Form the Caf. FAQ ar Lycaeum.org
What happens when 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
Recent consumption of caffeine, usually in excess of 250 mg.
At least five of the following signs:
restlessness
nervousness
excitement
insomnia
flushed face
diuresis
gastrointestinal disturbance
muscle twitching
rambling flow of thought and speech
tachycardia or cardiac arrhythmia
periods of inexhaustibility
psychomotor agitation
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.
Symptoms
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.
Treatment
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
