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

Reduce your caffeine intake without pain and discomfort.

See our new 10-step plan
  • Arnie

    I’ve had 7 coffees, 8 cans of pantha and 2 rockstars today and I am angry at everthing and everyone. I need some diazepam to sleep or I’ll be up all night. Please email some to me. :-}

  • Ashley

    I kinda find these story really hard to believe..I mean, I’ve consumed 7 energy drinks in 4 days before and I’m still living, and I’m 16 years old. I’d say I’m a caffeine addict. I have caffeine pills that are 200mg each and I pop about 3 a day washed down with coke zero, coffee and tea. I had one week where I was on a energy drink frenzy but I’m flat out broke because they cost so much..the pills are $6 for 100. One tip, don’t let your health freak teacher find out your addiction, otherwise you’ll have to do a presentation on caffeine in front of the class like me. That’s why I’m on this site.

  • Josh

    I agree with Ashley, the most caffeine I have consumed in 1 day was 2 23oz Monsters and 1 Amp Focus (16oz) can. I got the jitters after that, but that is pretty much it. I have a collection of energy drink cans in my room (aprox. 50 cans). I have been collecting these since September of 2011, so far I seem fine. Either these stories are just almost impossible to believe, or I have a extremely high caffeine tolerance. In my life I am guessing I have had over 75 energy drinks in 2 years. I am 16 years old.

  • Jorge

    I used to drink energy drinks like they were water. One day, I found an old, off-brand energy drink in my fridge that had been in there for months, already opened. I decided to drink it (stupid). After difficulty breathing and heart palpitations, I ended up in the hospital. They diagnosed caffeine overdose.

    Months later, after staying away from energy drinks, I tried a Decaf 5 Hour Energy…Started to experience a lot of the effects I had felt when I had overdosed. Luckily I hadn’t had enough to make me go back to the ER, but I realized that it was the B-vitamins in the drink that I was sensitive to (as it was a Decaf drink).

    I guess my point is, sometimes caffeine overdose is misdiagnosed, too. I really don’t think there are many caffeine-caused deaths.

  • Mary H

    Im with Jorge, I have had the same problems. You can OD on caffeine. LEAVE THE ENERGY DRINKS ALONE

  • PhilBeeNZ

    Many of these comments sound like teenagers claiming high consumption to prove how tough they are.
    Before you guys think excessive caffeine consumption won’t hurt you, you might like to check out this link – a 30yr.old woman here in NZ drank 7.5L of Coca-Cola and smoked 30 cigarettes a day, and died of cardiac arrest.
    So, STILL wanna be macho?

    [ ]

  • michael

    im 12 and i consume about 1200 milligrams of caffeine a week so…

  • garrick

    I had to go to hospital lastnight after having a redbull and 10 ‘regmaker’ pills(150mg caffeine each) the evening before while drinking..was the worst experience I have had..but don’t usualy have lots of it,so body was probably not that used too it..won’t be that stupid again!

  • Haley

    I love caffeine as long as it is way before bed (afternoonish) but currently I am drinking like 8 cans of caffeinated diet pepsi to stay awake and do a stupid research essay, (procrastination =_=”) I don’t feel nausea or any of the symptoms does that mean it would be sufficiently fine for me to go through the rest of today (seeing as it is three in the morning)drinking more pepsis to stay alert for classes?

  • sam

    im 22 and have a slight addiction! i drink on average 5 cans a day, alot less than i used to but cant function until i have a can, i have been drinkin them everyday from when i waqs 16, it started because i had glandular fever which sapped my energy levels!

  • Ben

    I’m 17 and I’m doing a Certificate 2 in Hospitality.
    Today I did Prepare and serve espresso coffee in which I drunk 7 short black(4 where from other people who didn’t drink theres), 1 Long Macchiato, 3 Cappuccino, 2-3 Flat white(not sure how many exactly) and 2 Mochachinos.
    Towards the end of todays course I started to get Overdose Symptoms like Jitters, Increased heartbeat, Nausea, Anxiety, Sweating and Dizziness. The person running the course noticed me acting weird, at the end of the class he ask me why, so I told him how much I have drank and he took me home strait away instead of me walking home (I wish he took me to the hospital) because I’ve been sitting here shaking for last 5+ hours and it’s only just starting go away and I’m so glade it is.
    I will never have more then 1 cup of coffee again (1 cup is the most I’ve had in one day).

  • ted

    @michael-1200mg a week is less than 200mg a day so I think you’re not in any danger of overdosing….

  • truth

    Its true what there saying it happened to me. After a while it will catch on its not a sudden reaction of too much caffeine

  • Cierra

    I like energy drinks and all of that ill have one about every 3 weeks or so. The last time i had one was 2 weeks ago at school during luch time i was soo jittery i couldnt sit still for 5 mins and i was studering and shaking badly.I like them but im not stupid like some people who drink 7 a day. i’d be off the walls and im only 13

  • somebody

    Dunno why but one addiction I had When I was like 8 or something one day i had a few Cappuccinos and I felt so addicted. I had a Boost energy drink when I was like 11 or something and I hated the taste .. Only recently (I’m 14 now) I’ve started drinking energy drinks more often now and kind of like the taste n seem to be addicted but I’m kind of tolerant.. One week I could have a like maybe 5 of the cheap 35p energy drinks and a few Boosts and the next few I’d deal without them .. Never tried a rockstar or monster but I’m gonna soon my friend was sat next to me drinking an apple monster and I was like ahhh I’ve got to have one!!

  • Bob

    My question to the caffeine Overdose is whether it’s cumulative or a one time shot (like dogs eating chocolate).
    I have felt the effects of too much caffeine, one time actually scared me (and my coworkers), but on any given day I’ll have an energy drink (>1/2 gram).
    If you’re drinking/taking the caffeine to stay awake, you honestly shouldn’t feel any different. You just don’t have a need to sleep right away. If you feel the ‘buzz’, that is your body saying you’ve had enough, taking ore won’t help your cause.
    And the average result of too much caffeine is throwing up, or wishing you would.
    Most teenagers use it because of the hype we adults have put on it, that morning cup of coffee you ‘have’ to have to get you’re day started.
    This is just my point of view, but one I’ve experienced and I hope it helps someone. Btw.. if you stop completely, you will most likely have a piercing headache for a couple of days.. then it goes away. I have had that every time 🙂

  • Aaron

    I drink at least 5 espresso doubles a day at work = to at least 1000mg of caff. plus 4 cups of coffee and one energy drink everyday and I sleep great every night

  • ted

    Overdose is from a toxic amount of caffeine in the system at one time. The caffeine molecule breaks down pretty quickly but this can vary among people.

  • Tim

    I’m 8 and I eat coffee with a spoon, washed down with 6 monsters a day. These stories are fake.

  • Desi

    Ummm Tim, these stories aren’t fake, I think the only thing fake is your comment. I highly doubt your parents would let you do that. Now run along and go play with action figures.

    In my opinion this article really helped me with my research report, thank you so much!

Last Modified: November 13, 2017


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