After 21 hours without sleep, taking 0.35 grams of creatine per kilogram of body weight increases the ratio of creatine to N-acetyl-aspartate in a specific region of the brain by up to 6.1%, suggesting that sleep deprivation may temporarily allow more creatine to enter brain cells than under normal conditions.

During sleep deprivation, taking more creatine (0.35 g/kg) leads to slightly better cognitive performance than taking less (0.2 g/kg), but the benefit does not increase beyond a certain dose, suggesting the brain reaches a limit in how much creatine it can use under these conditions.

Taking 0.2 grams of creatine monohydrate per kilogram of body weight as a single oral dose can reduce the decline in cognitive functions such as logical reasoning, numerical processing, language speed, and attention during 21 hours without sleep in healthy young adults.

Taking a specific dose of creatine while sleep-deprived is linked to a measurable drop in ATP-β levels in the brain, along with faster thinking and less tiredness.

Taking a specific dose of creatine monohydrate by mouth during a night of little sleep may help maintain faster thinking in language, logic, and math tasks, reduce feelings of tiredness, and help preserve normal energy-related chemistry in the brain.

Taking creatine supplements can slightly boost the amount of creatine in your brain—by about 3 to 10%—but not as much as it boosts your muscles, probably because your brain is harder to reach with supplements and makes some creatine on its own.