I am 34 years old and have a long history of difficulty sleeping. My doctor diagnosed me with delayed sleep phase disorder (DSPD). It appears that my “normal” sleep time is 4 or 5 a.m., and I typically wake up around noon or 1 p.m. I would like to shift my sleep earlier so that I can fall asleep around midnight or even 11 p.m. I purchased a light box per my doctor’s instructions, but he is not sure how/when to apply the light box. What time should I use the light box? Immediately upon waking at noon? If I do so any earlier, it will disrupt my sleep.

Each case of DSPD needs individual clinical consideration because multiple factors can cause the sleep pattern, and therefore approaches to treatment will vary.  Thus we can only suggest a broad strategy here.  Light therapy can start at your current wake-up time, as you say. However, waking up for light therapy half an hour earlier than usual may speed up progress.

In conjunction with morning light, it is critical to control bright white (and bluish) illumination for several hours before sleep. Ways to do this include using blue-blocking glasses, such as the protective lenses we recommend on our site. You can also install f.lux software, available for free, on your computer, and Night Shift software on your iPad and iPhone.  Room light should be kept low, but comfortable, allowing clear vision at a distance.  Refrain from eating for at least three hours before current, expected sleep onset.  

The bedroom should be dark, ideally with blackout shades for protection from the dawn twilight and early morning sunlight during hours you are sleeping. Given the darkness of the bedroom, it is helpful to set a bedside dawn simulator to provide increasing light, from darkness to maximum illumination, in the 30 minutes before you need to get up.  Set an alarm clock for back-up in case you don’t wake up spontaneously to the dawn signal.

If you are not oversleeping, after a few days, it will be time to begin shifting wake-up time progressively earlier, probably in 30-minute steps every 3-4 days.  Dawn simulation and post-awakening bright light therapy should be shifted together. Be careful not to rush the process. If you shift too rapidly, you may find yourself flipping into a delayed sleep pattern even more extreme than when you started. Therefore, the process requires close attention. Make sure you are waking up comfortably at each new wake-up time  before you try shifting your wake-up time 30 minutes earlier. Each 30-minute change may take just a few days, or require a week.

The dose of bright light therapy can make all the difference. The best length of time for a session at 10,000 lux can vary substantially between individuals. Thirty minutes will be effective for some people, but others will need 45 or even 60 minutes. Keep in mind that you may be successful at waking up earlier long before you are successful at falling asleep earlier to the same extent. Consequently, there may be an interval of days, or even weeks, when you don’t get as much sleep as usual.  At some point, however, you should be able to compensate for earlier waking with earlier bedtimes. Look for signs that you are starting to get sleepy earlier than expected, and yield to your sleepiness rather than continuing nighttime activities. However, don’t force yourself into bed before you get sleepy.  

Beyond this general strategy, you may also need to practice good sleep, or consider the influence of your medications on sleep.  

In short, you will be lucky if you can pull off this change on your own, without a clinician’s monitoring and guidance throughout. That said, many people have had such luck, and it is well worth the trial, even if it fails.  

I am traveling to a time zone that is 12 hours ahead. I will be in that time zone for 12 days (traveling east to west). If I buy the sunglasses you recommend, how do I adjust the light or what time of day should I wear the sunglasses to overcome jet lag?

You’ve chosen to take on a most difficult challenge, given the huge degree of phase shift you’re trying to make your body do rapidly, and given the tiny chance of finding a non-stop flight for this route. The arduous travel of 30 hours alone makes this a challenge, even without jet lag. For such questions, I usually refer people to the book How to Beat Jet Lag: A Practical Guide for Air Travelers, published years ago by Walter Reich, Norman E. Rosenthal, Thomas A. Wehr, and me. It’s available for just pennies a copy (plus shipping) from Amazon at http://ow.ly/VzVd0. (Disclosure: the book is now officially out of print and the authors no longer receive any royalties.) For the specific trip you mention, you’ll want to avoid light before 10 AM on the first day of travel. From 9 PM – 3 AM (original time zone) you will want to stay awake and expose yourself to bright light. This will be a challenge because of the late hours when your body will likely be doing its best to drag you off to sleep. At 3 AM (original time) reset your watch to the destination time zone. Then after 4 pm (destination time) avoid light again. This is the start of inducing the phase delay that you will want for your westward travel. Your “time-light” efforts will continue for the next three days at your destination, and those details along with critical caveats and safety guidelines are detailed in the book I mentioned. ―Dan Oren, MD

I have just been diagnosed with delayed sleep phase. My body clock tries to make me sleep from 2 a.m. until 10 a.m., but I must wake up for work at 5:30 a.m. The doctor prescribed Ambien, but after trying it, I still have great difficulty waking up, even after eight hours of sleep, and am very groggy all morning. My doctor and I discussed light therapy but he didn’t seem to feel I needed it since my delay was not severe. I wonder if the medicine is making me fall asleep on time, but my body is still producing melatonin at the wrong time. Could this be the problem and could light therapy help? I am a teacher and in the summer when I’m not working, I sleep until 9 or 10 a.m. and then spend time outside. I don’t have a sleep problem then.

Very well expressed, but you are presenting a complex of issues. Mostly importantly, your doctor is wrong: light therapy provides a very effective solution to mild sleep phase delay. Beyond that, your delay is about three hours, which we would consider quite serious. A major complication involves your workday rise time at 5:30 a.m., however. If you were to take light treatment at such an early hour, it would act to exacerbate your delayed sleep phase. To move your body clock earlier, the light therapy strategy requires using lights near the end of your “internal night,” most likely after 8 a.m. when you are already out of the house. You could get a grip on this problem in late summer or on winter vacation. After a few days of light at 8 a.m., you would begin to step up the light progressively earlier in order to advance your body clock. You might also make headway by using low dose slow-release melatonin at about 10 p.m., whether or not in conjunction with light, and then moving the dose progressively earlier. Because of the complexity of your situation, we urge proceeding under expert clinical guidance. For relevant background, see the Termans’ chapter in Principles and Practice of Sleep Medicine, downloadable free at www.cet.org. And perhaps share it with your doctor!

Is it true that for society in general, people have a mind of their own by disrespecting or not taking account of their circadian rhythms, especially in cases of undiagnosed, Delayed or Advanced Sleep Phase Disorder (DSPD, ASPS)?

Thank you for this provocative question. Surely, it is true that most people with DSPD and ASPS, although they realize their sleep is displaced relative to the norm, do not identify the situation as a “disorder” or attribute it to their circadian rhythms. Many of them accommodate it by making a circle of friends with similar sleep patterns (active phone calling after midnight, etc.) and finding jobs that do not require a 9-5 work schedule (bartending, acting, free-lance writing, etc.) Importantly, however, many also experience depression, and cannot maintain self-supporting employment or family life. Some, with partners who sleep normal hours, develop serious conflicts at home (even with the threat of divorce). When such problems develop, you will recognize that you have a serious problem, but still you are unlikely to attribute it to a circadian rhythm disturbance.

The Center for Environmental Therapeutics has a major goal of teaching people with ASPS and DSPD the nature of the problem and guiding them toward effective treatment and adjustment using the most potent method available–light therapy. Light therapy needs to be complemented with restricted lighting at other times of day in order to normalize the sleep pattern. In DSPD, for example, it is important to receive ample light exposure after sleep, but to minimize light exposure before sleep. The opposite holds for ASPS. People have achieved dramatic improvement using these simple techniques.

Do most people respond to light therapy even at the “right time” for phase advances or delays? Does it need to be done at late night or early morning when it is dark?

The circadian rhythm system is most responsive to light–producing phase shifts–when it is done therapeutically at the edges of a person’s “subjective night.” What is subjective night? It’s not the same thing as night outdoors. People vary by as much as six hours (early types, late types; larks, owls) in their subjective night. How can you find out about your subjective night and the specific time that morning light therapy is expected to work best for you (by phase advancing your internal clock)? Complete our Automated Morningness-Eveningness Questionnaire at www.cet.org, and you’ll find the answer.

I suffer from delayed sleep phase disorder (DSPD) and for years have been using a bright light and radio on a timer to wake up. Also, after I started following Ask the Doctor on cet.org, I became much more careful to use dim lights closer to bedtime. These have both been very helpful. (I am also using CET’s ionizer, and although it doesn’t seem to affect my DSPD, it has greatly reduced the chronic congestion I’d been suffering–my wife reports that it has almost completely eliminated my snoring.) Additionally, I have been using melatonin occasionally, but when I use it I take it right when I’m going to bed (usually 6-7 hours before my projected wake time) or if I wake up an hour or two later and am tossing and turning. So I read with interest your recommendation to take melatonin 12 hours prior to wake time. Am I potentially doing more harm than good taking it later than that?

The reason for the earlier melatonin dose is that it reinforces the action of the light in setting your internal clock earlier, thereby making it easier to wake up. This use of melatonin is not as a sleep aid, and for that reason you should use a very low dose (not more than 1 mg) that will not make you sleepy before your bedtime. The potential problem using melatonin when you wake up at night is that it may stay in the bloodstream after wake-up time, contributing to difficulty waking and morning grogginess.

It is mainly thanks to CET’s website that I have been self-treating with a light box for delayed sleep phase disorder (DSPD) over the last six years. I can really see that it is a powerful treatment, far more effective than everything else I have tried–and I tried many, many things over the years, from diet alterations to sleeping tablets to Chinese medicine and much more. Although the light treatment works, I still find it difficult to stick to a “normal” schedule. A few times I have failed to force myself to get up to use the lights in the morning (especially on the weekend it takes a lot of willpower) and I’ve found that the consequences of just delaying the treatment even by an hour or so for one day are that it takes three or four days of using the lights correctly in order to get back on track. Are there any tips or tricks to help avoid this happening, or to help me resynchronize faster if it does happen? In your experience, do you find that long-term DSPD sufferers eventually “unlearn” these habits and find it easier over time to stick to a regular schedule, or will it always require as much willpower and self-discipline as it does for me.

This is a great, insightful contribution to our forum. Some thoughts in response: If you are finding it difficult to wake up on schedule, it’s a sign of that you have gained only partial effect. We want it to become easy to wake up at the target time. You might achieve this by increasing your light dose with higher lux (but please, not above 10,000 lux) or longer session duration. If the session gets as long as an hour, take a brief break in the middle for some stretching. Second idea: Short of using a dawn simulator, attach your bed lamp to an electronic appliance timer set for 15 minutes before wake-up, and then proceed to the bright light session. If you find the bedside light disturbing, stop using it. Third idea: Take a low-dose melatonin capsule (not more than 1 mg) in the evening 12 hours before the scheduled light session. This should reinforce the phase-shifting effect of morning light without making you sleepy immediately. Thus, you’ll go to sleep about four hours after taking the melatonin if you are an eight-hour sleeper. If the melatonin disturbs your sleep, stop using it. You are correct: once you slip later, you should not resume the lights at the target time, but rather edge earlier over several days from when you are waking up. Finally, during the four hours before bedtime, keep your room lights low-–just comfortable enough for reading, socializing and watching TV–and avoid exercise and stimulating work activities that can contribute to difficult sleep onset.

I think I have delayed sleep phase disorder (DSPD). I took the Automated Morningness-Eveningness Questionnaire and got some interesting suggestions I’d like to try. Even when I get sleepy in the evening, I tend to stay up for an hour or two or three, and then the next thing I know, it is 1:45 a.m. (or 2:45 a.m.) and I have an alarm set for 7:30 a.m. I’ve tried taking melatonin and Benadryl, but they don’t have any effect. If I fall asleep so easily, the question of why don’t I just get into bed at a “reasonable” hour is one that plagues me. I just can’t seem to change the habit, even though I really want to. I’m going to try setting a light on a timer next to my bed at the survey’s recommended time of 6:45 a.m. But with my additional habit of pushing past my sleepiness in the evening, will this help?

Definitely worth a try, since by resetting your internal clock earlier with the light, you are less likely to want to stay up late. Keep in mind, though, that the intensity of the light you use at 6:45 a.m. is an important factor that may require adjustment during your trial. Although ordinary bedroom lamps might work for you, they might be insufficient.

I am considering using a light box to adjust my circadian rhythm, which is now severely delayed. I live in an apartment with large windows providing lots of daylight. At night, a nearby parking lot provides some light through my blinds. I recently bought a large sleep mask, as putting up blackout curtains could create problems with my landlord. Is my approach reasonable, or totally illogical?

To correct delayed sleep phase, there are two principles and procedures to keep in mind: (1) Restrict light exposure as much as possible in the evening and at night until about 1.5 hours before wake-up time. (If your wake-up time is in the mid- to late morning, minimizing light exposure will be important throughout early morning.) Before sleep, you want to turn down the lights to a comfortable level for reading or watching TV, but nothing more. During sleep, even low levels of light can be counterproductive, so consider adding dark curtains inside your blinds to block light from the parking lot. (2) Starting at wake-up time, or 1.5 hours earlier, you want to enhance light exposure to counteract your delayed rhythm. Since your bedroom will be dark, you cannot utilize light through the windows.

There are two complementary solutions: First, you can use a dawn simulator for 90 minutes before wake-up time, or simply an appliance timer to turn on bedroom lights. Second, 30 to 60 minutes of bright light box therapy will be helpful when you wake up–a good time for breakfast and reading the newspaper. Over a couple of weeks, move your wake-up time (and light exposure) gradually earlier–say, 15 minutes every three days. Before long, you can expect to normalize your delayed pattern.

Several of my siblings suffered with severe cases of infectious mononucleosis. They all experienced delayed sleep phase, but this symptom of mono seems to be absent from the medical literature! My siblings recovered normal sleep habits after their bouts with mono, but for myself, the delayed sleep phase problem has become chronic. Any comments and suggestions

Hypersomnia — abnormally long sleep — is common during the active phase of bacterial and viral infections. Delayed sleep phase is another matter: sleep duration is normal, or somewhat longer than normal, but both sleep onset and wake-up times are significantly later than normal. In such cases, light therapy starting at spontaneous (late) wake-up time, and edging earlier over days, may help to alleviate the sleep problem and also increase daytime energy. Once the infection has passed — as you have described for yourself — the prognosis of normalized sleep timing with light therapy is excellent. One caveat: during the active period of infection, the eyes may become hypersensitive to bright light, making the treatment difficult to tolerate. In such cases, dawn simulation may be the answer, but this has yet to be tested.