amount or REM stays the same), and it is therefore uncertain how the adaptation process affects the development of Alzheimer’s. The safe assumption is still that REM deprivation is a risk regarding the development of Alzheimer’s. Because of these findings it can be concluded that nap-only schedules carry a risk, since they reduce the amount of SWS and REM regular people have each day. A healthy polyphasic schedule should not increase the risk of developing Alzheimer’s as long as one adapts successfully and doesn’t get stuck in a loop of regularly oversleeping. It is also important to maintain a healthy circadian rhythm, as circadian disruptions have been linked to developing Alzheimer’s13. Elevated beta amyloid levels, which are the waste products of the brain responsible for developing Alzheimer’s, is known to reduce the cognitive performance of people14. The community is currently developing a testing application to better examine the effects of pre-during, and post-adaptation polyphasic sleep on cognitive performance to gain further insight into this matter.


The term “hypersomnia” can be viewed as an umbrella-term for all cases that cause people to sleep for long periods of time. For example exercising intensely or skipping sleep for a few days could trigger a surge of longer sleeping, which would be classified as hypersomnia. Still, in order to get the official diagnosis of chronic hypersomnia the symptoms (long sleep durations or excessive daytime sleepiness) should have persisted for at least 3 months15. Hypersomnia can be categorized into two main categories; primary hypersomnia and secondary hypersomnia. Primary hypersomnia can be prevalent in narcolepsy and idiopathic hypersomnia, and can be seen as a symptom without other disorders. Secondary hypersomnia is caused by another disorder, for example by clinical depression, obesity, sleep apnea and some medications. Most types of hypersomnia are incurable, and are advised to be clinically examined. Fortunately, the hypersomnia caused by sleep deprivation is only temporary and will subside after recovering. Treatments for chronic hypersomnia frequently involves pharmaceutical intervention from stimulants or anti-depressants.

People who suffer from hypersomnia can still sleep polyphasically, but it should be noted that the standard schedules will likely contain too little sleep for them. Since they have elevated SWS and/or REM needs, this will need to be factored into the scheduling, most likely resulting in the need to do extended schedules. If you are using stimulants to combat chronic hypersomnia you are advised to consult with a doctor about the possibility to sleep polyphasically, as it is crucial to be able to fall asleep for naps, if the schedule contains them. There might be alternative stimulants that you can use with shorter half-lives, so be sure to suggest a change of stimulants to your doctor if necessary. Never abandon medications without consulting a physician first. Naps are considered an alternative way to gain energy, which means that polyphasic sleep is great for people suffering from hypersomnia. Sleeping polyphasically could possibly result in you not needing to take stimulants to stay awake anymore, all because of the additional alertness boost provided by the naps! Segmented sleep can be relatively medication-compliant as a schedule because of the long gaps of wakefulness, so if abandoning medications is not an option this schedule can still work with stimulants.

Sleep apnea

Sleep apnea is caused by muscles in the throat relaxing, which results in the airway being blocked. This causes a drop in blood oxygen saturation, which arouses your brain from sleep and releases adrenaline. Many people are not even aware of these arousals. If you have sleep apnea without treatment, your brain partly wakes you up when your airway collapses, specifically, when your blood-oxygen starts to drop due to not being able to breathe. When you wake up, your throat muscles tense up again, and breathing resumes normally. Often you will not become conscious when this happens, so you may have severe sleep apnea and not be aware of it. This cycle of sleeping > airway collapses > arousal > breathing resumes > return to sleep can happen many times per hour16. Less than 5 events per hour is considered normal, 5-15 is minor, 15-30 is moderate, and more than 30 per hour is severe17. What this means is that the brain cannot fall into SWS for more than a couple of minutes at a time depending on the severity, meaning the quality of the sleep becomes very poor18.

Risk factors for developing sleep apnea include being overweight, snoring, retaining tonsils, having a large circumference of your neck, not sleeping in a lateral sleeping position and other genetic factors which mostly have to do with neck/jaw/facial structure16. There are several methods of treatment, depending on severity. By far the most common is a CPAP machine (Continuous Positive Airway Pressure). It inflates the lungs and airways, preventing them from collapsing16. For less severe cases, a dental appliance can be used, which simply holds the tongue towards the front of the mouth19. For more severe cases, or for those who find a CPAP machine too uncomfortable or claustrophobic, or cannot adapt to the difference in breathing with a CPAP machine, it is advisable to consult for alternatives with a doctor.

Because polyphasic sleep relies on optimizing sleep, adapting to a schedule will not be possible without the proper treatment for the disorder. A proper treatment of sleep apnea combined with people being used to the equipment, or in other words have no trouble falling asleep quickly, allows the quality of sleep to return to normal levels, which means that attempting a polyphasic sleep schedule becomes possible at that point.


Sleep deprivation is the second most common trigger for seizures, and some people have it as their only trigger20. If you have epilepsy you should not sleep deprive yourself, which is inevitable during adaptation, meaning polyphasic sleep is not for you.


If you have a severe case of ADD or ADHD and take adderall, methylphenidate (ritalin), or similar medicines, then polyphasic sleeping could be very difficult for you. Both adderall and methylphenidate are stimulants, and are going to make falling asleep much harder unless you take small doses a long time before the sleeps. Fast release adderall has a half life of about 10 hours, while methylphenidate has a half life of about 3h. Methylphenidate is also used as a form of treatment for narcolepsy which similarly to  polyphasic sleep contains SOREM. Consult a physician about dosages and possibilities to do polyphasic sleep while taking similar medication.

Heart conditions

Sleep deprivation increases stress, which in turn increases blood pressure21. While this does not pose significant risks in healthy individuals, the risk of having a heart attack increases in individuals with heart conditions, so it should be completely avoided if you are at risk of getting a heart attack is already elevated.


Being sick with a temporary disease, such as the flu or a fever, is a normal reaction while adapting. If you get sick during or before adaptation it’s important to take a break and recover before continuing/starting the desired schedule. Being sick increases the SWS need significantly, causing the body to insert it into several sleep cycles in turn increasing the overall sleep need. The additional sleep gives the immune system a boost in fighting off your sickness22. If you disrupt your sleep before waking naturally, you will likely have skipped out on SWS. This hinders recovery, and it can both prolong the sickness and risk secondary health problems.

For this reason, it is strongly advised that whenever a polyphaser is sick, they switch to a schedule which would allow for a greater amount of SWS. Traditionally this would mean dropping back down to monophasic sleeping until the illness has been dealt with, or adding extra cycles in SWS-favourable times to the entrained schedule’s existing sleep blocks. It is also possible to extend existing naps or cores during the time of sickness, but there should not be a limit as to how long you allow yourself to sleep. If one gets sick during adaptation starting a healthier lifestyle (exercising, eating healthy etc) is recommended before re-attempting polyphasic sleeping. Sleep deprivation weakens the immune system23, so giving it every boost possible is wise.

Chronic diseases

Sufferers from chronic diseases, like diabetes, cardiovascular diseases, sleep apnea, and so on, should consult with a medical doctor about attempting a polyphasic sleeping schedule. Ask them about increased health risks that come with adaptation, if for example increased tiredness or a weakened immune system (bigger list in later parts of the guide) is considered a health hazard with the condition.

REM sleep and depression

There appears to be a link between REM sleep frequency/quantity and depression. In particular, clinical depression appears to be proceed by REM sleep alterations24. While it is not clear whether this is cause or symptom, it indicates a link between depression and REM sleep. SSRIs (common antidepressants) appear to function by reducing both REM quantity and also REM deprivation symptoms25. Consequently, polyphasic sleep may worsen depressive symptoms,  due to REM deprivation during adaptation. Observations have been made where the schedule would start without any depression with a gradual increase in symptoms during adaptation which can prove detrimental.

Sleep deprivation also causes mood swings, which makes emotions even stronger. Adapting to a polyphasic sleeping schedule will also most likely bring out loneliness, as polyphasic sleepers are awake during the time everyone else sleeps.

If you’re suffering from depression, polyphasic sleep can still be possible. It can be used as something to strive for, possibly getting you out of depression eventually. However, in general you should be careful about adapting to a polyphasic schedule during this time of your life especially since sleep deprivation during adaptation can lead to additional stress and anxiety.

Main author: Crimson

Last page update: 11 March 2020

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