From reading accessible information about Free Running Sleep Disorder (FRSD) in humans, I understand it is a chronic and cyclic sleep disorder of a totally unentrained 24-hours circadian rhythm.


I recognize a term like totally unentrained 24-hours circadian rhythm as somewhat vague, but a description I find practical is as follows:

Each day, a person would naturally feel enough tired, to sleep, a bit later than the day before; thus, that person won't be able to naturally fall asleep before that later time;


Each day, that person would naturally wake up a bit later than the day before.

It might be reasonable to say that an FRSD sufferer totally lacks the common ability to fall asleep when feeling a bit tired.


The disorder is chronic and cyclic because the human brain will stubbornly "remember" the need to permit sleep (as well as waking up) later every day.

Approximate exampling of the problem is available with this diagram:

Day 01: Wake up at 06:00
Day 02: Wake up at 06:30
Day 03: Wake up at 07:00
Day 04: Wake up at 07:30
Day 05: Wake up at 08:00
Day 06: Wake up at 08:30
Day 07: Wake up at 09:00
Day 08: Wake up at 09:30
Day 09: Wake up at 10:00
Day 10: Wake up at 10:30

Day 11: Wake up at 11:00
Day 12: Wake up at 11:30
Day 13: Wake up at 12:00
Day 14: Wake up at 12:30
Day 15: Wake up at 13:00
Day 16: Wake up at 13:30
Day 17: Wake up at 14:00
Day 18: Wake up at 14:30
Day 19: Wake up at 15:00
Day 20: Wake up at 15:30

Day 21: Wake up at 16:00
Day 22: Wake up at 16:30
Day 23: Wake up at 17:00
Day 24: Wake up at 17:30
Day 25: Wake up at 18:00
Day 26: Wake up at 18:30
Day 27: Wake up at 19:00
Day 28: Wake up at 19:30
Day 29: Wake up at 20:00
Day 30: Wake up at 20:30

Day 31: Wake up at 21:00
Day 32: Wake up at 21:30
Day 33: Wake up at 22:00
Day 34: Wake up at 22:30
Day 35: Wake up at 23:00
Day 36: Wake up at 23:30
Day 37: Wake up at 24:00
Day 38: Wake up at 24:30
Day 39: Wake up at 01:00
Day 40: Wake up at 01:30

Day 41: Wake up at 02:00
Day 42: Wake up at 02:30
Day 43: Wake up at 03:00
Day 44: Wake up at 03:30
Day 45: Wake up at 04:00
Day 46: Wake up at 04:30
Day 47: Wake up at 05:00
Day 48: Wake up at 05:30
Day 49: Wake up at 06:00

The described approximate cycle will repeat at self about each 49 days until the disorder has disappeared or as long as it is not treated.

Symptoms and Prognose

If an FRSD sufferer is untreated and would forcefully be awoken and forcefully stay awake thought the day (before natural awakening should have been occurred), side effects such as sleepiness, headaches, and possibly "seeing yellow stars" and more would occur throughout the day.

If treatment is unavailable or rejected;
Monetary income wouldn't be optional from a job in predefined time frames (such as from 08:00 to 14:00 every day), and either a job in differentiating time frames or free running in itself would be needed, or otherwise another source of monetary income would be needed (such as social security, grace organization, family, etc).


I understand that as of the second decade of the 2000's, the cause of this problem in the general audience is unknown and there might be more than one cause:

  • The problem is likely organic, whether if innate or if evolved sometime after birth.

  • It is more common in people with different conditions of blindness

  • In people without different conditions of blindness it usually start in teen era and might naturally disappear only at, or after, age 30.

  • In non blind people, selective impotency of melanopsin receptors, might cause it.


I understand that as of the second decade of the 2000's, this problem was considered among some sleep physicians to be very hard to manage, with the first line treatment being instant release melatonin in steadily growing dosages (no more than about 20mg, which if this dosage was reached, other treatment would be considered),
but not only it often doesn't help to entrain the circadin rhythm and the pathway is different, it can include serious side effects such as vivid mightmarish dreams which are commonly reported.

If instant release melatonin doesn't work (or doesn't work good), a subjective, complex treatment might be given and would be likely similar to that of chronic insomnia:

  • Likely including small dosages (4≤mg) of prolonged release melatonin, possibly combined with other long-term insomnia medications as a synergistic treatment.

My question

How does Free Running Sleep Disorder (FRSD) in humans get treated as of 2020s?

  • $\begingroup$ "I understand that as of the second decade of the 2000's, this problem was considered among some sleep physicians to be very hard to manage" What source did you use to come to this conclusion? What specific date was it from? Any reason to believe current treatment (perhaps only a couple years later) would be drastically different than what you found in that source? Otherwise, +1 for a well-researched question. In fact, it perhaps includes a bit too much background info deviating from the question at hand. :) $\endgroup$
    – Steven Jeuris
    Jan 20, 2020 at 15:10
  • $\begingroup$ This particular part is based on synthetic understanding ; you are welcome to reject it. $\endgroup$
    – user24978
    Jan 20, 2020 at 15:12
  • $\begingroup$ Okay, thank you for clarifying! Note that in case the crux of your question is based on a 'synthetic understanding', it might make sense to highlight that in the question so that people who might answer the question understand on what your current understanding is based. $\endgroup$
    – Steven Jeuris
    Jan 20, 2020 at 15:53


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