Caffeine Overdose Symptoms: Signs, Cases, Prevention


Top 10 Caffeine Overdose Symptoms

Here are the usual symptoms in order from the first ones to be experienced to the more severe, later stage consequences.

  1. Jitters, Restlessness, and Nervousness
  2. Increased heartbeat
  3. Nausea
  4. Anxiety
  5. Heart palpitations (cardiac arrhythmia)
  6. Insomnia
  7. Sweating
  8. Dizziness
  9. Vomiting
  10. Cardiac arrest

There can be many common symptoms that indicate too much caffeine consumption, but these are the most prevalent.

These symptoms should be recognized and further caffeine intake should be stopped to avoid more serious and even life-threatening symptoms.

Ingesting massive doses of caffeine all at once is particularly dangerous as it doesn’t give your body time to react. Overdose symptoms serve as an early warning system.

Caffeine’s major effects are experienced for at least 4 hours.

  • This is longer for those sensitive to caffeine.
  • This is longer with extremely large doses.
  • This is based on the half-life of caffeine which is 4-6 hours.

It’s hard to pinpoint an amount of caffeine that will cause these caffeine overdose symptoms as people have different tolerance levels.

Are You Addicted to Caffeine?

You may want to consider quitting. A detox program like Wean Caffeine is scientifically designed to help you quit caffeine gradually and safely. This prevents the horrible withdrawal most people experience when quitting.

Prevention: Maximum Daily Intake

You can prevent caffeine overdose by adhering to the recommended safe dosage guidelines.

Generally, a dose between 250-500mg (check caffeine amounts here) could produce some of the above mild to moderate symptoms, especially in those with no tolerance of high caffeine sensitivity.

Those with a caffeine allergy or sensitivity could have severe symptoms even after a very small dose.

Click here to find out how much of a popular drink would it take for you to overdose.

DSM-5 Criteria

Insomnia is a common symptom of too much caffeine

Caffeine Intoxication is now included in the DSM-5 physicians manual.

The official diagnosis can be made when any 5 of the following symptoms are present: restlessness, nervousness, excitement, insomnia, flushed face, diuresis (you keep passing urine), gastrointestinal disturbance (upset tummy, diarrhea), muscle twitching, rambling flow of thought and speech, tachycardia or cardiac arrhythmia, periods of inexhaustibility, or psychomotor agitation.

The DSM-5 now also lists Caffeine Withdrawal as a mental disorder. Sufferers can experience withdrawal symptoms when ceasing caffeine intake.

Caffeine Addiction as a disorder was rejected from the next version of the manual.

Reducing the Impact of Caffeine

There is some research indicating products that contain rutaecarpine can actually reduce the impact of caffeine’s side effects. They do this by assisting with caffeine metabolism*. Learn more here.

Caffeine Overdose Documented Cases

Caffeine overdose does happen and has been documented. Here are some of the more recent cases resulting in death or hospitalization;

  • 19-year-old James Stone dies after taking 25 to 30 No Doz pills in 2007. (at least 2.5 grams of caffeine)
  • 40 Seagulls die from caffeine overdose in Canada this year from eating used coffee grinds.
  • 17-year-old Jasmine Willis, a Durham, UK waitress overdosed by drinking 7 double espressos in 2007. She was taken to the hospital but recovered soon after. (that’s roughly 1.078 grams)
  • In the late 1990’s an Australian woman, with a heart condition died after consuming a guarana based shot from her local health food store. This product is no longer on the market. (10g/liter, ok that’s just nuts!)
  • 2010 a 23-year-old British man from Mansfield, England died after taking to 2 spoonfuls of pure caffeine powder washed down by an energy drink at a party. His death was ruled accidental.
  • 2011 Fourteen-year-old Anais Fournier, died after she consumed two 24 ounce Monsters (480mg of caffeine) in a 24 hour period. The cause of death was a heart arrhythmia due to caffeine toxicity.  There seem to be some conflicting stories as to how much she really consumed and this seems true since 480mg in a 24 hour period isn’t a toxic amount. Update October 2012: Her parents are suing Monster Energy for wrongful death although the girl did have a known pre-existing heart condition.
  • 2012 The FDA is investigating Monster Energy since the energy drink has been linked to five deaths over the past year.
  • 2013: According to the Substance Abuse and Mental Health Services Administration, energy drink-related ER visits have doubled in the last 4 years, however, 42% of these visits involved caffeine in combination with other drugs such as alcohol or other narcotics. src.
  • 2013 a New Zealand woman died from cardiac arrhythmia associated with her 10 liter/day Coca-Cola habit. She also smoked 30 cigarettes a day and barely ate. Caffeine was a contributing factor, but the 900-1000mg daily dose wasn’t the only factor. src.
  • 2013 A mother is suing Monster Energy for the death of her 19-year-old son, Alex Morris, after he died of cardiac arrest. She claims that he drank two 16 ounce Monsters the day before his death and at least two a day for the 3 years preceding his death. A California Coroner’s office reported that he died from cardiomyopathy and cardiac arrhythmia.
  • October 2013: John Jackson from the UK dies after eating a whole tin of HERO Energy Mints. Each tin contains 12 mints, so he consumed 984mg of caffeine. He also had cirrhosis of the liver, which prevented him from processing the caffeine properly allowing it to build up in his bloodstream to lethal levels. (src.)
  • March 2014: A 14-year-old boy from Norway was hospitalized with kidney failure after drinking 4 liters of a caffeine-laced energy drink while gaming for 16 hours straight. This would be around 1,280mg of caffeine if he was consuming a “Red Bull” like energy drink. (src.)
  • September 2014: A Tennessee man was taken to the hospital after consuming 20 caffeine pills to “test the limits of his body” according to what the man told the paramedics. He ingested 4000 mg of caffeine at once. src.

Caffeine Overdose Facts

too-much-caffeineLuckily for us, we have mechanisms built into the human body that let us know we’ve had enough of something.

This is true with caffeine overdose. Well before we are at a toxic level we experience side effects that prevent us from consuming more, i.e. nausea and vomiting.

This means that before the 149 or so cans of Red Bull that it would take to kill an average adult male, vomiting would most certainly happen.

For most, that would happen after about can number 5!

It’s important to note, however, that caffeine is a drug and should be respected and not abused. Since some people have extremely low tolerance to caffeine, they could  – in theory – overdose quite easily.

How to Know If You’ve Overdosed

Most people feel the “jitters” first – a sensation of tremors or shaking.

This is your signal to stop consuming caffeine for the day.

You should also be aware of the caffeine levels in what you are drinking. Please consult the caffeine database. Some of the caffeine amounts will surprise you.

If you are finding you are often tired after consuming caffeine this is a sign that you need to change your long-term habits and could indicate adrenal fatigue.

The bottom line is to be aware of what you are consuming.

How common is caffeine overdose?

With the plethora of caffeinated products in the marketplace, one could assume that overdosing on caffeine is quite common.

If we look at the statistics from The American Association of Poison Control Centers we find that, while it does exist, it isn’t as common as we might think.

In fact, overdosing on Tylenol is a lot more common than overdosing on caffeine.

Since caffeine is consumed so widely, there are a lot of half-truths, hearsay, urban legends, media hype, and even fiction.

It’s good to take an honest look at the subject and try to put all of the information into perspective. We can then determine if caffeine should be in the same category as other drug overdoses are.

Get Help Quitting Caffeine

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  • wow. I’m probly gonna die soon…I’m not even 16 yet!

  • Josh

    Thank you so much for having common sense. At least someone else knows that education is the best prevention!

    Also I love this site!

  • Dusty

    Here’s a fun website too:

    9 teenagers die an alcohol-related death per DAY. We probably don’t even known of 9 caffeine-related teenage deaths TOTAL

  • dess

    I drink an energy drink a day some times 2

  • Nick Jaekel

    Unless you’re allergic to caffeine, or chugging 2 Redline, the chances of you dying from that is pretty much 0%. Most energy drinks don’t have much over 180 mg., so 2 is nearly harmless. Most packages only warn you after 3. The most I’ve had in like an 8 hour period is 2 cocaines and 2 monsters, that’s 880 mg. but I only had one at a time with probably 1 and a half to 2 hours between. I was fine, I was laughing hysterically while playing Still Alive on Rock Band though.

  • Yeah, I useally drink 1 to 2 drinks a day always looking for the next “high”. My usual course consists of about 3 8oz Red Bulls, a Rockstar 24oz and a Monster 16oz. Sometimes I’ll throw in a can of Cocaine instead of the bulls. Been doing this for years and the Redlines aren’t too bad. Somedays I drink a whole one in one sitting then I’m falling asleep an hour or two later feeling like a trainwreck 🙂 According to GNC the most “daily” recommended amount of caffeine a day is 700mg. Everyday for a month and then take a little break but then you crash 🙁

  • DiGiTaLoVeR

    I drink so much Pepsi…I Love it!

  • Mike Stone

    Products like “Blow” and “Energy Shots” are seriously dangerous. I’m currently writing a report on “energy drinks” for university, and some of the information I have found is really quite disturbing. Did you know that “energy drinks” are only sold in drug stores in Norway? And France and Denmark have banned the drinks altogether? Keep in mind, this information is sourced from academic journals, and not from Wikipedia (like this site).

    In 2006 as many as 500 new energy drinks were introduced worldwide, and this number is growing rapidly. The energy drink industry is extremely lucrative, and competing companies are blatantly ignoring the serious health issues relating to energy drinks, just so they can get a slice of the profits.

    I don’t mind the odd Red Bull now and again, but when products which have seriously high levels of caffeine, and are so concentrated, are available to “teens”, some serious action needs to be taken by the government. It’s only a matter of time until a child manages to get hold of some “energy shots” and dies. And please don’t give me the pathetic argument that “the child should know better” or “it’s their own fault”. The blame should, and will, rest solely on the producers.

    Some of the arguments posted on this site, such as “lighten up” and “don’t take these sorts of things so seriously” are void of any cognitive process whatsoever. I actually feel sorry for some of you people, because you’re so bild to the real issues in the world.

    I personally hope that the government acts swiftly and passes legistation to finally bring these products into line.

  • ted

    Mike why don’t you gather all the documented evidence and research that shows they are so dangerous and then why not compare that to the impact alcohol has on society, health, and kids….Not even in the same ball park my friend. However there is no out cry from any of those countries to ban alcohol is there? How many kids have overdosed on alcohol and died? so as far as real issues are concerned, I agree, energy drinks just doesn’t happen to be one. Why not put your energies into ending poverty, abuse, drug addiction, family violence, disease, smoking etc. They are the real issues not some kids having a bit too much caffeine.

  • Mike Stone

    Thanks for your reply Ted; however, I disagree with your logic. I believe this issue has a greater knock-on effect than most people realize. As to your statement regarding alcohol and its affects on teens and health, you only have to look in most bottle shops to see the increasing number of alcoholic energy drinks available, with their attractive packaging and links to extreme sports; it’s becoming hard to distinguish between alcoholic and non-alcoholic drinks. Children are being groomed from young ages by large corporations to consume these drinks. Don’t you think this is fueling alcoholism in society (especially teen binge drinking)?

    Another point for you to ponder. Since the introduction of “Red Bull and Vodka” in almost every bar around the world, people are drinking themselves into a state of “wide-awake inebriation”, where he or she believes they can operate a vehicle, or do other activities that require absolute concentration, because they are wide awake. Is this not a serious issue? Red Bull claim not to endorse the mixing of alcohol with their product, however, their action speak differently, e.g. promotions in bars.

    Alcohol has been around since 9000BC, so there’s plenty of evidence regarding its effects. However, energy drinks have only been around for about 20 years, and the demand has only recently increased in the last few years. Ergo, the documented evidence is limited but still strong. Does this mean we should discount it?

    I agree that there are issues in the world which are obviously more serious than this, but I believe it’s an issue that should be addressed before it spirals out of control. How far will these producers and marketers push the envelope? Also, if you didn’t already know, caffeine is a drug, and people suffer withdrawal symptoms after consuming excessive quantities.

    I plan to put my time and energy into greater causes (human rights) once I finish my law degree Ted; but I have to study for the time being, and this issue is my focus at the moment. Also, poverty and smoking will never end; don’t be so naive.

    I await your reply.



  • Dusty

    Mike, thanks for all your insightful input. Rarely do we get commentary that’s as well thought out and produced as yours. From my point of view, though, your decision to toss around mentions of law school and “greater causes” do not lend your points one bit of credence. Not one, so knock it off it’s embarrassing.

    Why did I attack that angle of undermining the integrity of your stance? Because one of your greatest thesis points here seems to be our lack proper information sourcing. You’re accusing us of leaning on transparent terminology like “lighten up” as our primary weaponry. Of making claims from shady information sources. My first request, then, is that you yourself back your self up. You’re making the claims after all making that your duty, AND you’re writing a paper. Those still require proper sourcing, no?

    The most important point I want to make, though, is that you’re placing energy drinks and caffeine into the same category. This is odd, because educated opponents of energy drinks realize that caffeine is also found in coffee, and to make a direct stance against energy drinks they must attack the energy drink ingredients that coffee does not have.

    This is always fun, because at that point all arguments fall apart. Why? There is NOT ONE body of scientific evidence indicating that energy drinks are more harmful than coffee. Caffeine is the source of the blame game here, and coffee has it in higher concentrations than nearly every energy drink out there.

    So why aren’t you attacking Star Bucks? Because their packaging doesn’t come in satanic colors that dupe children into killing themselves? That’s a joke. At least energy drink companies make efforts to put warning labels on their containers. It’s my stance that energy drink vendors are responsible for not heading the risks of the products they sell. You say it’s always the producer who’s responsible for their products problems once in the hands of a free consumer? That’s a downright silly statement. Seriously, ask yourself where our economy would be today if we always blamed product manufacturers for the improper use of their products. Car makers would be out of business, dog breeders would be put in jail, it’d be a beautiful world.

    Your point about alcoholic energy drinks grooming children into alcoholism is not even worth my time. You’re reaching way too far.

    Seriously, the biggest task I ask of you is to give me scientific evidence of how energy drinks are more harmful than coffee. You do that and I will step down. All I ask of is hard correlation data, really of any kind. If you keep going on about everything else and tainting it with “greater cause” crap then I’m done. Just go join Green Peace if that’s all you’re here to argue.

    I await your reply.



  • Subway

    …and that’s why I friggin love Dusty. =)

  • David Southerland

    Here is what I believe to be a good
    lifestyle and a normal environment in
    which an adult(probably over 30) can
    keep energy drinks and enjoy them in
    a reasonable manner.

    A place or a home where there is a moderate
    level of health standards, heat and air
    conditioning, a relatively safe haven for a neighborhood to live in.

    Diet should consist of 2 or 3 meals a day
    (not junk food), a variety of liquids like
    water and juice. Supplements is a plus.

    Drinking a mixture of energy drinks and
    light spirits such as vodka sounds like
    something a very stable person with
    military history might do. I don’t know
    why but it sounds like risk-taking on
    one or more levels, one social.

    Energy drinks are a great media football,
    and on the internet at least it sounds
    like a new game for the in-health crowd.
    Using common sense is the highest precept,
    but being as the drinks are new means
    going somewhere for straight answers.

  • Dusty

    Thanks David, all very well put!

  • Dru

    I wrote this a couple years ago in response to a flailing dramatic “OMG U guise, dun drink energy drinks!!!! They’ll keeel uuuuuu! My friend drank 1 and she totally amost died!!!!” type post on a forum I post on. This is my opinion of death by energy drinks.

    Ok so I avoided for the last few days as the flame war that seemed to be getting ready to happen was just stressing me out. So I come back and the thread as been locked, so I’m going to post this here.

    If it was my friend who ODed on caffeine I’d call him/her a moron. Because that’s what they would be. Ok I’m trying to stay calm here but, like I ranted in a previous post, there are thousands of brands of energy drinks, each with different levels of caffeine, taurine, guarana, and other things.

    If it was my friend after calling her an idiot I’d ask how much caffeine was in the drink(s), how much caffeine she normally has a day, if she drank it on a empty stomach, and other question to try to drill it into her head that energy drinks are not evil, but if you’re stupid with them you can get sick.

    For instance. Are you a one cup of coffee in the morning person, or do you drink a whole pot? Do you drink it weak, normal, strong, or so strong you could remove paint with it? Do you drink soda? Are you a Coca-Cola person?( 34.5mg per 12oz can) or a Pepsi One person? (55mg per 12oz can)

    Try adding up how much caffeine you have over the course of a normal day. Now how much caffeine is in that energy drink? If it’s more then you drink over a whole day then YES it’s a pretty good bet you will get sick if you drink it. If you normally over the course of a whole day have like 200mg of caffeine then buy and drink within a short amount of time(ie anything other then the course of a whole day) something like Rockstar Zero Carb which has 240mg of caffeine per 16 ounces, then you’re going to get very sick.

    If you drink coffee, soda, energy drinks, anything with a lot of caffeine in it on a empty stomach you’re going to get sick. End of story. Even someone who has 1000mg of caffeine a day with no ill affects will get sick if they have it on a empty stomach.

    My point over this whole thing is moderation! If you want to play with caffeine to make your heart fast, great. But do it intelligently. Start with small doses and add a little more more till you get the affect you want. Don’t do for multiple drinks unless you have a lot of experience with it and know how it will affect you. And if you do get sick, don’t go whining that energy drink are evil just because you can’t control your self and/or happen to be one of those people who can’t handle energy drinks.

  • Rachel

    those of you who drink at least two energy drinks a day, should monitor yourselves closely. we do not need to lose the youth of our society due to reckless behavior. please, be careful.

  • Vega

    I made the mistake today of drinking an 18 0z energy drink and took about 3 caffeine pills. God knows what the hell I was thinking. But I’m avoiding caffeine from now. Thanks to my little bout of stupidity, I am currently mildly dehydrated as well as earlier I experienced an anxiety attack. For those of you wondering why I was dumb enough to do this. I have a phobia about sleeping and missing work. I had no sleep last night and I had to work a rather long shift. I didn’t think twice about the high amounts. From now on I limit my caffeine to one soda a day and I will always keep a bottle of water by my side. Take my word for it, Dehydration is one of the most uncomfortable sensations a person can experience.

  • Rhona

    Yesterday night i overdosed on caffeine for the first time, and i must say it was a terrifying experience. I’d had 480mg of caffeine that day (six Redbulls) and i found it insanely ironic that i – someone who does not drink or do illegal drugs – was the one to overdose, when the friends i had been with were all superbly drunk on alcohol.

  • Iron Mike

    Here’s my story from expirience. I’m a college student working as a paper boy to pay for school. I am 6’2 about 220lbs. I regularly use caffeine before school and before I workout but usually never in the same day. I’m not a doctor or in med-school. I overdosed yesterday. (for the third time in about a year) I use caffeine powder in capsule form or in a powder drink like cool-aid. I took some before school at about 6:30 and taken some before I went to the gym at noon. (I had forgotten about my morning dose and took a little extra for energy) The power is like 400mg per 1/4 tsp. my morning dose i’d estimate at about 300mg but I was hurrying to make my preworkout so I ended up putting about 1 whole scoop (I use 1/2 tsp)I took it and immediately felt it was too much. (side note- I hadn’t eaten or drank much the whole day). I did some bench press and lat pull downs and started cramping up so I went home. My stomach was a little upset but food calmed it some what. I then expirienced my normal overdose symptoms- I became really jittery and had some terrible anxiety attacks. It felt like my blood was on fire! I became very depressed and then crazy horny and back to depressed, like I was bipolar. After the psychological effects wore off I became sick. My body tried getting it out anyway it could, I’ll spare the details but was ugly.
    that phase ended but I still feel sick. This discomfort usually lasts a few day.

    The moral of the story is… I took over a gram in 6 hours. I think a cup of coffee is 50 or 100mg of caffeine. So about 10-20 cups? I didn’t die, though sometomes I wish I had. Though there are factors thAT

  • Betty

    I’ve had caffeine overdoses- and caffeine may not seem like a big deal, but take enough and it’s the worst feeling in the world. For some people, it means cold sweats, anxiety, and convulsions. For me, it means weak shakiness, rapid, pounding heartbeat, an odd kind of pressure all over- and constant, uncontrollable vomiting that won’t quit; my gag reflex won’t stop even when there’s nothing left to throw up. Literally, an unending barrage of heaving. Not fun. And one has to wait for it to wear off. This won’t occur after a few cups of coffee, but watch out for caffeine pills- also diet supplements with caffeine (or any type of stimulant, “xanthine” is basically the same)and watch out for mixing uppers like caffeine with downers like alcohol.

Last Modified: November 13, 2017


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