What happens if you overdose?

From Desk Reference to the Diagnostic Criteria from DSM-3-R (American Psychiatric Association, 1987):

Caffeine-Induced Organic Mental Disorder 305.90 Caffeine Intoxication

  1. Recent consumption of caffeine, usually in excess of 250 mg.
  2. At least five of the following signs:
    1. restlessness
    2. nervousness
    3. excitement
    4. insomnia
    5. flushed face
    6. diuresis
    7. gastrointestinal disturbance
    8. muscle twitching
    9. rambling flow of thought and speech
    10. tachycardia or cardiac arrhythmia
    11. periods of inexhaustibility
    12. psychomotor agitation
  3. Not due to any physical or other mental disorder, such as an Anxiety Disorder.

Basically, overdosing on caffeine will probably be very very unpleasant but not kill or deliver permanent damage. However, People do die from it.

Toxic dose

The LD_50 of caffeine (that is the lethal dosage reported to kill 50% of the population) is estimated at 10 grams for oral administration. As it is usually the case, lethal dosage varies from individual to individual according to weight. Ingestion of 150mg/kg of caffeine seems to be the LD_50 for all people. That is, people weighting 50 kilos have an LD_50 of approx. 7.5 grams, people weighting 80 kilos have an LD_50 of about 12 grams.

In cups of coffee the LD_50 varies from 50 to 200 cups of coffee or about 50 vivarins (200mg each).

One exceptional case documents survival after ingesting 24 grams. The minimum lethal dose ever reported was 3.2 grams intravenously, this does not represent the oral MLD (minimum lethal dose).

In small children ingestion of 35 mg/kg can lead to moderate toxicity. The amount of caffeine in an average cup of coffee is 50 - 200 mg. Infants metabolize caffeine very slowly.


  • Acute caffeine poisoning gives early symptoms of anorexia, tremor, and restlessness. Followed by nausea, vomiting, tachycardia, and confusion. Serious intoxication may cause delirium, seizures, supraventricular and ventricular tachyarrhythmias, hypokalemia, and hyperglycemia.
  • Chronic high-dose caffeine intake can lead to nervousness, irritability, anxiety, tremulousness, muscle twitching, insomnia, palpitations and hyperreflexia. For blood testing, cross-reaction with theophylline assays will detect toxic amounts. (Method IA) Blood concentration of 1-10 mg/L is normal in coffee drinkers, while 80 mg/L has been associated with death.
  • Emergency Measures
    • Maintain the airway and assist ventilation. (See Appendix A)
    • Treat seizures & hypotension if they occur.
    • Hypokalemia usually goes away by itself.
    • Monitor Vital Signs.
  • Specific drugs & antidotes. Beta blockers effectively reverse cardiotoxic effects mediated by excessive beta-adrenergic stimulation. Treat hypotension or tachyarrhythmias with intravenous propanolol, .01 - .02 mg/kg. , or esmolol, .05 mg/kg , carefully titrated with low doses. Esmolol is preferred because of its short half life and low cardioselectivity.
  • Decontamination
    • Induce vomiting or perform gastric lavage.
    • Administer activated charcoal and cathartic.
    • Gut emptying is probably not needed if 1 2 are performed promptly.
Appendix A
Performing airway assistance.
  1. If no neck injury is suspected, place in the "Sniffing" position by tilting the head back and extending the front of the neck.
  2. Apply the "Jaw Thrust" to move the tongue out of the way without flexing the neck: Place thumb fingers from both hands under the back of the jaw and thrust the jaw forward so that the chin sticks out. This should also hurt the patient, allowing you to judge depth of coma. :)
  3. Tilt the head to the side to allow vomit and snot to drain out.

From conversations on alt.drugs.caffeine:

The toxic dose is going to vary from person to person, depending primarily on built-up tolerance. A couple people report swallowing 10 to 13 vivarin and ending up in the hospital with their stomaches pumped, while a few say they've taken that many and barely stayed awake.

A symptom lacking in the clinical manual but reported by at least two people on the net is a loss of motor ability: inability to move, speak, or even blink. The experience is consistently described as very unpleasant and not fun at all, even by those very familiar with caffeine nausea and headaches.


I didn't know there was a

I didn't know there was a such thing as caffeine poisoning I just had a lot of caffeine because I wanted to stay awake but then started to feel really blugh then threw up a lot I took some activated charcoal and am just trying to wait it out is there something I can do to help push it out my system faster

Caffeine effects still lasting 3 days later anyone ??

I went to the er Thursday night after feeling dizzy with a racing heart all test came back normal .. The doctor said he was pretty sure it was from the max dose I took of preworkout 5in a half scoops every 2 scoops was 100mg of caffeine . He also said it had other things in there that were pretty bad . It's now Sunday and all though the muscle twitches and wired feeling have gone my heart tends to race (palpitations) sometimes when I get up to do things . I've drank tons of water . Has anyone else had lasting effects like this that took longer to go away ? I did not have this issue prior I'm sure I would have noticed considering I go to the gym my heart beat would me sky rocket .

Coffee Overdose - hell, don't drink coffee anymore

Drank a big cup of coffee with 30 teaspoons of expensive ground coffee. I think there was like 2000 g of caffeine in it. Result? Vomiting for 2 days. Extreme restlessness, nightmarish anxiety, constant pacing lasted 7 days. Anxiety, especially in the morning and mid-day lasted for more than a month. Never again. I overdosed on caffeine because I was trying to treat my Post-SSRI Sexual Dysfunction, coz I read that caffeine increases dopamine. Which did not work at all.

5 hour energy

I have found this post very helpful. I am a 29 year old adult male. I haven't had any caffeine in at least 6 months. This morning I was very tired after staying up to late last night. I had such a
busy day ahead of me at work, so I decided to try a 5 hour energy shot for the very first time. About 30 min after drinking it, I started feeling very dizzy, shaky, and light headed. I freaked out and had a panic attack. Luckily I was near
A doctors office, and I went in. They said it was a caffeine overdose. I drank lots of water and felt a little better a few hours later,
but still not great. I am now drinking a few beers to help calm my nerves. I'll never drink a 5 hour energy again!


Can you die from 2.5 cups of coffee if you are not a grown adult? (Not a child either, like 16) sorry that this is a stupid question...

Coffee helps to prevent diabetes

As i read in the comments above, coffee does help preventing diabetes. But too much coffee can also bring you others complications. An healthy body is a matter of balance. The key is an healthy diet to prevent developping diabetes.

inhibit hIAPP with coffee

Recently researchers have found that there are certain compounds in coffee that inhibit hIAPP (human islet amyloid polypeptide). It seems hIAPP is one of the causes for diabetes as it directly impacts the pancreas and the insulin producing capability.

But it makes diabetes worse

But it makes diabetes worse and makes blood sugar more difficult to control. It does that with normal subject as well.

How long are the effects felt after a panic attack?

I'm not a big caffeine person, only really consumed choclate and enjoyed the very odd coffe or tea. About a month ago I was sitting with a friend and I consumed about 5 cups of tea and totally lost it, and thought I was going to die. The effects of this first incident lasted about 5 days and then I thought I was coming back to reality. But then while eating dinner I swallowed a carrot that sort of got caught in my throat and that spawned a massive panic attack which at the time I didn't know what it was as I thought I was seriously going to die. The effects of that one lasted until I had another one about 3 days later which really came out of nowhere, nothing triggered it. Since then I have had some mild ones but nothing too dramatic. But the problem with me at the moment is I don't feel 100%, and have moments of unreality and a feeling that there is something not functioning properly within my brain. After the second panic attack I have ceased any caffiene and have been eating very well. I find it hard to concentrate for too long without that feeling creaping up on me which feels sometimes like my vital force is out of sync. Don't get me wrong, I can perform all my tasks but have this feel of I'm not really there. Please if there is anyone out there who could give me some knowledge on what I am going through that would be appreciated. I don't usually ask for help, but its been over a month now.

How to Handle Panic Attacks

So first let's validate what you are feeling.  It is real, and for some can resemble a stroke or heart attack.  So how do you manage?  Know your triggers, focus on other things, practice proper breathing exercises, WALK, WALK, WALK, and have an emergency backup plan AKA (anxiety medication).
As a busy working mom balancing work and life, I can tell you that the better you understand what sets in motion the attacks, the better equipped you will be to head them off at the pass.  You can control them, but you must be confident in that first.
Mind & Body: When the feeling comes open the window, drink/sip some water, call a friend, pray, breath, walk, meditate or even sing.
Triggers: STRESS!!!, caffeine, excitement (good news)...ect.
Managing: Maintain focus (on something else or the feeling will own you and take over).
Cut out triggers like coffee or sleeping pills (for a little bit). Make your doctor aware so that you can have a backup plan such as anxiety medication.
1. Panic attacks can be delayed and can come from something stressful from a week ago.  Basically try to manage your stress.
2. Walking regularly really puts those attacks in check.
3. Panic Disorder is a little more intense with loss of hearing, vision, and possible fainting. They may feel like a stroke or heart attack and at this point you should have some sort of medication for them.
4. Identify foods that trigger attacks and stay away from them.
5. Remind yourself that you are not going crazy and you will not die from a panic attack, why do I say this?  Because unfortunately during an attack you actually do feel like you are fading away similar to what folks describe as dying.  Once you have established that confidence and know you are not dying, you will be able to manage a panic attack that is already in progress.
Note: Not everyone experiences panic attacks the same way and not all of what is listed here will apply.
Hope this was helpful.

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