Background

Jetlag is also referred to as jet lag disorder which is a type of sleep disorder that is characterized by a condition that affects a person who travels across several time zones within a short period of time. This affects the circadian rhythm, a natural biological clock of the body that shows the time for sleep and wakefulness. 

A circadian rhythm is the cycle that lasts for 24 hours, during which many physiological functions occur, such as sleep, secretion of hormones, and regulation of body temperature. This internal clock is synchronized with the external environment, majorly dependent on light and darkness. Jetlag occurs when a person moves from one time zone to another, and the external environment doesn’t correspond to this body clock. 

Epidemiology

At present, researchers have not determined the actual rate of occurrence of jet lag. Nonetheless, cross sectional surveys of international business travelers suggest that nearly 70 percent of them confirmed fairing often/always affected by jet lag. The role of age and sex in the incidence of jet lag still remains inconclusive but data indicated that older adults may less likely to be troubled by symptoms of jet lag. 

Anatomy

Pathophysiology

Circadian Rhythm Disruption 

• Suprachiasmatic Nucleus (SCN): The SCN is connected to the ganglion cells in the retina and plays the role of synchronizing the sleep-wake period according to the light or darkness in the environment. Jet lag disrupts synchronization between the SCN and the external environment because of quick transition through several time zones. 
• Light Exposure: In mammals, light is the dominating synchronizer, or in other words a cue used to synchronize the circadian rhythm. These changes position also rely on light exposure at the correct time and even overcrowding the sensitive nerves and cells in the nodes. For instance, when travelling east and getting to bed soon after sunset, this will take time before the body adapts to the new time zone. 

Hormonal Changes 

• Melatonin: This hormone is secreted from pineal gland, and it is involved in the regulation of sleep and wakefulness. Usually, melatonin levels increase at sunset and increases during the night to aid in the sleeping process and decrease during the morning. This annual cycle is disturbed by jet lag resulting in inability to either sleep or wake up at the correct time in response to the new location. 
• Cortisol: Another hormone that is regulated by the biological clock is cortisol; it is gradually raised during the night and reaches it maximum level in the early morning before slowly declining thereafter. Any break of this cyclic manner may result in manifestations of fatigue and cognitive dysfunction. 

Etiology

Some of the reasons include the direction of travel (eastward direction usually results to worst jet lag), shift in photoperiod, melatonin and cortisol rhythms. Age is another cause that determines the degree and duration of jet lag and other factors such as genetics, and the overall health of an individual. Other factors including dehydration while on board flights, cabin pressure, and poor sleeping habits worsen the condition thus making it difficult for the traveler to adapt to the new time difference. 

Genetics

Prognostic Factors

Jet lag is mainly experienced at the time of travel and can go on for 4 to 6 days as the body adapts to the local circadian rhythm. Adjustment period also depends on the number of time zones, and the more the numbers of time zones that have been crossed, the long the period that is usually taken to adjust. 

Clinical History

Age Group 

Both children and adults experience jetlag though its intensity and the rate it is processed may differ. Older Adults suffer from more severe symptoms and require time to adapt more so because their circadian rhythms might be slower to adapt or due to other age related factors. 

Physical Examination

General Appearance 

• Alertness and Orientation: Evaluate patient’s mental status, specifically their consciousness, ability to find own location and time. 
• Fatigue: For physical exhaustion, one needs to identify symptoms of drowsiness as may be evident in low energy levels, and an ability to hardly keep the eyes open. 

Vital Signs 

• Blood Pressure and Heart Rate: Take the patient’s blood pressure and pulse to eliminate any cardiovascular problems that can mask or worsen the effects of jet lag. 
• Respiratory Rate: Assess for the appropriateness of the respiratory rate and the effort being put in by the patient. 

Neurological Examination 

• Cognitive Function: Assess cognitive health through some simple quizzes involving memory, concentration and attention span. 
• Reflexes and Coordination: It is essential to examine reflexes and coordination to rule out any neurological disorders. 

Mental Status 

• Mood and Affect: Inquire the patient general wellbeing and look out for signs of irritability, anxiousness, or depression. 
• Sleep Patterns: Ask about the challenges with sleep, to include; difficulty in falling asleep, staying asleep and establishing if one is sleepy during the day. 

Age group

Associated comorbidity

Frequent Travelers 

Sleep Disorders 

Mental Health Conditions 

Associated activity

Immediate Onset: It is said that symptoms normally develop shortly after entering the new time zone. 

Duration: Symptoms may vary from several days to one and a half to weeks if need be, depending on the number of time zones crossed and the ability of an individual to recover from the effects of journey. 

Acuity of presentation

Differential Diagnoses

• Insomnia 
• Sleep apnea 
• Depression 
• Hypothyroidism 
• Diabetes Mellitus 
• Adrenal Insufficiency 
• Myocardial infarction 

Laboratory Studies

Imaging Studies

Procedures

Histologic Findings

Staging

Treatment Paradigm

Non-Pharmacological Approaches 

• Pre-Travel Adjustments 
• Post-Arrival Strategies 
• Sleep Hygiene 
• Diet and Exercise 

Pharmaceutical Agents 

Chronobiotics: 

• Melatonin: Regularizes the body clock; taken in the morning for westbound travel and in the evening for eastbound travel. 
• Hydrocortisone: Imitates the cortisol elevation in the morning, may help with the circadian shift; standard dosage is 20 mg. 

Hypnotics: 

• Temazepam: Aids in falling asleep and staying asleep; should be taken half an hour to an hour before going to bed. 
• Triazolam: Rapid onset for sleep; should be taken before going to sleep a time. 
• Diazepam: For sleeping and anxiety; it has a comparatively longer half-life thus not as effective for jet lag. 
• Lorazepam: Helps with getting to sleep and with stress; capsules are to be ingested before sleep. 
• Chlordiazepoxide: For anxiety disorder and could help sleep; take at night. 

Non-Benzodiazepine Z-Drugs: 

• Zaleplon: Reduced aspects of next-day sleepiness; onset of sleep is fast, and half-life is short. 
• Zolpidem: Indicated for both falling asleep and staying asleep; administered 30 minutes prior to the time the patient wishes to fall asleep. 

Stimulants: 

• Caffeine: Improves wakefulness; should not be used often. 
• Armodafinil: Antioxidant and Promotes wakefulness and cognitive function; preferably taken in the morning. 

Interventions 

• Light Therapy: Subsequently, the chronotype is shifted with the help of bright light exposure. It is used while traveling towards the east in the morning and towards the west in the evening; it includes the sessions of about 20-30 minutes. 
• Chronotherapy: It is recommended to slowly adjust the sleep-wake pattern to that of the destination before starting a trip. Continue adjustment post-travel. 

Phased Management 

• Pre-Trip: Allow the sleep-wake cycle, and exposure to environmental light to vary and synchronize with the new time at the intended destination. 
• During Travel: Do not consume alcohol and caffeine, get enough sufficient water intake, and control the room where you sleep. 
• Post-Arrival: Set your clock and watches immediately to local time, get as close to natural light as possible, and try to keep the same bedtime and wake up time as much as possible. 

by Stage

by Modality

Chemotherapy

Radiation Therapy

Surgical Interventions

Hormone Therapy

Immunotherapy

Hyperthermia

Photodynamic Therapy

Stem Cell Transplant

Targeted Therapy

Palliative Care

use-of-a-non-pharmacological-approach-for-treating-jet-lag

• Pre-Travel Adjustments: Naturally, make changes in the sleep-wake schedule in the days before travel to align the circadian rhythms with the preferred time zone. Reschedule your activities for at least half an hour or an hour earlier or later in the day. Take more outer light in the morning if going east or in the evening if moving toward west. This assists in gradually aligning the circadian rhythm in the right direction. 
• During Travel: Remember to take enough water as this will help to hydrate you throughout the exercise. Eliminate caffeine and alcohol products or limit their intake because they interfere with the quality of sleep which is essential in minimizing jet lag. Eyes covers such as eye masks, ear plugs, noise reducing headphones can also be effectively used to enhance comfort in the plane during the journey.  
• Post-Arrival Strategies: Whenever arriving, start to adapt to the local timetable for eating, sleeping and waking up as well as other activities. If it is not according to the local time, try as much as possible not to fold sleeping in the afternoon. Ensure that you adhere to the recommended bedtime from the airport and stay away from caffeine products. Sleep at night and wake up in the morning at a given standard time.  
• Sleep Hygiene: Make sure your environment is cool, dark and free from all forms of noise that can disrupt your sleep. If it is light, try using a curtain, blind or a mask for the eyes and for noise try using a fan or a comfortable sounds machine if necessary. Use deep breathing, meditation, or progressive muscle relaxation to facilitate your sleep since they assist you in finding sleep quickly. 
• Diet and Exercise: Exercise is an important facet in the daily lifestyle. Flexibility relates to controlling sleep and the levels of wakefulness. However, it is important to stay away from rigorous activities in the evening before going to bed. Take meals in proper proportion at the correct time in relation to the new time zone. Do not consume meals that contain a lot of food or are densely packed before sleeping, as they interfere with sleep. 

Role of Chronobiotics

• Melatonin: It is available in different dosages starting from 0.5 to 5 mg and can influence the circadian rhythms; it is available in mouth dissolving tablets, sublingual, and transdermal patch form. The exact time at which melatonin is given to support circadian shift is not straightforward and depends on the individual’s circadian chronotype and their response to the phase shift. Overall, melatonin should be consumed in the morning when going to the Western side of the globe or in the evening when moving to the eastern part of the world. 
• Hydrocortisone: Hydrocortisone may assist in shifting the circadian rhythms as it replicates the natural cortisol surge experienced in the morning. This can possibly help to recognise the internal body clock to adjust to the new time adopted in the new zone. An average dose which has been used in studies is the 20 mg of hydrocortisone. 

Role of Hypnotics

Temazepam: It is typically administered to assist the patient to fall asleep and to maintain the sleep. This is efficient in treating insomnia that results from jet lag. Such products are usually taken in the form of pills or capsules, and used before sleep, usually 30 minutes to 1 hour before sleep. Initiates and maintains sleep, which provides an excellent opportunity to switch from one time zone to another. 

Triazolam (0. 125 mg to 0. 25 mg): It is a benzodiazepine that serves as a rapid-acting hypnotic action for treating sleep onset issues. Possible to take in capsule or tablet form and should be taken before going to sleep. Effective in helping achieve a fast fall asleep, that might be helpful when coping with sleep disturbances due to shift changes, jet lag, etc. While it is useful in inducing sleep, it has a short half-life and may also cause wakefulness during the night. 

Diazepam (5 mg to 25 mg): It is a benzodiazepine which may be administered for the control of anxiety, in muscle relaxation besides in treating sleep disorders. Usually available in capsule form, which has to be consumed on an empty stomach, 30 minutes before the intended sleeping time. Used to treat jet lag, it can improve sleep but is not often used as a single treatment for jet lag because of its long half-life and residual effects in the morning. 

Lorazepam (0. 5 mg to 1 mg): It is prescribed for the cases of anxiety disorders and for sleep disorders as well. However, for helping with the onset of sleep and alleviating jet lag problems, it can be highly useful. Taken orally before bedtime. These effects may help to cope with sleep disturbances connected with jet lag but its ability to help one get to sleep also signifies that it may help to decrease anxiety. 

Chlordiazepoxide (5 mg to 25 mg): It is mainly applied for anxiety and withdrawal syndrome and may also be helpful for sleep. Usually in tablet or capsule form and are often taken orally just before going to sleep. 

Non-Benzodiazepine Z-Drugs 

• Zaleplon (5 mg to 10 mg): This is an anxiolytic and anticonvulsant medication that is fast acting both in onset of sleep and in relaxation. When taken orally, the capsule must be consumed before going to sleep. Helpful when a person wants to fall asleep as fast as possible. It has a short half-life meaning that patients using the product will not experience extreme drowsiness the following day. 
• Zolpidem (5 mg to 10 mg): These include insomnia, which is classically used in the treatment of sleep onset and in the maintenance of sleep. Swallowed whole as a tablet with half a glass of water before ingestion and put to sleep 30 minutes before going to bed. 

Role of Stimulants

• Caffeine: This is a CNS stimulant that inhibits the action of adenosine, thus improving wakefulness and alertness. Occasionally used in products such as coffee or tea, energy drinks or in the form of tablets. 
• Armodafinil: Is a dopaminergic agent, which means it increases the levels of the neurotransmitter dopamine in the brain, promoting wakefulness and improved brain function. Usually, these tablets are ingested orally with water preferably in the morning. 

use-of-intervention-with-a-procedure-in-treating-jet-lag

Light Therapy 

Bright light exposure refers to controlling light exposure at various parts of the day with the aim of realigning one’s body clock. Current studies also show that it may either promote or suspend the sleep-wake schedule depending on when light exposure is done. It mainly utilizes a light box that radiates light of high intensity of up to 10,000 lux which is normally recommended. This treatment should be carried out in the morning when heading eastwards to phase advance the sleep wake schedule or in the evening when going westwards to phase delay the schedule. 

Procedure 

Hence light exposure for eastward travel should be in the morning, while for westward travel should be in the evening. Such meetings usually take 20 to 30 minutes of time. Bright light can be used to manipulate the chronobiological clock and alleviate the signs of jet lag. Ideally, it is applied several days prior to traveling and for several days after it is over. 

Chronotherapy 

It requires the slow shift in the sleep-wake schedule to be closer to the time of the location one is traveling to. It is useful in phase shifting and it does that in a gradual manner. 

Procedure 

Sleep at night and wake up in the morning fifteen to thirty minutes earlier or later every several days to adapt to the new time. 

Probably, changes should be made several days before a trip and continue until the new schedule is established. 

use-of-phases-in-managing-jet-lag

Managing jet lag effectively involves a phased approach: before the trip, it is recommended to act gradually in relation to the time of sleep and increase the amount of time spent in conditions with natural light corresponding to the time zone of the planned trip. When traveling avoid alcohol and caffeine and make sure you are taking enough water. Upon arrival, it is crucial immediately adjust to the local rhythm, go out to get some sunlight so that the body would know the new time, and sleep for short intervals. Staying on a daily wake- sleep cycle and keeping the sleep environment proper also contribute towards eradicating jet lag and adapting into the new zonal time. 

Medication

Future Trends

Media Gallary

References

Approaches to the Pharmacological Management of Jet Lag – PMC (nih.gov) 

Pharmacological interventions for jet lag  – PMC (nih.gov) 

Jet Lag – PMC (nih.gov) 

Jet lag: Heuristics and therapeutics – PMC (nih.gov)