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
  • Anon

    Well, I’m 16 and I’ve been drinking coffee since I was alive and energy drinks since I was 12. If I don’t have a good dose of caffeine a day I start to live my life as though nothing had happened. It may be the life time devotion or it may be genetics but I’ve never felt the symptoms of caffeine withdrawal even when I quit caffeine entirely for about half a year. I consume caffeine again but, not on the regular anymore. Energy drinks are nothing more than another tasty beverage to me.

  • Karen


    Just would like to say that I am pregnant,so I don’t drink coffee anymore…
    For those who are looking a good substitute for coffee, I can recommend a date coffee called dattero, it’s made from dates.

  • Colten

    I was able to take about 1.5-2.0 grams of caffeine in one night (about 4 hours time) it was 4 pills and 20 or so mountain dews. I did not feel any of the symptoms of overdose. It helped me stay alert and awake for the night I had. I ate a good amount of apples and steak that night so it wasn’t on an empty stomach.
    I feel I may have built up a tolerance to caffeine because I was able to do this, even though on a normal day I will have around 100mg of caffeine (4-5 mountain dews).
    My friend who is about twice my size took around 1 gram and he started vomiting and he felt terrible the entire day. (it was over about the same amount of time)

    I believe this shows it is based on the individual, and not just size.

  • pam

    lm 2 months pregnant i just want to know if lucozade is safe to drink

  • ted

    @Pam, Lucozade has caffeine in it and I think most doctors recommend to limit caffeine consumption while being pregnant. 🙂

  • dan

    I hover around 3-5 Redline X-treme bottles a day at work. No jitters, no headaches.

    Then again i have to down a bottle of burbon when i get home just to fall asleep. sooo, that coupled with chain smoking… god… I’m in trouble =P

  • Dale ‘HubbaJnr’ Chinskie

    Yo!? Im A 15 Year Old Boy From Inverness, Scotland, Uk. Im In Care And My Dad Died Two Weeks Ago. Today 22,December,2011, I Looked Up To My Dad Very Much. Since He Died I Had Enough, Weeks Later (Well Today) I Had 3 monster energy shots 2 Bottles Of Lucozade Energy And 2 Cans Of Monster energy. I Felt Very Very Weak About 1 Hour Later And Could Hardly Move. Felt Soo Dizzy And Everything Was Like Really Slow. I Dont Think Ill Do This Agen Im Puting A Word Out To ALL People if its not too late Do not try something like this. DHJC!

  • Crystos

    This site is awesome. Thank you guys for creating it and maintaining it…

  • Mark

    I’ve worked in coffee shops, espresso has become like water to me. energy drinks, became soda. I no longer feel the burn out the next day with out coffee or energy drinks, and only once when I was younger did I have heart palpation from overdosing energy drinks but since then my body has built up a wonderful tolerance so I get to enjoy the drinks. I know they aren’t for everyone but I do love my espresso and energy drinks.

  • Anon

    In 2009 when I was 18 I was a heavy user of caffeine. I have sleeping problems (not sleeping alot) and caffeine was what helped give me a boost so my body would not crash after nights of not sleeping.

    However, it got to the stage where I was using caffeine in the same way as an illegal drug, taking more and more because I was not getting the same buzz.

    I tried No Doz, caffiene drinks, supplements, chewing gum, etc.

    I was consuming more and more until the night I took a deathly amount of No Doz (approx 29 – 32 no doz plus (have glucose)) tablets from failing to count how many I had already taken during the day (I would mix with food and drink; including energy drinks and, take by themselves).

    I am still alive and my organs are still working.

    However, on the day I took them I experienced all of the above… Usual symptoms as well as blacking out and in terms of vomit it was bloody. The only symptom I did not experience to my knowledge is cardiac arrest however, it is possible this happened.

    I know I was pretty close to dying.

    I now stay away from caffeine and if I do use it, it is in the occasional Blue V or Red Demon I buy down at the petrol station.

    If I have any more than this I experience headaches and 6 to 8 of the symptoms above.

    My story is true and idiotic.

    On a funny side though I once read about some guy in the USA who got pulled up for driving erratically because he had drunken 20 cans of red bull (unsure of mls). Report said he thought everything was moving slower than him (kinda like speed). The report also stated he was lucky to be alive.

  • What a bunch of babies

    Today i’ve had 5 rockstars, 7 caffeine pills 200mg and a cup of coffee. Im not dead but I don’t recommend it I just really like how caffeine makes me feel

  • Courtney

    Like recently for the past 2 years, I have been drinking Rockstars, Mountain Dew, Coke, and Dr. Pepper a lot. And just recently, like the past 3 days, I have been feeling very dizzy, headaches, very tired even though I get like 8-10 hours of sleep a night. Hard time concentrating. And I’ve had to like go home from school because I’m feeling so crappy. I’m wondering and thinking that is it most likely caffeine thats doing this to me? I can’t really think of anything else.

  • philip

    lol im a major addict i drink them when i feel down or depressed and gets me back to happy I JUST DONT RECCOMEND STARTING THEM CUZ ITS VERY HARD to get off and never try drinking 10 energy drinks or so plus on top of like 4 sodas B.A.D but anyway cool site

  • Jess.

    boy have I learnt, tonight I overdosed and it was the worst ever…
    I honestly thought I was going to die… 🙁
    water is my only drink I shall drink for now.
    I learnt the hardway! 🙁

  • Melanie

    My boyfriend is addicted to rockstar. I pray for his health and safety every night before we go to bed.

  • curtis

    I have about 2-3g of caffeine daily. I drink about 2-3 pots of coffee (measured 12 cups per pot). It simply increases concentration a TON for me. Though I do normally crash about 8-9 hours later depending on how fast I consumed it, and what else I consumed with it.

  • ted

    Wow Curtis, that’s an insane amount. You need a detox to reset your caffeine tolerance 🙂

  • Dot

    I think caffeine intake has caught up with me. After years of drinking very strong coffee, my heartbeat is rapid, I’m nervous, on edge, and I’m hoping that I can cut it down considerably. I can barely handle 2 sips without feeling very nervous, and my heartbeat is at 85. It used to be in the 60s. No fun.

  • Worried Mother

    My daughter is 12 and she has had 18 rockstars in her life as she told me. Should I call the doctor?

  • ted

    In her whole life or in one day? In one day yes, in her whole life no.

Last Modified: November 13, 2017


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