Updated at: 08-07-2022 - By: Jane

At the very least, one of your prescriptions may not have worked as intended if you’re taking many medications. Your doctor may have given a different medication in this circumstance.

What could possibly be wrong with taking a drug prescribed to you by your doctor? Quite simply, this is due to the fact that each person’s physique is unique. A drug’s effects aren’t felt by everyone in the same manner.

Just think about how your pals could react to drink or pot if you’re not sure about this.

In addition to marijuana, caffeine qualifies as a drug under federal law. Actually, it is the world’s most widely used psychoactive substance. Caffeine affects people differently, but this is true of all substances.

Caffeine gives a rapid boost for most of us, whether it’s in the form of coffee, soda, or an energy drink. Caffeine, on the other hand, may cause drowsiness rather than vigilance in certain people.

What is the mechanism by which caffeinated beverages deplete your energy stores? Yes, but isn’t it also a stimulant?

Yes, it is correct. However, there could be other factors at play.

What Caffeine Does In the Body

The most common responses to the question of what caffeine does are variations on the themes of “it wakes you up,” “it increases your alertness,” or “it gives you more energy.”

However, those are the effects of caffeine. Here’s what it is: a central nervous system stimulant.

Caffeine Makes Me Tired, So I Asked a Sleep Expert to Explain Why - PureWow

Almost all of the caffeine we ingest comes from plants like the coffee plant (which produces coffee beans), the tea plant, or the cacao plant (which produces the cocoa beans used to make chocolate).

Nevertheless, some of the caffeine today consumed in beverages such as soda and energy drinks has been synthesized by humans. There are no chemical differences between natural and synthetic forms of caffeine, therefore they all have the same effect.

You don’t need a “magic ingredient” to get the energy boost that coffee is known for. Caffeine, like all other stimulants, has a unique way of interacting with the brain’s neurotransmitters. Adenosine is the most crucial molecule in this scenario.

A1 Adenosine Receptors

Adenosine molecules are produced by the body throughout the day. More of them are produced each hour while we are engaged in any form of physical or mental exercise.

Sleep deprivation and the urge to rest are both conveyed by adenosine, which functions as a neurotransmitter in the brain. The body’s adenosine levels keep rising throughout the day, which is why we become more and more fatigued.

Adenosine sends signals to the brain by attaching to receptor groups known as adenosine receptors. Muscle relaxation and sleepiness are promoted by sending messages throughout the brain and body once adenosine has locked onto some of them. That’s a natural aspect of the sleep-wake cycle for most people.

Caffeine, on the other hand, can stop those “tiredness” messages from being delivered.

Caffeine is similar to adenosine in its ability to act, but it serves a different function. It binds to and inhibits the A1 receptors. Because of this, they cannot receive the “you’re going tired” message from adenosine.

The stimulant, on the other hand, keeps you awake until the caffeine wears off. That’s why a cup of coffee and a 5-Hour Energy only keep you energized for a few hours, respectively.

A2A Adenosine Receptors

Brain A2A receptors are also activated by adenosine.

A2A receptors, unlike A1 receptors, do not play a role in fatigue. They regulate the release of feel-good hormones and neurotransmitters, such as serotonin and dopamine, in the brain. Adrenaline, the so-called “fight-or-flight” hormone, is likewise moderated by these supplements.

Caffeine acts as a stimulant, causing the release of serotonin, dopamine, and adrenaline in the brain. Adenisone is blocked from binding to the A2A receptors by coffee, allowing the surge of brain chemicals to flow freely.

Caffeine in coffee or an energy drink is what gives us a short-term lift.

It’s not simply that the hormones and neurotransmitters it releases give us a boost of energy and happiness. In the short term, caffeine blocks adenosine receptors, preventing the peptide from binding to them.

Blood Vessels

Caffeine’s final vital role may seem to contradict what you’ve previously been informed.

Caffeine has been shown in several studies to expand blood arteries and enhance blood flow. One of the reasons doctors think coffee is helpful for your heart health is because of the apparent vasodilation.

The brain, on the other hand, operates in a very unique manner. Coffee acts as a vasoconstrictor, causing blood vessels to constrict and decreasing blood flow, which is exactly what caffeine does. What could be the reason behind this?

The A2A receptors, longtime buddies of ours, are to blame.

Blood arteries enlarge as adenosine attaches to them, allowing for enhanced blood flow. Those receptors are obstructed by coffee, which causes the blood arteries to constrict rather than expand.

In many cases, a headache is brought on by the expansion of blood vessels in the brain, which puts pressure on nearby sensitive nerves. Caffeine relaxes the arteries, reducing the strain on the nerves, which is why it can be used to treat headaches.

Why Does Coffee Make Me Tired?

Caffeine in coffee is commonly thought of as a wake-up drink, but studies show that it may really have the opposite effect. Take a look at the following reasons why coffee might be making you tired.

1. Caffeine Can Affect Stress

Caffeine raises levels of cortisol, sometimes known as the stress hormone. When your cortisol levels rise, you may experience anxiety and stress, which may cause you to lose sleep.

Despite the fact that anxiety and tension might make you feel more awake in the moment, they can lead to feelings of exhaustion later in the day. Try the military approach or the 4-7-8 method if you’re having a hard time falling asleep at night because of your tension.

2. Coffee Blocks the Effects of Adenosine

The sleep-inducing chemical adenosine is synthesized by your body. Caffeine in coffee is absorbed by the body and, once reaching the brain, binds to adenosine receptors.

This wake-me-up feeling you get from your morning cup of joe is due to an amino acid called adenosine, which caffeine blocks. When the caffeine wears off, your body may experience an accumulation of adenosine, which can make you feel fatigued all at once.

Why should you avoid coffee on an empty stomach - Times of India

3. You May Have a Caffeine Tolerance

Tolerance to caffeine might develop over time if you drink it on a frequent basis. To counteract the effects of caffeine, your body may begin to produce more adenosine receptors, since caffeine works by suppressing the effects of adenosine.

If your body develops more adenosine receptors, your daily cup of coffee may not provide as much of a pick-me-up as it used to in the past. There are a few studies who feel that long-term exposure to caffeine has no effect on the body’s ability to break down the stimulant.

4. Sweetener Can Increase Blood Sugar

If you’re adding sweets to your coffee, you may want to look into it as a possible cause. Instead of a coffee crash, sugar, syrup, and honey may cause a sugar collapse.

Sugar in your coffee can cause an increase in insulin production in people who aren’t acclimated to it. This could result in a classic sugar crash due to a decline in blood glucose levels.

In order to determine whether sugar is the real cause in your inability to stay awake after your morning cup of coffee, you may want to try removing the extra sweets from your drink.

5. The Dairy Is Affecting You

Tryptophan, an amino acid found in dairy, has been linked to a better night’s sleep. In the evening, this is a wonderful way to unwind, but in the morning, it may be detrimental.

While tryptophan can make you sleepy, milk only contains a small amount of it, so it’s unlikely that a modest amount of dairy in your coffee will make you weary.

As long as the plant-based substitute to dairy in your morning cup of joe makes you more alert, it may be time to give up the A.M. dairy consumption.

6. Caffeine Can Be a Diuretic

If so, have you ever noticed an increase in the frequency of your restroom breaks after consuming caffeine? If that’s the case, it’s probably because caffeine is a diuretic, which means it helps flush out water and salt from your body.

Dehydration can set very quickly if you have a cup of coffee without first replenishing your fluids.

  • Fatigue
  • Dizziness
  • Confusion
  • Thirst
  • The skin and mouth are parched.

Make sure you’re drinking enough water with your morning cup of joe to avoid dehydration. In order to be well hydrated, the Mayo Clinic recommends that individuals consume 92 to 124 ounces of water daily.

7. There’s Mold in Your Coffee

As disgusting as mold in your coffee is, the contamination that mold causes may be contributing to your sleepiness. Mycotoxins, a form of mold that has been related to persistent weariness, have been found in some coffee beans.

Mold in your coffee might have far-reaching implications that go beyond simple tiredness. As a result of these studies, mycotoxins have been classed as potentially carcinogenic to humans.

How To Minimize the Side Effects of Caffeine

If you wish to avoid the negative effects of coffee without giving it up all of its benefits, the following suggestions can help:

  • The FDA recommended a daily maximum of 400 milligrams of caffeine for most adults, which is the equivalent of two 16-ounce cups of coffee.
  • Avoid sugary drinks since they may cause an increase in your blood sugar, resulting in a sugar crash. In order to avoid the caffeine crash, try reducing the sweetness of your caffeinated beverages.
  • Caffeine can be a diuretic, so it’s important to drink enough of water while you’re using it. A 16-ounce glass of water every four hours or at least 8 ounces of water every two hours is what you should be striving for.
  • Decaf is a better option for afternoon pick-me-ups because coffee can stay in your system for up to ten hours, causing you to stay up until the wee hours of the morning. Switch to decaf in the afternoon to avoid a sleepless night.


Trying to figure out what’s causing your tiredness after a cup of coffee? The following commonly asked questions can help you understand why coffee makes you sleepy.

How Long Does Caffeine Stay in Your System?

It can take up to 10 hours for the effects of caffeine to wear off. Depending on how much caffeine you consume, you may begin to feel the affects as soon as 15 minutes after drinking it, although the effects usually peak approximately an hour after that. Ten hours after the first cup is consumed, half of the caffeine is still in your system, with the rest being flushed out the following day.

Can You Be Immune to Caffeine?

The term “immunity” refers to the ability to resist or avoid something. It’s possible to build up a tolerance to caffeine, but it’s impossible to build up a true “immunity” to caffeine. Caffeine, on the other hand, has been found to have a diminishing effect with time.

Can Caffeine Have the Opposite Effect?

Caffeine is commonly used as a stimulant to help people stay awake, but some people say it actually makes them sleepier. Rebound weariness, which occurs after caffeine has left your system, or other factors in your beverage, such as sugar or dairy, may be to blame.

Is Caffeine Bad For You?

Having a cup of coffee a day isn’t harmful to your health. Caffeine, on the other hand, has the potential to become addictive. Caffeine addiction can lead to symptoms including anxiety, insomnia, restlessness, and an irregular heartbeat if it’s a frequent habit.

Caffeine consumption should be closely monitored to ensure safety. For most adults, the FDA recommends no more than 400 mg of caffeine per day, which is about four 8-ounce glasses.

If you’ve been having trouble waking up after your morning cup of joe, it’s possible that something else is interfering. To make the morning transition a little easier on your body, you might want to try waking up naturally.

A restful night’s sleep is the foundation of a productive morning. If you’re looking for a good night’s sleep, have a look at our high-tech mattresses.

How long does it take for coffee to take effect?

As little as 10 minutes after ingesting caffeine, you’ll start to feel the effects, and the quantity of caffeine in your blood will peak within 30 to 90 minutes. Despite the fact that you may no longer feel the effects after a few hours, it takes a long time for caffeine to totally exit your system.

Can caffeine not affect you?

Caffeine tolerance develops over time with regular consumption, so you may no longer feel the effects of your usual cup of joe. Caffeine tolerance varies from person to person.

Is caffeine bad for your heart?

There have been numerous research on the link between caffeine, coffee, and coronary heart disease, but the conclusions vary widely. The results may have been influenced by other factors, such as a person’s nutrition. The American Heart Association recommends that people drink no more than one or two cups of coffee each day.

“Caffeine is more often associated with benefit than harm for a range of health outcomes across different measures of exposure, including high versus low, any versus none, and one extra cup a day,” according to a 2017 analysis.

How does caffeine affect your sleep?

Caffeine can keep you awake at night, so it’s best to avoid it before bedtime. Even if you consume coffee six hours before going to bed, you may still experience its effects the next day. Depending on your age, the half-life of caffeine is anywhere from three to seven hours, depending on how much caffeine you ingest.

The Latest Time You Should Drink Coffee, According to Science | by Melissa Chu | Mission.org | Medium

How do you flush out caffeine?

There are many ways to deal with a mild caffeine overdose, including drinking more water, exercising more, and eating. Relaxation can be achieved by drinking herbal tea and completing breathing exercises.

Why do I get sleepy after drinking coffee?

Caffeine has a calming effect on the body, making you sleepy after a cup of joe. Because it may be giving you stress or dehydrating you, this might contribute to tiredness. Mold may be present in low-cost coffee, which might make you tired. Sugary coffee drinks, on the other hand, can lead to a sugar slump.

Is it bad to have coffee every day?

Coffee is not likely to harm you if you drink it in moderation. If you limit your daily intake to no more than four eight-ounce cups, you should be fine. Overdosing on this amount could have a detrimental impact on your health and body.

How long does it take for coffee to affect me?

Caffeine’s effects can take as little as 10 minutes to kick in, but you’ll certainly experience the full effects within 30 to 90 minutes. If you’ve developed a tolerance to caffeine, you may be mainly unaffected by the stimulant’s effects after a few hours.

What do you think?

Rate this post