What Is Jet Lag?

By Brandon Peters, MD

Jet lag is a circadian disorder that transiently occurs after rapid travel across multiple time zones. It may be associated with other physical symptoms, including disturbed sleep. Learn about this common condition, its symptoms, and potential treatments.

If you have ever flown across a few time zones, you are undoubtedly familiar with the struggles of adjusting your sleep to the new hours. Why is jet lag, as it is called, so hard to tolerate and is there anything to be done?

First, it should be recognized that your body wishes to keep a regular sleep schedule. Certainly we are creatures of habit, and our bodies like when we go to bed and get up at the same time every day. Our biological clock, which is controlled by part of the brain called the suprachiasmatic nucleus, helps us to keep a regular schedule by releasing hormones on a regular pattern. This pattern is called a circadian—or “near day”—rhythm. Our sleep follows this same regular pattern.

When we disrupt the regularity of these cycles, our body treats us unkindly by making us sleepy or alert when we don’t wish to be. For example, if you were to go to bed three hours early tonight, you would have great difficulty falling asleep. However, if you fly from California to New York and crawl into bed at your normal bedtime, you are effectively attempting the same thing.

Causes

Rapid travel across multiple time zones leaves the circadian rhythms out of sync with the destination’s light-dark cycles. These rhythms affect sleep and wakefulness as well as metabolism, body temperature, and hormone release. It can take time for the internal circadian rhythm to be re-synchronized to external time cues. Jet lag is sometimes called desynchronosis, referring to the misaligned sense of time.

As a general rule, it is possible to adapt at an average rate of 1 hour per day. For someone who lives in California to fly to New York and cross three time zones, it would usually take 3 days to adjust to the new time zone. It is generally easier to travel westward and harder to travel eastward for most people.

Social jet lag may cause less intense symptoms and occurs in people who delay their bedtime and wake time by 1 to 2 hours on weekends and then have to correct as the work week resumes on Monday. This shift in the circadian timing may affect the start of the work week for several days.

Significance

In the new location, circadian signals may conflict with environmental and social cues in the context of jet lag. This may lead to a constellation of symptoms, including:

• Excessive daytime sleepiness

• Fatigue

• Insomnia

• Irritability

• Poor concentration

• Digestive problems (dyspepsia)

• Malaise (feeling unwell)

These symptoms may be disruptive and may be exacerbated by sleep deprivation, dehydration, sleep environment changes, and stress associated with travel.

Testing

The presence of the typical symptoms in the context of jet travel confirms the diagnosis without the need for further testing. In research, it is possible to measure an individual’s circadian pattern with tests that detect melatonin levels, often sampled from repeated saliva measurements. There are new blood tests also coming into clinical use that may identify the circadian rhythm.

Associated Conditions

Jet lag is most commonly associated with insomnia, defined as difficulty falling asleep or returning to sleep after waking. If insomnia occurs for less than 3 months, it is termed acute insomnia. As most people would be taking trips of a shorter duration than this, it could be grouped with other briefer disturbances of sleep. In some cases, jet lag may trigger a disruption that may evolve into a chronic form of insomnia.

Treatment

How can we counter our circadian rhythm when we travel? There are several techniques to reduce the effects of jet lag.

One solution would be to keep the same hours as our original time zone, going to bed and getting up based on the times at home.  his may not be the best way to enjoy our travels, especially if we fly great distances. An alternative would be to slowly adapt to the new time zone prior to leaving.

It may be possible to prepare the body gradually prior to departure by slowing adjusting bedtime and wake time to match the destination’s time. This can be done by adjusting our sleep by an hour for a week at a time. If we are crossing two time zones, the change can occur over two weeks. If traveling west, we would go to bed and get up an hour later for one full week. During the second week we would repeat the same, going to bed and getting up another hour later. If traveling east, we would go to bed and get up an hour earlier each week. If we can slowly adapt to the change, we will tolerate it better.  Unfortunately, unless the trip is quite lengthy, we wouldn’t be able to adjust the other way for our return home.This adjustment may be enhanced with properly time light exposure.

Light is one of the primary synchronizers of the circadian rhythm in sighted individuals. It may advance the timing of sleep earlier if the light exposure occurs in the 2 hours prior to the normal wake time or immediately upon awakening. Sunlight is best, but the use of light boxes or light therapy boxes may also have a role.

Beyond light, it may be important to address the symptoms that occur. Caffeine or strategic napping may relieve sleepiness. Other stimulant medications could also have a role. It may also be helpful to use hypnotic medications to aid sleep, including over-the-counter melatonin or prescription pills, such as:

• Zolpidem (Ambien)

• Eszopiclone (Lunesta)

• Zaleplon (Sonata)

• Ramelteon (Rozerem)

These medications to aid both wakefulness and sleep may ease the transition to a new time zone.

Conclusion

If you have a big trip coming up, you might plan ahead in how you can adjust your circadian pattern of sleep and wakefulness with some of the interventions outlined. This may help to optimize your experience while traveling to avoid the symptoms of jet lag.

Sources: 

Drake CL and Wright KP. Shift Work, Shift-Work Disorder, and Jet Lag. Principles and Practice of Sleep Medicine, 6thed., Philadelphia, Elsevier, 2017. pp.714-725.

American Academy of Sleep Medicine. International Classification of Sleep Disorders, 3rd ed. Darien, IL: American Academy of Sleep Medicine, 2014.

Gooley JJ. Treatment of circadian rhythm sleep disorders with light. Annals of the Academy of Medicine, Singapore. 37(8):669-76, 2008 Aug.

Sack RL. The pathophysiology of jet lag. Travel Medicine & Infectious Disease. 2009 Mar;7(2):102-10.

Sack RL. Circadian rhythm sleep disorders: part I, basic principles, shift work and jet lag disorders. Sleep. 30(11):1460-83, 2007 Nov 1.

Srinivasan V, et al. Jet lag: therapeutic use of melatonin and possible application of melatonin analogs. Travel Medicine & Infectious Disease. 6(1-2):17-28, 2008 Jan-Mar.

What to Take When You Can’t Sleep

A good night’s sleep is crucial for overall health and well-being, yet many individuals find themselves struggling with sleeplessness, whether due to stress, lifestyle factors, or underlying health conditions. While sleep problems can sometimes be temporary, persistent insomnia can lead to significant physical and mental health issues. If you’re having trouble sleeping, you may wonder what you can take to help fall asleep and improve your sleep quality. The answer depends on the underlying cause of your insomnia, and the options range from over-the-counter supplements to prescription medications. Below, we explore various remedies that can help when you can't sleep, both natural and pharmaceutical, and how to determine what might be best for you.

1. Over-the-Counter Sleep Aids

For many individuals, over-the-counter (OTC) sleep aids are a go-to solution when they struggle with occasional sleeplessness. These medications are typically sold without a prescription and contain ingredients designed to promote drowsiness or relaxation.

Diphenhydramine or Doxylamine

One of the most common OTC sleep aids is diphenhydramine, an antihistamine commonly found in medications like Benadryl and “PM” medications. Doxylamine is found in Unisom. Diphenhydramine and doxylamine work by blocking histamine receptors in the brain, which reduces wakefulness and promotes sleepiness. While it can be effective for occasional use, it’s important to note that this drug can cause grogginess the next morning, and repeated use may lead to tolerance, meaning its effectiveness diminishes over time. There is concern that long-term use may contribute to dementia risk.

Melatonin

Melatonin is a hormone that your body naturally produces to regulate the sleep-wake cycle. Supplementing with melatonin is a popular remedy for people who have difficulty falling asleep, particularly for those with circadian rhythm disorders or those who are adjusting to new time zones (like in the case of jet lag). Melatonin supplements are available in various doses, and they are generally considered safe for short-term use. However, it’s best to consult a healthcare professional about the right dosage and timing, as too much melatonin can actually disrupt your sleep cycle.

Valerian Root

Valerian root is a herbal supplement often used to treat insomnia and anxiety. It has sedative properties and may help some individuals fall asleep more quickly. The exact way it works is not fully understood, but it is believed to increase the amount of gamma-aminobutyric acid (GABA) in the brain, which promotes relaxation and sleep. While valerian root is generally considered safe for short-term use, it can cause side effects such as headaches or dizziness in some individuals. It’s advisable to use it under the guidance of a healthcare provider.

2. Prescription Sleep Medications

If OTC options do not provide the relief you need, prescription medications might be an option. However, these medications are usually prescribed for individuals who have chronic insomnia or other sleep disorders. Prescription sleep aids should only be used under the supervision of a doctor because they may cause side effects, interactions with other medications, and potential dependency.

Benzodiazepines

Benzodiazepines, such as temazepam (Restoril), lorazepam (Ativan), and alprazolam (Xanax), are often prescribed for short-term insomnia. These medications work by enhancing the effects of GABA, a neurotransmitter that calms brain activity and induces sleep. While they are effective, they are typically not recommended for long-term use due to their potential for dependence and withdrawal symptoms. Benzodiazepines can also cause side effects like dizziness, memory issues and dementia, and daytime drowsiness.

Non-Benzodiazepine Sedatives

Non-benzodiazepine sleep aids, such as zolpidem (Ambien) and eszopiclone (Lunesta), are commonly prescribed to treat insomnia. These medications have a similar effect to benzodiazepines but are often considered to be less habit-forming. Non-benzodiazepines work by targeting the brain’s receptors responsible for sleep and can help people fall asleep more quickly and stay asleep throughout the night. However, like benzodiazepines, they can cause drowsiness the next day, memory impairment, sleep-related behaviors, and have the potential for misuse.

Antidepressants

Certain antidepressants, like trazodone (Desyrel) and amitriptyline (Elavil), are sometimes prescribed off-label to help with sleep. These medications have sedative effects and are often used for individuals who experience insomnia due to anxiety or depression. They are generally considered safe for long-term use, but side effects can include daytime grogginess, dizziness, and weight gain. Additionally, these medications can interact with other antidepressants and should only be used under a doctor’s supervision.

3. Natural and Herbal Remedies

For those who prefer natural approaches, there are several herbal remedies and lifestyle changes that may help promote relaxation and improve sleep. While the evidence for these remedies varies, many people find them helpful for reducing stress and encouraging restful sleep.

Lavender

Lavender is a widely used herb known for its calming and relaxing properties. Studies have shown that lavender can help reduce anxiety, stress, and insomnia. You can use lavender in various forms, such as essential oils, teas, or supplements. Diffusing lavender oil in your bedroom before bed or adding a few drops to your pillow can create a soothing environment that promotes better sleep.

Chamomile

Chamomile is another herb commonly used to improve sleep quality. It has mild sedative effects and is often consumed as a tea before bed. Chamomile has been used for centuries to treat anxiety and insomnia, and it may help calm the nervous system, making it easier to relax and fall asleep. While it is generally considered safe, some people may experience allergic reactions, particularly those who are allergic to ragweed or daisies.

Magnesium

Magnesium is a mineral that plays a vital role in many bodily functions, including muscle relaxation and sleep regulation. Studies have shown that magnesium supplementation may help improve sleep quality, especially for those with low magnesium levels. Magnesium can be found in foods like leafy greens, nuts, and seeds, or it can be taken as a supplement. Some people prefer magnesium supplements or magnesium oil for topical use to promote relaxation before bedtime.

4. Lifestyle and Behavioral Changes

Sometimes, sleep difficulties are not solely resolved by taking medication or supplements. Lifestyle changes and good sleep hygiene can have a significant impact on improving your sleep quality in the long term. A few strategies to consider include:

• Establishing a consistent bedtime routine: Going to bed and waking up at the same time every day helps regulate your body’s internal clock.

• Creating a calming environment: Keeping your bedroom cool, dark, and quiet can help signal to your body that it’s time to sleep.

• Limiting caffeine and alcohol: Both caffeine and alcohol can disrupt your sleep patterns, so try to avoid consuming them several hours before bed.

• Managing stress: Practicing relaxation techniques such as meditation, deep breathing, or gentle stretching before bed can help reduce stress and anxiety, making it easier to fall asleep.

5. When to See a Doctor

If you’ve tried over-the-counter remedies, herbal supplements, and lifestyle changes without success, it may be time to consult a doctor. Persistent sleep problems could be indicative of an underlying condition, such as sleep apnea, restless leg syndrome, anxiety, or depression. A healthcare provider can help determine the root cause of your sleep difficulties and provide more targeted treatment options. Cognitive behavioral therapy for insomnia (CBTI) is the preferred treatment for insomnia that persists beyond 3 months.

Conclusion

There are a variety of options to consider when you can’t sleep, ranging from over-the-counter supplements to prescription medications and natural remedies. What you choose to take depends on your individual circumstances, including the underlying cause of your sleep issues. While medications can provide short-term relief, incorporating lifestyle changes and improving sleep hygiene may offer long-lasting benefits for your sleep quality. Ultimately, if sleeplessness persists, it’s important to seek professional advice to address any potential underlying health concerns.

This article was created using OpenAI’s ChatGPT on February 21, 2025 and it was personally reviewed and edited by Brandon Peters, M.D. to ensure its accuracy. This use of augmented intelligence in this way allows the creation of health information that can be trusted.