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
  • andrew

    Haha that seagull one was funny peta members these days lol

  • Dylan

    I drank 8 oz. of pure caffeine (5150 Juice), which is equivalent to 4000 mg of caffeine, which equals out to 4 grams of caffeine. I just went to the hospital for a day and a half, or so. I also weigh around 125.

  • ted

    Why would you do that?

  • LTBA7

    I consumed 1.848 grams today, and the symptoms are in order, thankfully it stopped right before the last one. please take this seriously, because it makes you want to kill yourself.

  • LTBA7

    Oh and “Tim”, how about you drink 12 exspressos like me and tell me how Damn great you feel, well since your supposedly 8 you would probably die, but who cares it you say the article is fake. Get your head out of your you know what if you know what’s good for you, prick…

  • paula

    hi ya i must drink at least 15 plus cups of coffee a day every day

  • Anarch

    I was taking 3 pills, 3-4 times a day that had 65mg of caffeine in them for about 10 years and this last year I had to stop because I started having anxiety attacks. No, real anxiety attacks where you feel like your heart’s either going to jump out of your chest or like it isn’t there at all…or else I was having trouble breathing and feeling like I was having a lung collapse. I’m still not completely sold on the idea that it’s “anxiety” as in a mental issue. Not that I’m sane or anything, it’s just that those attacks feel much more physical as opposed to mental.

    And before that I was a cokehead. Not that kind of coke, coca-cola. But I quit drinking it right before I started taking the Excedrin. I probably started taking the Excedrin to combat the headaches from the caffeine withdrawal…though at the time I wasn’t really concerned with excessive caffeine intake, my teeth just couldn’t take all that sugar and caramel and whatever other crap they put in their products.

    I’m down to one pill per dose, so 65mg…and soon I should be able to quit all together. Then I’ll probably die of a heart attack, anyway.

  • koydie

    hahaha all signs me probz gunna die

  • me

    I consumed 1.54 grams in the last 15 hours. I weigh 282, should be okay, right? lol

  • SS

    Thanx 4 da information, i’m taking too much of coca cola & now by just drinking one glass of coca cola, my body bcums painful “THATS A WARNING” now i think i must STOP.

  • David Crandall

    You forgot to mention urinary problems. It causes a person to wake up many times during the night to urinate. It also causes a person to not be able urinate in a timely manner even though he has a full bladder.

  • Yerbs

    After two energy drinks I start to feel a little bit funny, so I will usually stop. Then I’ll drink water to offset the effects of the drinks.

  • Dave

    I took 15 x 20mg (3 grams) caffeine tablets as a pre workout boost three days ago. I felt absolutley awful, I started getting blurred vision and vomitting, I couldnt eat I just kept trying to drink water to stop dehydration but I just brought the water back up. I was bed bound for a day and a half, my feet turned blue from bad circulation, my fingers would spasm. On the second day I stopped vomitting, but felt extremely weak. I started to replace the fluids I lost and today I have been eating quite normally again. I will never mess with caffeine supplementation again.

  • Hitomi

    I’m a paramedic and our dispatcher’s best friend called our station said that her husband went for a run and he used to down about 5 energy drinks before he went out on his morning runs but he hadn’t come home yet and she was worried about him. So my dispatcher asked us to go past her friend’s house to see if he was back from his run yet as a favor to her… No such luck so she told us which way he usually ran and we drove on his jogging route and half way through his route, there he was laying face down in the street…. dead as a doornail we worked him as a favor to our dispatcher but he was gone. Too many energy drinks all that caffeine. But he used to boast to his wife that it gave him an edge on his running performance. I don’t touch the things myself I stick to green tea…

  • Pittaz

    I Stupidly had about 10-15 maybe more, cups of coffee with in 3-4hours (give or take a bit) Worst experience of my life…I experienced all of those symptoms!
    Its stupid though! I know i’m not sensitive to caffeine because i had 5 500ml Energy drinks last New Years eve (spaced out over the night) and i did not experience any of those symptoms (Excepts cant sleep and the non-sick/scary ones).

    Never doing that again haha

  • Kitty

    We use to have caffeine parties in high school. We crush caffeine pills up and put them with the coffee and then brew several pots. We would also crush caffeine pills and lace joints with it. We’d also drink Jolt and Surge (energy drinks weren’t really popular or around when I is in HS) on top of the coffee laced with extra caffeine. It’s amazing any of us survived our teen years.

  • david

    if you consume caffeine regularly you will build up a tolerance, just like most other drugs. so the toxicity point will depend on your size and how much you normal consume. I am a 200lbs male and drink 3-4 cups(shots) worth of coffee per day, a guy half my size might be getting the jitters by that point if they did not drink coffee at all.

  • simon

    I am a 45 yr old male whose 11 year caffeine addiction has been graded as “chronic”.
    3 litres of monster green per day, plus 24 panadol extra a day and anything up to 20 cups of tea per day as well.
    Cold turkey may be my only hope as with a history of sinus tachicardia – this is a time bomb waiting to go off…..

  • JJ

    There are some really angry people on here (esp. Yue – seriously? You get mad that the writer laughs about seagulls dying so you tell him to commit suicide? Psycho…)

    Anyhow, I’m pretty sure irritability is a result of too much caffeine, so some of you might want to cut back. Just saying.


  • NeoShadows

    Damn is this article true. Seriously people, caffeine overdose is no laughing matter. Although the seagulls parts did make me chuckle. Just saying.

    Take it from someone who would of made the list of dying from Monster overdose. Cut back. When you’re not lying in bed having trouble breathing and freaking out because your heart is beating too fast to be normal, you’ll thank me.

Last Modified: November 13, 2017


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