There is a lot of focus on dietary and nutritional supplements these days. Everything from pre-workouts to energy powders and drinks claim to give you mental focus and increase your workout capabilities.

Many are tempted to speed up the results by taking far more than the recommended daily serving sizes. But the real question is how much harm can this cause? Can a pre-workout kill you?

In this review, we look at all of the possible causes and factors that lead to the answer being yes.

Let us start off by saying that death from high-quality pre-workouts is very unlikely. You have to go out of your way to do any long-term harm to yourself.

However, there are some health risks because of the interactions with natural body compounds, amino acids, and blood oxygen levels.

As with any dietary aid, even if you are in peak physical health, there will be some danger. Likewise, if you know you have certain medical conditions, you should always talk to your doctor before beginning any supplementation regimen.

How Much Is Too Much Caffeine In Pre-Workout?

To stay within the recommended dosage of 400 mg or less per day, you need to closely monitor your intake levels. A single cup of coffee contains about 90 mg; your pre-workouts can have as much as 300 mg. Studies show that more than 5g can be fatal [1].

Caffeine affects everyone differently, so you must be cautious about your intake levels. Some people are hypersensitive (highly affected), and others are hyposensitive (almost no effect). Regardless of how it makes you feel, you should still limit your daily intake to 400mg or less.

This means if you are one that wakes up to a cup of coffee, has another cup on the way to work, downs an energy drink, and then take a pre-workout with high caffeine levels before your workout, you may already be over 400 mg.

At that point, you might as well ask yourself "how much caffeine do I really need" and "is my caffeine tolerance actually high or have I become dependent"?

Jokes aside, to avoid an overdose, you need to know how much you are taking at one time as well as throughout an entire day. As long as you stay below the 400 mg recommended limit, you should be fine. 

Dry Scooping Leading To Choking Or Heart Attack

One of the newer trends is to take your pre-workout without mixing it with water. A term called dry scooping, this can cause a lot of problems, and it is highly recommended that you do not follow this trend.

The biggest concern with dry scooping is that the powder mix can congeal in your mouth or throat and become lodged, blocking air passage. You can easily choke on the powder with no way to get it down or back out. You may cough and sneeze, or you could faint and eventually suffocate.

man taking supplements in the gym

Dry scooping has no advantages and only comes with potential disadvantages. It is easily avoided, and to remain safe, as well as ensure you get the full benefits of your pre-workout, always mix with proper amounts of water.

What Happens If You Take Too Much Pre-Workout?

Too much pre-workout can be a problem. If you take too much you will have some side effects of pre-workout. You can feel anxious, become jittery of pre-workout or even experience a small skin rash and tingling sensations known as a niacin flush.

All of these symptoms are temporary and will subside in a few minutes. You can also take the mix with more water to help dilute it further or take less than the serving suggestion until your body is acclimated to the ingredients.

What to Do When You Take Too Much Pre-Workout?

If you take too much pre-workout, it's essential to stay calm, hydrate, and consult a healthcare professional as soon as possible, as taking too much pre-workout can lead to jitteriness, anxiety, tachycardia, high blood pressure and other serious health risks.

As you know, most pre-workout supplements contain a blend of various ingredients, including caffeine, nitric oxide boosters (citrulline), and other ingredients designed to improve mental alertness and exercise performance. 

Taking too much of a pre-workout supplement can result in caffeine overdose, which will lead to the symptoms mentioned above. 

So, if you find that you've consumed too much pre-workout, stay calm and drink plenty of water. If symptoms persist or if you have a pre-existing medical condition that might exacerbate these effects, seek medical attention immediately. 

dry scooping pre-workout

Can Pre-Workout Cause Heart Problems?

Yes, taking pre-workout supplements can lead to heart problems, especially if you happen to suffer from cardiovascular issues, such as severe coronary disease (CAD).

As mentioned previously, high doses of caffeine can cause high blood pressure, or they can restrict your blood flow (caffeine's a vasoconstrictor) leading to stress on the heart and potentially a heart attack if your cardiovascular health isn’t solid. 

As said, many pre-workout supplements contain stimulants like caffeine that can boost exercise performance. However, stimulants can also cause high blood pressure and other cardiovascular issues in those with pre-existing medical conditions.

But even if you’re a healthy adult, consuming too much pre-workout can put undue stress on the heart, leading to serious cardiovascular problems. 

Therefore, it's crucial to understand the effects of pre-workout on your body and choose pre-workout supplements that align with your caffeine tolerance and overall health. 

Monitoring caffeine consumption, knowing how much caffeine is in your pre-workouts, and going out of your way not to consume more than 400 mg a day can minimize these risks.

Can You Overdose on Pre-Workout?

Yes, you can overdose on pre-workout, especially when taking pre-workout supplements, without adhering to the recommended dosages. 

At the same time, caffeine overdose isn’t the only thing to worry about, as there are still products available containing banned substances like DMAA or deterenol, which you can also overdose on.

That said, overdosing on pre-workout isn’t exactly a genuine concern. 

Many pre-workout supplements include high levels of caffeine, but as long as you follow the guidelines regarding the dosing - you should be fine. 

At the same time, the risk of overdosing can be further elevated with products including banned substances like DMAA, octodrine, deterenol, or even ephedrine, which can, in synergy with caffeine, overwhelm your heart and body to the point of serious consequences.

Luckily, the supplement industry doesn’t only exist to satisfy stim junkies. 

Much safer, stimulant-free products like Transparent Labs Stim-Free Pre-Workout do exist, so if you’re on top of your caffeine consumption or worried about over-stimulating your body - you can tickle two tummies with one finger.

5 Short-Term Side Effects Of Some Pre-Workouts

Even if you follow the recommended dosage amounts, pre-workout consumption over the long term can have some powerful side effects.

1. Adrenal Fatigue

Known as HPA-Dysfunction, or HPA-D, stress on the adrenal glands can lead to adrenal fatigue. This is a central nervous system dysfunction that can leave you feeling exhausted, having a cloudy mind, or experiencing rapid mood swings [2].

2. Insomnia

There is little doubt that caffeine can lead to sleepless nights and tossing and turning until you do finally fall asleep. Sleep is one of the crucial elements of a proper workout routine, including a proper diet and monitoring your calories.

With a stimulant like caffeine in such high doses within a single scoop or pre-workout, you may find yourself staying awake far longer than you want.

On average, caffeine has a half-life of about 5 hours. With high-intensity workouts, though, you can cut this down to about 2 hours. Hypersensitive people, though, may feel the stimulating effects of the drug up to 9 hours later. Taking pre-workout late in the day can affect your sleeping habits.

3. Headache

Headaches are one of the most common side effects reported with these supplements. Caffeine is a reason, but other ingredients list headache as a side effect, too.

Whey protein is known for causing headaches. So are other ingredients like arginine, L-citrulline, and even creatine.

Because these ingredients cause vasodilation, or the opening of small blood vessels, these vessels expand and contract. Blocking or sudden rushes of blood to your brain can trigger a headache or migraine.

4. Dehydration

Taking these workout supplements can cause frequent urination. If you do not drink water, you may also find yourself with gastrointestinal distress that can lead to diarrhea. Combined with the frequent trips to the bathroom, you may experience dehydration.

Replenishing bodily fluids, electrolytes, and of course, just water, will help combat these symptoms.

5. Skin Rash And Paresthesia

Beta-alanine and niacin are both known to cause vasodilation, flushing of the skin around the face, extremities and back, as well as a burning or tingling sensation. While these side effects are typically mild and only last a few minutes, they can be cause for concern in some individuals.

Known as Paresthesia, the tingling or burning sensation along with the splotchy rash can become long-term and take longer to disappear.

To avoid this, you want to use a pre-workout with low levels of beta-alanine or niacin, and remember to cycle pre-workout ingestion.

headache from taking pre-workout

4 Long-Term Side-Effects Of Pre-Workouts

Your workouts, fitness goals, and weight loss concerns may push you to reach that next level of performance. Using a pre-workout to help you obtain those goals is typically fine. However, with repeated, long-term usage, there can be some nasty, negative long-term side effects.

1. Risk Of Cardiovascular Disorders

Heart disease lives on the dark side of the pre-workout debate. The leading cause of this is due to higher doses of caffeine and other stimulants to get you motivated to perform.

Whether you exercise daily or once a week, you can take too much caffeine, and that little extra boost may lead to long-term heart conditions.

Increasing blood pressure or causing irregular heartbeats may lead to a heart attack, especially for those sensitive to caffeine or who already have coronary disease risks.

2. Risk Of Liver Damage

Most pre-workout brands will tell you what ingredients are included (as they are required by law to do so). However, they aren’t required to always tell you exactly how much of an ingredient is used. Known as proprietary blends, their manufacturing process and exact recipe are protected.

So, can pre-workout cause liver damage? If you can't monitor the amount of niacin you ingest, you can easily overdose—tolerable limits of niacin fall between 30 and 50 mg per day. Anything higher can lead to liver damage, acute hepatitis, and even diminished liver function.

To note, many brands have 15 to 25 mg of niacin per serving, which is already near the daily limit. If you double your single serving size or take in a manner not recommended, you can easily reach or surpass the tolerable daily limit.

3. Digestive Issues

Having to stop your gym session and run to the bathroom isn’t part of your plan. While it may happen from time to time, it shouldn’t happen because of your pre-workouts.

High levels of niacin, as well as creatine, L-arginine, and other additives, can cause major cramping, upset stomach, diarrhea, and make it dangerous to work out.

4. Psychological Dangers

Another often overlooked aspect is the "addiction" side of things. These supplements are on the market and advertised to help you gain performance and muscle in the gym. Once you take pre-workouts and feel the effects or have a single great gym session, you may want more [3].

Over time, you can come to rely on the pre-workouts to give you that boost, and you may not be able to perform without taking pre-workouts. In some cases, highly addictive personalities have been known to stop their workout and take another scoop, therefore can get addicted to pre-workout supplements.

Pre-workout supplements are designed to be taken once a day and only on days you go to the gym. It is also advised that you run a pre-workout supplement cycle, taking a few weeks off to let the product flush completely from your system before starting again.

Along with getting enough sleep, drinking lots of water and avoiding fatty foods (while increasing proteins and carbohydrates) will only help you feel better, perform higher, and become less dependent on dangerous substances that might kill you.

man drinking pre-workout from a shaker bottle

Common Pre-Workout Danger Questions

Are pre-workout supplements bad for your heart?

Pre-workout supplements on heart health can vary depending on individual sensitivity and the specific ingredients in the supplement. While some pre-workout supplements with high levels of stimulants like caffeine may pose risks to heart health, choosing lower-stimulant or stimulant-free options and using them in moderation can help minimize potential negative effects.

How old should you be to take pre-workout supplements?

It is recommended that only adults of legal age in their area (typically 18) take supplements for their exercise routines. Anyone can head to the local market and buy pre-workouts. This doesn't mean that anyone of any age should ingest them. Have in mind that the FDA doesn't regulate supplements, vitamins and minerals too much.

Can pre-workout cause your energy levels to crash quicker?

Pre-workouts have an effect on the body, and high stimulation comes with a crash. However, because you are hitting the gym and performing vigorous exercises, the crash isn't as strong or as noticeable. However, once the ingredients are flushed from the body or diluted enough, you can crash faster than if you weren't on them in the first place.

Why do I feel sick after taking pre-workout?

You might feel sick after taking pre-workouts due to the high caffeine content or other ingredients, such as beta-alanine, that are known to cause nausea. Therefore, understanding the effects of pre-workout ingredients on your body can help in choosing the right product.

Why do I feel nauseous after a pre-workout?

You may feel nauseous after a pre-workout powder if you’ve taken it on an empty stomach or if there’s an ingredient in there your body is sensitive to. To mitigate these effects, try lowering the dose, examining the label for any suspicious ingredients, and taking a pre-workout after you’ve eaten a meal.


As you can see, a pre-workout supplement can, in fact, kill you, but the chances of that happening are rather slim. On the same note, the main risks associated with pre-workout supplements are excessive daily caffeine intake and the practice of dry scooping.

Thankfully, both risks can be easily avoided by opting for stimulant-free pre-workout options and ensuring the proper dilution of pre-workout powder with water or a suitable liquid.

With that in mind, one of the best caffeine free options on the market that won't cause your heart to beat out of your chest is Transparent Labs Stim-Free pre-workout, so maybe give that one a try?



Miloš Lepotic

Miloš Lepotic

Meet Miloš, a certified sports nutritionist and self-taught supplement expert whose pharmacological background and nearly a decade of gym experience make him the perfect guide for optimizing your health and athletic performance through supplement reviews and practical advice rooted in factual, science-backed information.