The Side Effects of Mixing Alcohol and Caffeine

Step into any cool bar or café, and you're bound to notice an intriguing trend: the rise of caffeinated alcoholic drinks. From espresso martinis to boozy energy drink concoctions, there seems to be a growing fascination with mixing the invigorating rush of caffeine with the laid-back vibe of alcohol. It's a blend of two worlds, seemingly combining the “best” of both — or is it?

But wait! Before you mix that espresso shot with liquor, let's get the facts straight about the side effects of mixing caffeine and alcohol. What happens when you combine coffee drinks with alcohol or energy drinks and alcohol? And what about drinking coffee after drinking alcohol? Let’s find out!

What Are the Effects of Mixing Alcohol and Caffeine?

Caffeine acts as a stimulant, giving us an energy kick by blocking adenosine — a neurotransmitter that makes us feel drowsy. By inhibiting adenosine, caffeine boosts our alertness and wakefulness.

Alcohol, on the other hand, does the opposite, at least at the physiological level. Instead of ramping things up, it slows the brain's functions by increasing its production of GABA (a neurotransmitter that has calming effects) and decreasing the production of glutamate, which would typically boost brain activity. While we might feel an initial rush of energy due to the effects of feel-good neurotransmitters such as dopamine (which is also triggered by caffeine), after a few drinks we might start feeling more relaxed or even a bit sleepy. It's as if alcohol is dimming the lights to create a more mellow or drowsy vibe.

While the “coffee with liquor” combination might seem like the perfect balance to keep the night going, in reality, it's sending mixed signals to the brain and confusing the body. The caffeine is pumping up the jam, while alcohol tries to mellow things out. The result? We may feel more awake and less drunk than we really are, but our cognitive functions and decision-making skills are still very much impacted. We don’t feel as affected as we actually are, which can have some serious consequences.

At a scientific level, this combo could spell trouble. Let’s explore the 10 main side effects of mixing the two.

1. Risk of Overconsumption

Due to the muted sedative effects, there's a higher likelihood of consuming more alcohol, potentially leading to alcohol poisoning or other dangerous outcomes.

A study among Michigan high school students cited by the CDC showed that mixing alcohol with energy drinks contributed to binge drinking: those who did so were four times more likely to consume six or more drinks per occasion.

2. Mood Swings and Anxiety

Stimulants’ and depressants’ opposing effects on neurotransmitter levels can lead to mood fluctuations. The boost in dopamine from stimulants may be countered by the relaxation and potential depressant mood effects of alcohol.

While caffeine can lead to feelings of anxiety or jitters, mixing it with alcohol can exacerbate these feelings due to the unpredictability of how the two interact in the body.

The risk is especially high for teenagers and young adults. According to the CDC, in 2017, 10.6% of high-schoolers and 31.8% of people in the 19 to 28 age group reported mixing booze with energy drinks in the course of the previous year.

3. Strain on the Heart

Ever felt your heart race after a coffee or an energy drink? Caffeine’s cardiovascular side effects are well-known. Add alcohol to the mix and you could experience heart palpitations. It's a bit like asking your heart to run a marathon without proper training.

As we already know, caffeine can lead to a temporary increase in heart rate by blocking adenosine, a neurotransmitter that helps relax the heart. Without this relaxation signal, the heart pumps more quickly.

Caffeine can also cause a brief rise in blood pressure, even in people without hypertension. This effect is believed to be caused by an increase in adrenaline or by a temporary block on hormones that naturally widen our arteries.

Alcohol’s physical impacts are quite different:

• Blood vessel dilation. Alcohol has a vasodilatory effect: it expands and relaxes the blood vessels, leading to an initial decrease in blood pressure. However, chronic use might increase the risk of hypertension.
• Arrhythmias. Excessive alcohol use, especially within a short time (binge drinking), can lead to irregular heartbeats, known as arrhythmias. This irregular rhythm might feel like a fluttering heart or a heartbeat that's too fast or slow.

Put caffeine and alcohol together — especially energy drinks with alcohol or coffee drinks with alcohol directly mixed in — and your heart is receiving a dangerous mix of signals. This tug-of-war can be stressful for the heart, leading to palpitations.

The alertness from caffeine can mislead us into thinking we can consume more alcohol, leading to higher amounts of alcohol in the system, adding to its cardiotoxic effects.

4. Double Dehydration

Both alcohol and caffeine are diuretics: they encourage the body to lose fluid. Combine coffee with alcohol, and you could be setting yourself up for some serious dehydration — think parched throat, dizziness, and a headache.

Caffeine increases urine production. This diuretic effect can cause the body to lose more fluid than we’re taking in, especially if you're not counterbalancing with water.

That glass of wine or bottle of beer, in turn, comes with its own set of dehydrating traits. Alcohol inhibits an antidiuretic hormone called vasopressin, which helps the kidneys reabsorb water and concentrate urine. Without it, the kidneys send water straight to the bladder, leading to more frequent bathroom visits.

When caffeine and alcohol team up, their combined diuretic effects can be more pronounced:

• Exacerbated fluid loss. Drinking caffeinated alcoholic beverages can amplify the fluid loss from both substances — for every caffeinated alcoholic drink we have, we’re potentially losing more fluid than we would by consuming either substance alone.
• Electrolyte imbalance. Research shows that alcohol and caffeine can alter our body’s levels of essential electrolytes (such as sodium and potassium). An imbalance can lead to symptoms such as muscle cramps, dizziness, and fatigue.
• Compromised cognitive abilities. Dehydration can impair concentration and cognitive functions. When merged with alcohol's detrimental effects on cognition, this combination can lead to poor decision making and slower reaction times.

Action steps. To help you stay hydrated, consider these tips:

• The 2-for-1 rule. For every alcoholic and/or caffeinated beverage you consume, drink two glasses of water. This not only paces your intake but also helps combat the dehydrating effects of both substances.
• Hydration on demand. Always have a bottle of water on hand. Spice it up with slices of cucumber, lemon, or fresh mint for a refreshing twist.

5. Sleep Trouble

Alcohol might make us feel drowsy, but it can interfere with our REM sleep. Caffeine? Well, it's known to keep us awake — that’s why we drink it! Consuming them together can do a number on our sleep patterns. Imagine trying to sleep with a playlist that switches between lullabies and rock anthems — not exactly restful! Drinking coffee after drinking alcohol in the evenings can really mess up our sleep.

While caffeine can be our morning buddy and afternoon ally, come nighttime, it becomes a sleep saboteur. Even if we manage to drift off, research shows that caffeine can interfere with the deeper stages of sleep, leading to less restorative slumber and more of the lighter, easily disrupted phases.

As for alcohol, it often tricks people into thinking it'll help them sleep. But while alcohol can make us feel drowsy and might help us nod off faster, it doesn't promote natural sleep. Instead, it induces a sedative effect, not the refreshing sleep we desire. It’s known to reduce rapid eye movement (REM) sleep — a crucial phase of our sleep cycle, packed with dreams and deep rest. Moreover, as the effects of alcohol wear off, it can cause “rebound wakefulness” — we find ourselves waking up frequently during the second half of the night.

Mix caffeine and alcohol, and the sleep situation becomes even messier:

• Contrasting effects. While caffeine is shouting "Stay awake!" to the brain, alcohol is murmuring "Drift off ... but not too deeply." This conflict can result in a restless night, in which we’re neither fully awake nor deeply asleep.
• Extended metabolism time. Alcohol can prolong the time caffeine stays in our system. This means that even if we had caffeine earlier in the day, drinking alcohol later might increase the chances that caffeine could interfere with our sleep.
• Sleep deprivation aftermath. Poor sleep quality and reduced sleep duration can lead to a sleep deficit, magnifying the effects of alcohol and caffeine the next day. As a result, we find ourselves in a vicious cycle as we consume more of one or both to compensate.

Action steps. To keep alcohol and caffeine from wreaking havoc on your sleep, try this:

1. Tech timeout. Alcohol and caffeine can already interfere with sleep, so give your body an extra hand. An hour before bed, switch off your tech — smartphones, laptops, and TVs. The blue light from screens can interfere with production of melatonin, a hormone essential for sleep.
2. Stretch before sleep. Engage in a 10-minute gentle stretch or yoga routine before bed to relax muscles and joints that might have been tensed due to caffeine. This practice can also act as a physical signal your body that it's time to wind down.
3. Soundscapes. Play calming background sounds, like ocean waves or forest ambiance, as you drift off. This masks noisy outside disturbances and keeps the mind distracted from the alertness caused by caffeine or restlessness from alcohol.

Set Yourself Up for Success

Finally, here are some general steps to consider adding to your routine to set up a solid foundation for better sleep and overall health. Every step, no matter how small, is a leap towards a rejuvenated you!

• Be your own barista. Explore gourmet decaf coffees and herbal teas. With so many flavors and blends, who needs the added buzz of alcohol or jolt of caffeine? There’s so much to explore beyond the coffee-alcohol world.
• Mocktail madness. Experiment with alcohol-free mocktails. Ever tried a raspberry rose fizz or a citrus mint cooler? Delicious, refreshing, and no sneaky side effects!
• Mind the clock. Set a “caffeine curfew.” Decide on a specific time (e.g., 2 PM) after which you won’t consume any caffeine. This will give your body ample time to metabolize the caffeine and prepare for rest. Before bedtime, opt for herbal teas such as chamomile, valerian root, or lavender. They’re naturally caffeine-free and have properties that can promote relaxation and sleep.
• Awareness is key. Keep a journal. Note how you feel after drinking various beverages. You might find that certain drinks leave you feeling better than others.
• Get moving. Swap the cocktail glass for dancing shoes or take a walk. Physical activity is a great way to boost your mood and energy naturally.
• Seek support. Share your goals with friends and family. Surrounding yourself with a supportive squad can make your journey to cut back on alcohol more enjoyable and sustainable.

Wrapping Up

While mixing caffeine and alcohol might seem like the go-to for a vibrant night out, it's not quite the winning combination we might want. Moreover, there’s a world of relaxing and stimulating experiences out there waiting to be explored. Thinking about grabbing a caffeinated beer or mixing some alcohol and energy drinks? Take a step back and consider your health and well-being.

The next time you're reaching for a drink, think twice about that alcohol-caffeine combo. Why not try a late-night cooking class or an early-morning yoga session? Go ahead and attend that local music event you've been eyeing, or dive into a captivating book that's been on your reading list forever.

We all have different ways to recharge and celebrate. The idea is to make choices that not only feel good in the moment but also leave us feeling great the next day. Embracing healthier habits or trying new activities can be just as thrilling — if not more so — than either caffeine and booze. As we venture forth, let's remember that genuine, fulfilling experiences can come when we least expect them and often happen outside our usual routines. Dive in, enjoy, and prioritize your well-being. Cheers to healthier choices and joyful moments ahead!