Substance Use


Substance use, in the form of drugs and medications, are everyday consumables. In the context of sleep, they can affect sleep onset or even alter the sleep architecture. While monophasic sleepers may be less susceptible to these, polyphasic sleepers do have to consider these factors and possibly change their lifestyles to succeed. Thus, this article details several examples of such substances and their effects on sleep.



Caffeine has a half-life of around 5-6 hours1. Caffeine will mostly be gone from the system after around 12-18 hours. It can still affect you depending on the initial amount consumed, however. It works by competing with adenosine for the same receptor type, which can reduce drowsiness. However, it also has some other effects, including increased heart rate2, increased sleep latency, and reduction in sleep quality3.

The increased sleep latency is particularly detrimental for polyphasic sleepers. For example, in one observed case, after consuming a moderate amount of coffee and caffeinated soda around 3 hours before sleeping, the sleep latency went through some negative changes. It then took half an hour to fall asleep and almost an hour to reach NREM2 as reported by an Olimex OpenEEG. It is worth noting that the experimenter was rather sleepy in the process. 

Polyphasic sleep application

The general consensus within the polyphasic sleeping community is to completely remove caffeine. However, this likely will lead to caffeine withdrawal symptoms in long-term caffeine consumers. This is because the body responds to the constant caffeine supply by upregulating the adenosine receptor count4. Furthermore, a long-term tolerance and dependence on caffeine is also a result of this process.

  • It may be favorable to first spend several weeks on regular (or even extended) sleep schedules to complete the withdrawal process.
  • Then, start an adaptation if you plan on removing caffeine from your diet.

However, Puredoxyk mentions in her Ubersleep book that she took soda to stay awake during her initial Uberman adaptation. She also reportedly drank small amounts of coffee and other beverages while sleeping polyphasically. Thus, it may be advantageous in certain situations.

  • Small doses of caffeine to offset sleep deprivation symptoms during an early period of adaptation or during the initial sleep deprivation period is possible.
  • One common trick is a “coffee nap” where you consume caffeine immediately before sleeping. However, this is normally not recommended; caffeine metabolism is fairly fast5 when consumed in liquid form.
  • However, one can avoid this by using caffeine tablets. These generally have delayed onset. Due to the long half-life of caffeine, future sleep sessions can be affected especially with small wake periods between each sleep. For this reason, caffeine naps should be used only when necessary.

Decaffeinated coffee and similar drinks are not actually caffeine-free. The decaffeination process only removes between 70 and 86% of the caffeine in reality6.

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Caffeine on Segmented sleep

Caffeine consumption is overall acceptable on very few schedules, namely Segmented or other very extended schedules. 


Caffeine is present in several products; thus, restricting consumption of these to a certain degree is a good idea.

  1. Coffee (high caffeine content)
  2. Decaffeinated coffee (low caffeine content)
  3. Black tea (moderate caffeine content)
  4. Green tea (low caffeine content)
  5. White tea (negligible caffeine content)
  6. Dark chocolate (high caffeine content)
  7. Milk chocolate (low caffeine content)
  8. Energy drinks (moderate caffeine content)
  9. Sodas (varying caffeine content), caffeine free sodas include but are not limited to:
    • Caffeine free diet coke
    • Sierra mist
    • Sprite
    • Seagram’s ginger ale
    • A&W root beer
    • 7-UP

A rough estimate of caffeine content per 100ml (or 100g):

  • negligible = 1 mg
  • small = 15-20 mg
  • moderate = 30-40 mg
  • large = >60 mg

Polyphasic sleepers should avoid even products with small amounts of caffeine. They can still affect you if you consume in large amounts, or if you’re sensitive to caffeine. Nevertheless, the point after which caffeine will noticeably start affecting you is highly individual. Some people have very low thresholds of under 10 mg, while others have very large thresholds of up to 600 mg7.

On the other hand, the positive effects from caffeine wear out before the negative ones. This results in an energy low which increases oversleeping chance while still decreasing sleep quality.


Alcohol consumption can increase depth and length of slow-wave sleep (along with the SWS need). In addition, large amounts (more than 1 or 2 drinks) can reduce REM sleep. Drinking significant amounts of alcohol also leads to significant sleep architecture disturbance, which can completely wreck a polyphasic adaptation. The most noticeable affect is the elevated risks of waking up during REM or SWS8. Consequently, it is not advisable to drink huge amounts of alcohol while sleeping polyphasically.

It is also not advisable to drink alcohol prior to any REM-oriented sleep sessions (e.g, dawn nap/core). However, it may be acceptable to drink a small amount prior to SWS-oriented sleep sessions without significant damages. Still, sleepers should avoid large volumes; avoiding drinking entirely is probably the safest option. Ending consumption 2-3 hours before a core and drinking a lot of water with a snack can minimize harm to sleep quality.

The amount of consumable alcohol after adaptation depends on:

  • How strict a polyphasic schedule is
  • How difficult the schedule is
  • Drinking frequency

Overall, be cautious and test in small increments.


Nicotine is a stimulant with similar effects to caffeine. It has a half-life of around 2h9, after which it is metabolized into cotinine. However, cotinine is also a stimulant and has a half-life of around 19h10. Consequently, it is likely that smokers will have harder time adapting to a polyphasic schedule; as the sleep onset will increase and overall sleep efficiency will decrease11.

So far, there are no reports of any smokers having successfully adapted to any polyphasic schedule.


There is very limited research on how cannabis affects sleep, let alone polyphasic sleeping. Currently, research and anecdotal evidence points to cannabis reducing the amount of REM sleep and increasing the amount of SWS (possibly also increasing the SWS daily need)12. As a result, it should be avoided during adaptation.

Additionally, consumption should remain at moderate levels after adaptation. Cannabis also seems to assist with falling asleep, but an adaptation still needs to take place.


It is best to avoid all drugs that alter sleep directly. Specifically, drugs that directly alter the sleep architecture, the relative proportions of sleep stages or increase alertness or sleepiness; this also includes drugs with indirect effects, such as inducing loss of self-control. This is especially important during adaptation as you may need to stay awake through periods of extreme tiredness.

To better understand whether and how a particular (prescription) drug could affect your sleep, research their half-life, effects on sleep, your mood and control from studies and information labels. Regardless, if you’re unsure about consumption of a certain drug, consult appropriate medical specialists regarding its effects and possible side effects. You can also ask in the Discord community chat server or Reddit for user experience of the same or similar drug.


Melatonin may be useful for setting core bedtime earlier or later than it has been, just like its common use for jet lag. Thus, this is especially useful for setting your circadian rhythm on the first 1-4 days of your new schedule.

Polyphasic sleepers should NOT to use extended time-release melatonin, as those are for monophasic sleeps. Typically, only take for a few nights at a time. The amount of melatonin effect will vary per person, and overshooting the necessary amount is a bad idea. It will make waking up very hard. Melatonin toxicity is usually extremely low, yet common doses range from 1-5mg, or 10mg in rare cases. Using melatonin for extended periods of time is not advisable. However, it is best to teach the body to produce its own melatonin rather than relying on external sources. Melatonin should also not be used for the naps.

Main author: Crimson

Page last updated: 24 December 2020

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