Adenosine: The Sleep Chemical That Makes You Tired After Being Awake
What Chemical in Your Brain Makes You Feel Tired After Being Awake?
Adenosine is the primary sleep-inducing chemical that accumulates in your brain during wakefulness and creates the biological drive to sleep. As you stay awake, adenosine levels steadily increase in key brain regions, particularly the basal forebrain, where it binds to receptors that promote sleepiness and inhibit wakefulness-promoting neurons. This adenosine accumulation represents the molecular basis of “Process S” (sleep homeostasis) in the two-process model of sleep regulation, explaining why you feel progressively more tired the longer you stay awake.