Why Does Pre Workout Make You Itch? The Surprising Answer


Pre-workouts are energy-boosting supplements many people take before hitting the gym.

They can provide a powerful jolt, helping you lift heavy and achieve your strength and fitness goals, but they aren’t without side effects.

Pre-workout can provoke a sense of tingliness or itchiness in the skin due to acute paresthesia. This paresthesia is brought on by a key ingredient in many pre-workouts: beta-alanine. While this side effect can be irritating, it isn’t harmful.

While pre-workout can cause itchiness, this doesn’t mean it’s necessarily bad for you to take on a regular basis.

There are plenty of reasons to take pre-workout supplements, especially if you’re looking to build muscle and lift heavier than before when you go to the gym.

Unfortunately, though there are several side effects associated with pre-workouts; so it’s worth knowing what you can expect.

The Itch-inducing Ingredients


There’s only one ingredient in pre-workout that’s associated with provoking itchiness in the skin, and that’s beta-alanine.

beta-alanine, a non-essential amino acid, is a common ingredient for pre-workout supplements because it increases muscle endurance helping you sustain your output throughout an intense workout.

It’s one of the star ingredients that’s responsible for giving you an extra edge as it reduces acid production in the muscles which boosts your staying power.

However, beta-alanine also causes another effect in the body outside of the muscles. Unfortunately, the amino acid triggers certain receptors in skin neurons which brings on that familiar sense of tingling or itching you might have come to associate pre-workout supplements with.

The scientific term for skin itchiness is Paraesthesia, but since the sensation is usually short-lived in this context it’s referred to as acute paresthesia.

It only takes a dose of 1g of beta-alanine to cause this acute paresthesia, so if you’re keen to avoid this skin sensation altogether pay close attention to the pre-workout supplement’s label.


It isn’t just beta-alanine that’s a common culprit for causing itchiness, though, as there’s another ingredient in some pre-workouts that provokes a similar response in the skin: niacin.

Niacin, otherwise known as vitamin B3, has also been known to trigger unwanted sensations on the skin when taken in significant doses.

The reason why some supplement manufacturers opt for large doses of niacin is typically to cut costs, since beta-alanine is a more expensive ingredient to produce.

Should You Avoid These Ingredients?

So the fact that there are ingredients in many pre-workout supplements that cause the skin to tingle or itch begs the question as to whether you should avoid them if possible.

This is a much-debated issue, since those manufacturers that produce pre-workout supplements without the ingredients will tell you beta-alanine and Niacin aren’t necessary, while those who do use them will tell you that they are essential.

Of course, if there is a supplement that can provide the same energy kick but without the itchiness then that would be the perfect option, but are beta-alanine and Niacin key ingredients for the pre-workout energy boost?

Before we tackle the issue of effectiveness, lets take a look at whether or not it’s harmful to ingest these ingredients on a regular basis.

Are they Harmful?

If you’re worried that the skin-tingling sensation you experience when taking pre-workout is cause for concern, rest assured it shouldn’t be.

Many people report this symptom from taking pre-workout supplements and it’s a perfectly normal reaction to have with both beta-alanine and Niacin consumption.

Most people think of the itchiness caused by beta-alanine as an unfortunate side effect, nothing more.

There is no significant evidence that consuming the ingredient frequently will lead to any kind of long-term skin irritation or damage.

In fact, many people take this side effect as a sign that the supplement is actually working, and see it as a positive indicator of the pre-workout’s effectiveness.

If you derive some benefit from taking a pre-workout supplement, and you can tolerate the itchiness, re-framing it as a positive thing isn’t the worst idea.

This sensation on the skin acts as a clear indicator that the pre-workout is starting to kick in, which informs you when you should start your workout.

Are they Effective?

Beta-Alanine creates carnosine in the body which is proven to boost muscle endurance and reduce fatigue.

As such, it is absolutely an effective ingredient when used in a pre-workout supplement.

If you need to be able to sustain force over an extended period of time, beta-alanine can help you do so without burning out quite as quickly.

As for niacin, there is less evidence to suggest that it’s quite as effective in pre-workouts, but it does still provide some benefits.

Niacin can dilate the blood vessels, allowing for greater blood flow which should help you achieve a ‘pump’ during your workout and potentially give you a performance boost.

Plus, as we’ve already mentioned, while the acute paresthesia brought on by both ingredients can be irritating, it can also be seen as a sign of the pre-workouts effectiveness.

Other Side Effects

Itchiness isn’t the only commonly-reported side effect associated with taking pre-workout supplements. Here are some others you might experience:


Headaches are quite a common side effect associated with pre-workout supplements, and this is usually a direct result of dehydration.

Since some of the ingredients in pre-workouts pull water from some parts of the body to support the muscles, you can be at risk of dehydration if you aren’t careful to drink enough water.

This dehydration can thin out the fluid around the brain which can cause headaches as a result.

Another cause of headaches is the dilation of blood vessels which is caused by several pre-workout ingredients.


Some ingredients in pre-workout supplements can have a laxative effect which can of course cause unwanted bowel movements.

Caffeine is one such ingredient that is often used in high doses, but there are several others that can contribute to the laxative effect.

This issue is a lot worse for those with sensitive stomachs, so it pays to be aware of your body.


Due to strong stimulants such as caffeine in pre-workout supplements, the last thing you want to do is take one too close to your bedtime.

If you want to get a late-night workout in, try to do so without taking a pre-workout supplement, since otherwise you might have a hard time getting to sleep.

Frequently Asked Questions About Pre Workout Itchiness

How long does pre-workout itch last?

The itch brought on by niacin or beta-alanine in pre-workout will typically be felt around 15 minutes after consuming the supplement.

When the acute paresthesia kicks in, you can expect it to last for around half an hour.

This can depend on the person, though, as well as the dose of either ingredient present in the pre-workout.

How do you stop itching from pre-workout?

The best way to stop itching from a pre-workout is to stagger your doses, so you aren’t getting it all in one go.

If you mix up your approach and take small doses throughout the day rather than one big one before going to the gym, this can prevent the itching.

This is because the itching is a result of a significant dose of either ingredient, so if you reduce the dose, you should reduce the itching.

Is Beta-Alanine bad for you?

No, beta-alanine is an amino acid that is found in many foods and dietary supplements.

It can have positive effects on muscle endurance and performance, and it is used commonly before workouts.

When consumed in significant doses, as part of a pre-workout for example, it can cause itchiness but this shouldn’t be cause for concern.

A Final Word From Energetic Lifestyle

While pre-workouts can cause itchiness if they include beta-alanine or large amounts of niacin, the sensation is just that, and isn’t harmful.

If you want to avoid the sensation altogether, you can split up your dose.

Alternatively, you can choose to see it as a positive, in that the sensation lets you know when the pre-workout kicks in allowing you to time your workouts effectively.

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Article by:

Energetic Lifestyle Team

Our detailed review has been contributed to by multiple members of the Energetic Lifestyle Review Team to ensure the best research and highest standard of quality. Have a good or a bad experience with one of the products? Please let us know, we love the feedback!

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