Research

Hormonal

High-frequency low-dose caffeine administration (0.3 mg/kg/hour) effectively counteracts cognitive performance degradation and prevents accidental sleep onsets during extended wakefulness, particularly during the circadian performance nadir.

If you are facing a long shift or extended wakefulness, take small doses of caffeine (approx 0.3 mg per kg of body weight) every hour rather than one large dose. This strategy keeps your cognitive performance sharp and prevents accidental sleep, especially during your body's natural low-energy window (circadian nadir). Be aware that you might feel more subjectively sleepy than usual, but your objective performance will be protected.

GoodSupportsHIGH confidence
High-frequency low-dose caffeine administration is effective in countering the detrimental performance effects of extended wakefulness... Rising caffeine levels markedly attenuated wake-dependent deterioration of a number of measures of cognitive performance, particularly at the circadian performance nadir.
James K. Wyatt et al. · SLEEP · 2004

Why this rating

Double-blind, placebo-controlled, parallel-group design with a rigorous forced desynchrony paradigm separating circadian and homeostatic effects.

Source

Low-Dose Repeated Caffeine Administration for Circadian-Phase-Dependent Performance Degradation During Extended Wakefulness

James K. Wyatt et al. · SLEEP · 2004

DOI 10.1093/sleep/27.3.374

rct · n=16Cited 183×
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DOI resolved against Crossref · corpus check 2026-06-10

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