Sleeping should be one of the easiest things in the world to do. However, about 30-40% of adult U.S. population has trouble going to sleep or staying asleep according to the National Center for Sleep Disorders. Why is such a simple thing so difficult for many people? It has to do with the circadian rhythm - your body’s biological clock. This internal clock regulates our sleep-wake cycles and if it gets out of sync (like it does when experiencing insomnia), it can cause all kinds of other health and mental problems due to lack of adequate sleep.

Delayed sleep-wake phase disorder (DSWPD) is one of the more commonly recognized disorders of the circadian rhythm. It is often mistaken for sleep initiation insomnia due to the late or delayed onset of sleep (2 hours or more). Delayed sleep-wake phase disorder typically emerges during puberty and persists into adulthood. People suffering from this disorder often refer to themselves as “night owls” because they are unable to fall asleep at an acceptable time. It becomes a bigger problem when they need to adjust to an earlier wake up time for school and jobs that require a 9 - 5 schedule.

What happens is that people with the disorder can’t fall asleep at an appropriately early time in the evening and then have great difficulty to wake up at a desirable time in the morning. The average person can skimp on a few hours of sleep and be fine, as long as it happens infrequently. But if this becomes the norm, the sufferer will begin to incur a sleep deficit which they will try to compensate with getting extra sleep at weekends. It can lead to chronic, and often quite severe sleep deprivation.

However, the delayed sleep phase disorder is characterized by normal sleep quality and duration when released from schedule constraints. It just happens outside of the normal timeframe. 

The symptoms of the delayed sleep-wake phase disorder

Individuals with this sleep disorder may experience:

  • inability to fall asleep at a socially acceptable bedtime
  • dependence on sleeping aids to fall asleep every night
  • depression or irritability resulting from daytime sleepiness
  • daytime sleepiness that interferes with work or school schedules
  • no other sleep problems
  • dependence on caffeine to wake up or stay awake
  • complaints of insomnia.

The cause of the delayed sleep-wake phase disorder

To pinpoint an exact cause is difficult. Because this disorder is common among teens, researchers think that it may have something to do with naturally occurring changes in hormonal levels when we hit puberty. Just like other circadian rhythm sleep disorders, delayed sleep-wake phase disorder is a neurological condition that involves changes to the brain’s regulation of sleep pattens.

How is DSWPD treated?

It is easy to confuse DSWPD with other types of insomnia. You should make an appointment with your doctor if you are experiencing the symptoms listed above. Consulting a sleep specialist may also help to address other disorders that DSWPD may be associated with, such as obsessive compulsive disorder, affective disorders, autistic spectrum disorder, and attention deficit hyperactivity disorder.

The doctor will do a thorough exam and take your medical history into account when prescribing a treatment method. It may help to record your sleep times in a journal to see your progress. A regular sleep study is not needed if the diagnosis of DSWPD is certain. 

The main goal when it comes to treating DSWPD is to advance the onset of sleep slowly and gradually over time so that the body adjusts its internal clock (the circadian rhythm) to the new schedule making it easier to maintain.


Timely use of melatonin supplements has produced good results without the risk of addiction, as is the case with some sleep medicines. It is generally very well tolerated and considered to be safe for use when taken responsibly. Although there is lack of data, its use is avoided in pregnancy and breastfeeding.

Melatonin is considered a supplement and available over the counter in many grocery outlets and pharmacies across the U.S. It is harder to obtain in the UK and EU, as a prescription is needed for purchase. 

Doses are typically set to 0.5mg daily as a sleep-inducer. Patients should be taught that melatonin is potentially less sedating or hypnotic than prescription sleeping aids. It works more as a signal to the brain and body that sleep time is approaching and helps you to relax and fall asleep naturally. 

Melatonin should be taken approximately 30 minutes to an hour before the desirable bedtime. If your schedule demands you to be asleep by 10pm, take melatonin no later than 9:30pm.  

As consistency is very important, patients should set alarms to remind them to take melatonin. When it is used correctly and consistently, it can gradually bring on a 90-minute phase advance. In the first week you should aim for a 30-minute advance. Once a new shortened phase has been achieved, the sleep time can be recalculated, and the dosing time made earlier until the desired results are achieved. For the process to be successful it must be maintained for no less than 6 weeks.

You may not be able to find the prescribed dose of melatonin in grocery stores. In that case a 0.5mg dose can be obtained by cutting a 2mg timed-release melatonin tablet into 4 pieces. However, this will significantly disrupt the coating and change it to an immediate-release formula.

Screen time at home

In addition to appropriately dosed and timed melatonin supplementation equal diligence is needed to avoid the sleep-suppressing effects of bright evening light from incandescent bulbs and electronic screens. 

The main key is to avoid the blue screen light. One way to minimize light in the evening is with a dimmer switch and blue-light filtering sunglasses or goggles. It is recommended to use them from sunset until you go to bed. 

Some patients have reported significant success in just minimizing exposure to artificial indoor light until bedtime.

Bright light therapy

While it is necessary to avoid bright light in the evening hours because it delays the sleep phase shift, exposure to bright light in the early morning is a necessary and beneficial tool for resetting your internal clock.

Melatonin is highly beneficial in helping to regulate the circadian rhythm and getting sleep back on track. Daylight is another. It is absolutely essential for the success of your efforts to regulate your sleeping habits. Bright morning light is encouraged for a minimum of 30 minutes per day delivered as soon as possible after waking. If you cannot go outside first thing in the morning due to bad weather or other circumstances, sitting next to a well lit window is the next best thing.

In winter months when bright light is less available, artificial light therapy can be substituted. There are a variety of light boxes available for this purpose. Studies have been performed with a variety of light intensities and durations. When using lightbox therapy, the individual should be no farther than 50cm from the light source for maximal efficiency. If using a larger device, position it 85cm away. The best results have been obtained using a bright light with 10,000 lumens for 30-minute durations upon awakening. 

While bright light therapy is very effective, some patients find it difficult to keep up. In this case a wearable device may be more suitable. All that is needed is a LED-light emitting device such as glasses. Many patients report success using these devices, although there is no scientific proof of their ability. It is recommended as an alternative when other methods are not available or limited.

Good sleep is a vital part of good health. We spend approximately a third of our lives sleeping and it makes a huge impact on how well we function in the remaining two thirds of our lives. Adequate sleep is necessary for good health, and indeed our survival as a species.