The Physiological Reason Some People Fall Asleep After Drinking Coffee

Some people use it as a pick me up. Others use it when they need a nap.

coffee, sleepy, adhd Valentyn Volkov and Cookie Studio / Shutterstock 

Many of us rely on caffeinated drinks just to make it through the morning. An estimated 75% of American adults drink coffee with around 50% consuming it on a daily basis. For some people, caffeine energizes them and makes them alert throughout the day. However, others may find that drinking coffee seems to have the opposite effect on them, and they may find themselves falling asleep at their desks instead of rapidly getting through their tasks. 


There is significant physiological reasoning behind why caffeine has a paradoxical effect on those primarily with ADHD. 

People with ADHD may find themselves sleepy after consuming coffee since the stimulants in caffeine finally relax their brains. 

ADHD (Attention Deficit Hyperactivity Disorder) is a condition that often begins in childhood and persists into adulthood. Symptoms can include the inability to focus on tasks, constant fidgeting, and difficulties sleeping. 

In the United States, about 4.4% of adults have ADHD. Some of these adults may assume that consuming caffeine will keep them alert and focused on tasks.


However, one professor on TikTok explained why caffeine may have the complete opposite effect on those with ADHD. 

According to Neurodivergent Coach Pasha Marlowe, stimulants, including Adderall and caffeine, provide a sense of calmness for those with ADHD instead of alertness. 

“Our baseline is chaos,” Marlowe said of those with ADHD in a TikTok video. “Ruminating thoughts and intrusive thoughts, that’s our baseline. So the coffee and the stimulant is just bringing us up to a place of somewhat stability, so finally, our brains can relax.” 



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“Finally, we might be able to rest our head on the couch post-coffee and stimulant, and take a moment to breathe and sleep.” 

Other TikTok users with ADHD proved Marlowe’s statements as true, with some of them sharing that coffee makes them feel tired and ready for a nap, rather than peppy and ready to take on the day. 



According to scientists, when caffeine is consumed, it interacts with a molecule in the body known as adenosine, which assists with communication between brain cells and acts as a nervous system depressant. Throughout the day, adenosine levels are supposed to increase and make one feel drowsy. 


However, caffeine interferes with that process, and counteracts with adenosine levels, instead promoting alertness and energization. 

For people who do not have ADHD, increased consumption of caffeine can make them feel more awake since their brain activity is amped up. Although, those who have ADHD and do not have normal levels of brain activity may find that with caffeine, levels of hyperactivity reduce all of the buzzing thoughts in their head suddenly cease, and they may feel a sense of calmness and drowsiness. 

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People also may find that caffeine helps them with their ADHD symptoms. 

This is not always a bad thing. Some people with ADHD may use caffeine as a means to alleviate their symptoms and allow them to calm themselves, especially those who find that stimulant medications such as Aderol do not seem to be much help to them. 


Caffeine has been proven to help with the distractibility that comes with ADHD in some people. A study that explored the use of caffeine pills in U.S. Army soldiers with ADHD found that the stimulant helped them keep their attention on repetitive work, complete tasks faster, and reduced impulsivity. 

It is important to note that there may be other reasons besides ADHD that people feel sleepy after drinking coffee. It can range anywhere from genetics that makes one resistant to the effects of caffeine, to a high tolerance for caffeine, or not having enough caffeine. 

While caffeine can have various effects on different people, it is not healthy to overindulge in caffeine. The recommended daily amount for healthy adults is 400 milligrams. 


Whether it is to help you stay awake during a long day or to help you get some sleep and calm your nerves, caffeine always tastes good with a splash of milk, sugar, and even whipped cream! Luckily, it is readily available near you in coffee shops, cafes, and some gas stations. 

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Megan Quinn is a writer at YourTango who covers entertainment and news, self, love, and relationships.