Energy Drink Side Effects

Energy drinks can have potential side effects if not consumed responsibly or as directed.

Energy Drinks

Because of the vast array of ingredients in Energy Drinks, it may make them more likely to produce side effects than beverages containing just caffeine alone.

What’s worse, the safety of energy drinks has become a major issue as consumption has increased among children and teens.1

Top 10 Energy Drink Side Effects

Recent research in Australia2 has highlighted the risks with over-consumption of energy drinks. This data was gathered from 7 years of calls to the Australian Poisons Center.

Listed in order of most common to least common:

  1. Palpitations / tachycardia
  2. Tremor / shaking
  3. Agitation / restlessness
  4. Gastrointestinal upset
  5. Chest pain/ischemia
  6. Dizziness/syncope
  7. Paresthesia (tingling or numbing of the skin)
  8. Insomnia
  9. Respiratory distress
  10. Headache

The Center for Food Safety Adverse Event Reporting System (CAERS) received over 140 complaints about adverse side effects from 5 Hour Energy, Monster, and Rockstar over the last 10 years. Some of these resulted in hospitalization and death. See the report here.

If you’ve experienced other energy drink side effects tell us about them in the comments below.

Energy drinks contain supplements, herbs, and vitamins and are required to list warnings on the label about consuming more than the recommended serving.


Potential Problems from the Specific Ingredients

In moderation most people will have no adverse, short-term side effects from drinking an energy drink, however, the long-term side effects of consuming energy drinks aren’t fully understood as of yet.

wean caffeine

However, if you have reached a state of dependence on energy drinks, then it’s time to start considering products specifically designed for helping you kick caffeine without withdrawal. Of those out there, we endorse Wean Caffeine which is highly effective and inexpensive.

Let’s take a look at the most common energy drink ingredients and list the potential side effects that could result from ingesting too much.


This is the most common energy drink ingredient and one of the most widely consumed substances in the world.

Caffeine tolerance varies between individuals, but for most people, a dose of over 400mg/day may produce some initial symptoms: restlessness, increased heartbeat, and insomnia.

Higher dosages can lead to:

  • Increased blood pressure
  • Heart palpitations
  • Anxiety and panic attacks
  • Gastrointestinal disturbance (diarrhea)
  • Increased urination
  • Dizziness, irritability, nausea, nervousness, jitters
  • Allergic reactions can include; rash, hives, itching, difficulty breathing, tightness in the chest, swelling of the (mouth, face, lips, or tongue), diarrhea, shakiness, trouble sleeping, vomiting
  • Headaches and severe fatigue from withdrawal
  • Painful withdrawal symptoms

(Read more about caffeine overdose here)

Caffeine can be found in other natural ingredients such as guarana,  green tea extract, and coffee extract or can go by many other names, so be aware of this when reading energy drink labels.

Please consult the caffeine database for an exhaustive list of caffeine in energy drinks (and other drinks). This is updated weekly.

Adrenal Fatigue

There is debate as to whether adrenal fatigue is a real disorder, but here’s what some think happens.

Some people can become tired even after consumption of caffeine. This is believed to be a symptom of adrenal fatigue where the body’s aadrenalinesystem has become overtaxed by the constant high caffeine intake.

The solution is not to increase caffeine even more – but to reduce, detox, and get the adrenal glands back to a healthy state.

Remember, it’s hard to pinpoint an exact safe dose because it varies from person to person and according to a person’s tolerance.

See our Caffeine Safe Dose Guide here.

Between 500 milligrams to 1000 milligrams in a 24 hour period will probably lead to some of the more severe side effects.

Click here to find out how much caffeine in different energy drinks would be deadly.


Most energy drinks are high in sugar in the form of high fructose corn syrup and/or cane sugar. Some use creative names to make their version of sugar seem “healthier”, like “natural cane juice”.

  • High sugar drinks are linked to the obesity.
  • Sugar causes tooth decay
  • Increases risk of type 2 diabetes.
  • The sugar in energy drinks causes blood sugar and insulin spikes, which later result in a “crash-like” feeling.
  • Sugar is also somewhat addictive.


No side effects from the Taurine3 in energy drinks have been documented.  Some countries (France, Denmark, and Norway) originally banned energy drinks because of their taurine content, but have since accepted that taurine consumption is safe based on the evidence to date.

The amount placed in energy drinks is well below what would be needed for therapeutic benefits or for any potential side-effects.

B Vitamins

  • More than 35mg of Niacin (B3) can cause flushing of the skin. Intake of 3000mg or more can result in liver toxicity. The British Journal of Medicine recently published a case study of a man who consumed about 5 energy drinks a day for a period of three weeks. This caused toxic levels of niacin to build up in his body, leading to nonviral hepatitis.  The unidentified energy drink in question supplied 200% of the RDA of B3. A summary is found here.
  • More than 100mg of B6 can cause sensory nerve problems (burning sensation) or skin lesions.


No major side effects have been reported, but it could cause dizziness, tiredness, headaches and an upset stomach. (src.) Ingesting large quantities has been linked to diarrhea. Large doses have been used to treat certain psychiatric disorders.


  • Some studies have linked it to sleeplessness, while others refute this.
  • Other possible symptoms include; low blood pressure, edema, palpitations, tachycardia, cerebral arteritis, vertigo, headache, insomnia, mania, vaginal bleeding, amenorrhea, fever, appetite suppression, pruritus, cholestatic hepatitis, mastalgia, euphoria, and miscarriage.


While no side effects have been reported, there’s still debate on its safety.4  Many countries including Canada, England, Germany, and France have concluded that it is not a safety concern.

Artificial Sweeteners

If you drink sugar-free energy drinks you may be consuming any number of artificial sweeteners. There is always debate around the negative health effects of these (particularly aspartame5).

However, all major health institutions regard them as safe.

Ginkgo Biloba

Gingko is a herb, and can cause some minor side effects in some people6:

  • nausea, diarrhea, headaches, dizziness, heart palpitations, and restlessness.
  • Can interact with other medication such as blood thinners and anti-depressants.
  • A recent study found that ginkgo caused thyroid cancer in rats.


Too much of this amino acid can cause vomiting, nausea, headache, diarrhea, stuffy nose, restlessness and sleeping difficulty.7


This amino acid is derived from green tea and many energy drinks and shots have begun putting “green tea extract” in their products.

It produces a different type of alertness than caffeine and there hasn’t been any scientific evidence of it causing adverse side effects. Some have reported feeling light-headed when consuming a dose of more than 300mg of L-Theanine.8

What is Safe For You?

Energy drinks probably shouldn’t be a staple of anyone’s diet and coffee is certainly a healthier source of caffeine.

However, despite a number of alarming reports of overdose in recent years, for most people energy drink consumption is fine in moderation.

Many reported side effects are anecdotal – being reported from patient’s records. So, it’s hard to say which ingredient actually caused the problems if the patient was ingesting several combinations of these at one time.

Be Careful of Pre-existing Conditions

If you or your child has a pre-existing heart condition of any sort – they should not be consuming energy drinks.

In general, it is better to avoid the larger drinks (i.e. Mega Monster has a massive 240mg caffeine in its 24 fl oz giant can) and stick to smaller 8oz cans.

If people drink energy products responsibly and use energy drinks occasionally, then most will likely avoid any of the energy drink side effects.

Get Help Quitting Caffeine

Reduce your caffeine intake without pain and discomfort.

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  • ted

    The author is and the date is 2012

  • Cassidy

    Haha yea i chugged a monster before i ran the mile..those things are sooo good:) and the next day i was itching all over like crazy and i was swelling up:'( now i cant drink no more monster

  • T-Bow

    This is helping me to help my friend to do a project so be quiet Jo Bob

  • Volante

    This information is very, very helpful. My brother uses energy supplements way too much and I’m hoping that websites like this will help him. Thank you!

  • energy are good never tell people different.

  • Headache Boy

    I suffer from a condition called cluster headaches and I consume about six 250ml cans per day. It is belived that the combo of caffeine and taurine , caffeine being a vascular con strictor and taurine being a calsium tract antagonist,helps to reduce the level of pain we experiance or even abort a low level attack.Wilst I have had hart palpatations and jitters in the past from over consumption , so far I’ve not experianced any other side effects yet….
    I find the use of energy drinks for this condition to be preferable to other meds available some of which have much worse side effects.

    Grate caution should be used if you are useing hart meds like verapamill(a calcium trak antagonist) as the taurine can have a cumlative effect causeing serious hart problems.

    Sorry about my spelling , I just thought I should put this out there.

  • vaesavali

    THnaks for sharing this…I love drinking water but all of a sudden seen my friends drinking red bull for energy including my son who is serving in the Marine..I think its good to know about this so would aware of quiting drinking those energy drinks!
    this is a good idea for my daughters science fair project!

  • Victoria

    Well done! Am currently working on energy drinks consumption and it side effects. Pls i would need more informations on the subject with citations and references.

  • Will

    I have a cousin that drinks Monster, she drinks it everyday when shes alone, away from her parents I told her to not drink them and now she has a pimple problem and now I use it against her to not drink energy drinks. But that that falled and now when I see a person with an energy drink I say in a Russian Voice “Energy Drinks are for P****s

  • Worried Mom

    Today is Thursday. My sixteen year-old son drank one of these monster drinks on Sunday. Starting on Monday he has been unbearable. I have begged him to act as though he cared about someone besides himself. You can tell by watching him he isn’t in control of himself. Today is Thursday and no improvement. I am almost ready to through him out of my life. I pray to Jesus that my patients holds out longer than the effects of the Monster drink. If you believe in God please pray for me. Please pray he will never touch another Monster drink again. This isn’t the first time we have had major problems with this. Monster drinks make my loving son a MONSTER. He is not himself when he drinks them. Only by the grace of God he nor I have been killed by each other. Please tell people stay away from these energy drinks.
    I read where one person with cluster headaches it helped. Go to the herb shop and buy some taurine.

  • uoijuhboiuo

    dude i drink a lot of energy drinks.i have seen for a month that without doing anything i get you think this is a side effect of the energy drinks?and if yes how am i able to get it out of my system?

  • ted

    @worried mom, The energy drink’s effects wouldn’t last that long.. I think your son is taking something else….

  • Stupid son

    This Friday I was so stupid to heaving try a rockstar will I was skiing and I could not for the life of me not to tell my parents so I did and my mom told me to look this websit so I did and I saw the side effects of the drink and I am truly grate full that I am still alive today I will never touch a another energy drink again or else I could not live with myself

  • Sup Crazy ppl

    Well now this is quite an interesting read,however i dare any of you to point out anything that isn’t unhealthy when overconsumed.
    PS. Worried Mom i can kind of see why your son on drugs, insted of blogging about it get him some help!

  • feathers

    GRRRRRRR sorry I am hooked on rockstar doing 2 a day give me another one!!! Love the stuff feel so alive when I drink a can of it!!

  • Lee

    WOrried mom I just sent one up for your son now praying he will be ok. I am diabetic have high blood pressure and high cholestrol depression etc alot of health problems. I can drink one can and feel soo good I drink the sugarfree. I did notice today I had 2 of them and I started to sweat very bad. I quit drinking 24 years ago but I feel I can’t give up this energy drink it has me hooked. 🙁 Please people if your thinking about trying it don’t do it!! Please don’t do it!! God Bless All of you and best of luck in your futures!! 🙂

  • Lee

    please if you never tryed energy drinks dont do it you will be hooked I think about it 24 hours a day!!!!!

  • Karen Berquist

    I started drinking energy drinks just last year, and I am seriously addicted. I don’t go through withdrawls but that taste of a blue Amp and the energy I get, I just miss it. It’s very hard to quit, but when I go a day or two without it, I hate it but It also helps my health even more.


    Ok, are you people all 12? You are on a caffeine website!!! Caffeine is a DRUG, every one knows that. So are the thousands of prescriptions that our doctors write out every day that when you get filled, you get a 4 page leaflet that include POSSIBLE SIDE EFFECTS. COMMON SENSE FOLKS! Body mass, allergies, ilnesses are all factors. Not to mention, for all you naturalists out there, even the wonderful supplements available to us (ie: someone commented to get a taurine supplement) are manufacturedsome people can AND WILL have issues. And uneducated newbies that mean well have wrecked their liver and kidneys listening to the high school kid behind the counter at their local vitamin world or health food store. Also, some people need to learn the term IN MODERATION, Monster contains diuretics, duh if that is the only thing that you drink, not good, but if it works for YOU PERSONALLY, and you are not overboard, you will be fine!

  • Joe

    I get tired when I drink energy drinks the reason is if you have add or adhd stims work dif on you. I take adderall that is amphetamine if you don’t know. Its for my add and a lot stronger then caffeine by far. Heck Meth slows me to a crawl .

Last Modified: November 10, 2017