CIRCADIANSTACK·v1.2
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PILLAR · Edge Cases

Jet lag protocol: east vs west

Two Protocol cards for directional travel. Eastbound = phase advance. Westbound = phase delay. Melatonin at 0.3-0.5mg, light exposure windows, pre-flight prep.

By The CircadianStack Editorial Team
Editorial · Chronobiology desk
Reviewed by Dr. Iris Chen, MD, Sleep MedicineCredential verification pending
PUBLISHED 2026-04-21REVIEWED 2026-04-2114 MIN

Two Protocol cards for directional travel. Eastbound = phase advance. Westbound = phase delay. Melatonin at 0.3-0.5mg, light exposure windows, pre-flight prep.

QUESTIONS

Questions logged on this protocol

Q01

Why is eastbound harder than westbound?

The human circadian period is slightly longer than 24 hours; Czeisler et al. 1999 (Science) measured a mean of ~24.18 hours in healthy adults. Delaying phase (westbound) aligns with that natural drift; advancing phase (eastbound) fights it. The practical effect: most travelers adapt ~1 hour per day eastbound and ~1.5 hours per day westbound. A six-zone eastbound trip takes roughly a week to fully re-entrain without intervention.

Q02

What melatonin dose and when?

0.3-0.5mg, taken 5 hours before target sleep onset at destination. Herxheimer & Petrie 2002 (Cochrane Database) reviewed 10 trials and found consistent benefit for eastward travel across 5+ time zones. Higher doses (3-10mg sold at retail) produce more sedation but no greater phase-shift per Brzezinski et al. 2005 (Sleep Med Rev). Timing matters more than dose: take it too early and you delay phase in the wrong direction.

Q03

Should I pre-shift before the flight?

For trips of 4+ time zones, yes. Eastman & Burgess 2009 (Sleep Med Clin) recommend shifting sleep onset 1 hour earlier per day for 2-3 days pre-flight (eastbound) or 1 hour later (westbound), paired with morning light (east) or evening light (west). Travelers who pre-shift land already partially entrained and cut recovery time in half.

Q04

What about short trips of 1-2 nights?

Don't re-entrain. Stay on home time for sleep as much as destination logistics allow. Full circadian shift takes days you don't have; chasing it leaves you dysregulated both directions. Keep meals and caffeine on a home-time schedule, and use melatonin only if you must sleep at an unfamiliar clock time at destination.

Q05

Does alcohol on the plane help or hurt?

Hurts. Alcohol suppresses REM sleep in the first half of the night and is associated with fragmented sleep architecture (Ebrahim et al. 2013, Alcohol Clin Exp Res). Cabin altitude already reduces blood oxygen saturation; adding alcohol compounds the effect. Hydrate, skip the wine, time sleep to the destination clock if the flight is long enough.

Q06

Can children use this protocol?

The light exposure parts (morning light east, evening light west) apply at any age. Melatonin in children is off-label; AASM and most pediatric sleep specialists recommend against routine use without a clinician's supervision. For kids, focus on light timing, meal timing, and strict destination-schedule bedtime from night one.

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