Can Coffee Make U Sleepy?

Caffeine can block the effects of adenosine, which is what makes you feel alert after your morning cup of joe. However, once the caffeine wears off, your body may experience a buildup of adenosine that hits you all at once, which is why coffee can make you feel tired.

Why do I feel sleepy after drinking coffee?

When caffeine binds to your adenosine receptors, your brain isn't processing its adenosine, but that doesn't mean it stops producing it. So once the caffeine wears off, there's a build-up of adenosine that will bind to your brain's receptors, making you feel tired.

Why does caffeine make you sleep?

Caffeine is a stimulant, and works by blocking adenosine from binding to its receptors. Adenosine is the chemical responsible for making us feel sleepy; it builds up over the course of the day, creating something called “sleep pressure,” which makes us tired and (hopefully) sends us to sleep.