Why Do Some Pre Workouts Make You Feel Sick or Nauseous?


Whether or not you’ve had a bad experience with pre workout supplements before, you’ve definitely read complains about them causing people to feel sick or nauseous.

In fact, this is one of the things that originally put us off trying pre workouts – back when we knew little about nutrients when we were younger.

So why do people take pre workout supplements?

Answer – The best products deliver benefits to improve your gym session:

  • Train longer, for harder – Increased endurance allows you to make more progress every gym session.
  • Stay focused on your goals – Make the most of every rep and keep your phone in your pocket!
  • Lift bigger weights – You’ll be stronger than before, increasing your bench press & squat.
  • Feel your arms and legs pump up – Intense muscle pumps make you feel amazing, and even promote muscle growth.

Once you started learning about supplement ingredients, you realize that the products that cause side effects contain ingredients that are likely to cause them (in this case nausea or sickness.

In this article, you’ll find out:

  • Pre Workout Ingredients To Avoid
  • Best Pre Workout Ingredients
  • How To Choose The Best Product
  • Conclusion

Pre Workout Ingredients To Avoid

Simply put, the reason why some experience sickness or nausea after taking a pre workout, is because they chose the wrong product. There are many pre workouts on the market, that contain potentially harmful ingredients – or ingredients that have been over-dosed.

We’ll take you through which ingredient you should stay away from, to avoid any unwanted side effects in this section.

Take a look:


Also known as Bitter Orange Peel, this ingredient is more commonly seen in fat burners – due to it’s ability to promote fat loss.

However, companies still include Synephrine in pre workouts as it can also be used as a stimulant (which would improve alertness and focus in the gym.

But don’t be blinded by this ingredient’s benefits – it’s potentially very harmful.

In fact, Synephrine is a main cause of nausea and sickness in pre workouts; so this is at the top of our list of nutrients to avoid.

Side Effects:

  • Nausea
  • Sickness
  • High Blood Pressure


First of all, it’s important to know that DMAA’s been banned in the USA – ingredients don’t just get banned for no reason, so this should be enough to keep you away.

This ingredient can also cause both nausea and sickness, as well as a range of other unwanted side effects; so we definitely recommend avoiding any pre workouts that contain DMAA.

Side Effects: 

  • Nausea
  • Sickness
  • Rapid Heartbeat
  • High Blood Pressure

HIGH DOSAGES of Caffeine

Read this very carefully. You should avoid pre workouts containing caffeine when it’s been dosed over 200-300mg per serving. 

Anyone who’s had too many coffee’s in a short time frame will know it’s side effects – nausea, sickness, and rapid heartbeat.

However, you have to remember that this stimulant is consumed daily, around the world.

Q: Why do companies add high dosages of caffeine in pre workouts?

A: Because they want their pre workout to ‘pack the most punch’. Basically, caffeine can affect you almost instantly (within 30 minutes), so by adding high amounts of caffeine, companies want to fool you into thinking their pre workout is really working.

But the problem is, you’ll experience a big boost – but then suffer from side effects not long afterwards.

How to avoid problems with Caffeine

When dosed correctly (between 150-200mg per serving), caffeine is a key pre workout ingredient – in fact, it’s the most beneficial ingredient at providing you with energy boosts, which makes it almost essential to a pre workout.

To avoid experiencing unnecessary side effects with caffeine, make sure to avoid any pre workout supplements that contain over 200-300mg per serving.

Here’s some tips:

  • If you’re sensitive to caffeine – Stay under 200mg per serving, and you’ll experience caffeine’s benefits, without feeling sick or nauseous.
  • If you’re tolerant to caffeine – If you consume caffeine alot, then you’ll probably be able to handle up to 300mg per serving without experiencing side effects. But still avoid pre workouts that contain over this dosage (many products exceed 300mg).

To See The Best Ingredients, Read Our
Pre Workout Ingredients That Work Article


Read More About The Benefits of Pre Workout Supplements

How To Choose The Best Product

Now you know which ingredients to avoid, you can see which are the best by clicking the link above. Ultimately, a pre workout’s ingredient determines whether it will be safe and effective.

For this reason, we’ve searched the market for the best product (that contains the best ingredients, and doesn’t contain any potentially harmful ones).

Here’s our top pre workout, as of 2018: 

4 Gauge by Roar Ambition

After testing and being disappointed by countless pre workout supplements, we’re glad we found 4 Gauge.

It was one of the few products that gave us energy boosts, without the dreaded jitters or energy crash after – we believe this is because it has an optimal dosage of caffeine inside (150mg per serving).

Most importantly, 4 Gauge improved our workouts and didn’t make us feel sick or nauseous – so it gets the thumbs up from us.

Here’s the main benefits we experienced:

  • Intense Muscle Pumps – we experienced skin-splitting muscle pumps when bicep curling or leg pressing.
  • Strength Boost – We squeezed out those extra few reps at the end of our set.
  • Enhanced Cognitive Function – we were able to concentrate more on our workout, wasting less time and making more progress in the gym.
  • More Energy – The correct dosage of caffeine really helped to give us a boost, helping when we were too tired and unmotivated to train.
  • No Side Effects or Energy Crashes – We believe this is because 4 Gauge only contains 100% natural ingredients, without any artificial sweeteners.

Learn Why It’s So Effective:

This pre-workout is the full-package – it gave us all the benefits we needed to improve our workout, and get the best results. You can learn how it helped me push harder in the gym below:

– Read my 4 Gauge Review –

Or visit their website www.4Gauge.com


In Conclusion, the answer to the question “Why do some pre workouts make you feel sick or nauseous” is this: because you chose a bad product that contained ingredients responsible for these side effects.

Ultimately, to avoid side effects, you need to check the ingredients in the product you’re consuming – to make sure there aren’t any potentially harmful ingredients, or any large dosages that can cause side effects.

But don’t be put off Caffeine.

As we’ve mentioned, Caffeine is one of the most beneficial ingredients in a pre workout – most people look for that boost to smash their workout, and this is exactly what caffeine delivers (as well as increased strength and endurance).

Just remember to check the dosage of caffeine, and only take pre workouts that contain 150-200mg per serving – to avoid jitters, energy crashes, feeling sick and nauseous.

2 thoughts on “Why Do Some Pre Workouts Make You Feel Sick or Nauseous?”

  1. Hello,
    Before I start, I just want to say that this article was very helpful. So I just bought a preworkout and took some, and felt nauseous. Upon looking at the ingredients, I just noticed that it has 300mg of caffeine per serving. Could I potentially still have the same effects if I take half a serving as my preworkout? Thank you in advance!

    Rating: 5
    • Hi Frank,

      Glad you liked the article. What supplement are you talking about? If you mean 4 Gauge, this has 150mg of Caffeine per serving. We – and most users we’ve spoken to – find this is the perfect amount to help them focus without the jitters.


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