Caffeine is a very common substance that is contained in chocolate, soft drinks, tea, coffee, and can also be purchased as capsules, tablets, or powder. The chart below shows dosages for common Caffeine products measured in milligrams (mg).
Please Note: Caffeine in concentrated forms such as pills or powders can accidentally be taken in sufficient quantities to cause
vomiting, unconsciousness, and death. A single box of Vivarin or No-Doze (US Products) can be fatal
if taken at one time. Although possible with coffee or other strongly caffeinated drink, it generally
requires much more awareness of the large dosage before dangerous levels are reached.
Oral Caffeine Dosages |
| Threshold | 10 - 20 mg |
| Common | 50 - 150 mg |
| Strong | 150 - 400 mg |
| Heavy | 400 + mg |
| Lethal | 3-20 grams oral (estimated, see below) |
| LD50 (Lethal Dose*) | 192 mg/kg in rats |
|
Onset : 5 - 10 minutes
Duration : 1.5 - 5 hours
Normal After Effects : up to 24 hours
|
* LD50 = dose which will kill 50% of the tested animals. It is estimated that fatal doses for humans
are between 3 and 20 grams of caffeine taken orally, depending on body weight and tolerance.
See
References and Notes below for more information about case reports of caffeine fatalities.
Erowid editors thought they remembered a citation for a death involving 3 grams of caffeine ingested orally, but have been unable to locate that documentation. The references below are to fatal and non-fatal overdose ingestions, many of which were suicides. The highest documented survived dose is 20 grams of caffeine and the lowest well documented death listed here is from 10 grams of caffeine ingested orally. If anyone knows of other well documented deaths we should include here, please let us know. Also, we do not have any of the full texts of any of the articles we link to PubMed below, if you have access to these papers, please consider sending us a reprint.
- Kerrigan S, Lindsey T. Fatal caffeine overdose: two case reports. Forensic Sci Int, 2005; 153(1):67-9
[ Abstract ]
39 yr old female found dead with 192/mgL caffeine in femoral blood. 29 yr old male had taken 'a bottle of caffeine pills the day before' died while in hospital and had 567 mg / L caffeine in femoral blood.
- Holmgren P, Norden-Pettersson L, Ahlner J. Caffeine fatalities--four case reports. Forensic Sci Int, 2004; 139(1):71-3 [ Abstract ]
Four cases reported: 54 yr old male died after taking 100 x 100mg caffeine tablets resulting in 173mg/L in femoral blood. 21 yr old male died after ingesting 200 x 100mg caffeine tablets resulting in 210mg/L in femoral blood. 31 yr old male died after ingesting 100 x 100mg tablets resulting in 153 mg/L in blood sample. 47 yr old female died after ingesting 100 tablets containing both caffeine and ephedrine resulting in 200 mg/L of caffeine and 4.8 mg/L of ephedrine.
- Garriott JC, Simmons LM, Poklis A, Mackell MA. Five cases of fatal overdose from caffeine-containing 'look-alike' drugs. J Anal Toxicol, 1985; 9(3):141-3. [ Abstract ]
Mixed ephedrine and caffeine fatalities, showed blood levels of 130-344 mg/L caffeine and three also had 3.5-20.5 mg/L of ephedrine.
- Winek CL, Wahba WW, Winek CL Jr, Balzer TW. Drug and chemical blood-level data 2001. Forensic Sci Int, 2001; 122(2-3):107-23 [ Abstract ]
No citation is given, but Winek et al.'s comprehensive therapeutic and toxic blood level data is considered a good source. Winek et al. give "> 100 ug/ml" as the "Lethal" level for caffeine. That works out to 100mg/L.
- McGee MB. Caffeine poisoning in a 19-year-old female. J Forensic Sci. 1980 Jan;25(1):29-32. [ Abstract ]
19 yr old female died after ingesting over the counter appetite suppresant. Dose unknown.
- Walsh I, Wasserman GS, Mestad P, Lanman RC. Near-fatal caffeine intoxication treated with peritoneal dialysis. Pediatr Emerg Care. 1987 Dec;3(4):244-9. [ Abstract ]
2 yr old female died after orally ingesting caffeine.
- Mrvos RM, Reilly PE, Dean BS, Krenzelok EP. Massive caffeine ingestion resulting in death. Vet Hum Toxicol. 1989 Dec;31(6):571-2. [ Abstract ]
22 yr old female died after ingesting diet pills. Highest known blood levels 1,560 mg/L.
Non-Fatalities
- Forman J, Aizer A, Young CR. Myocardial infarction resulting from caffeine overdose in an anorectic woman. Ann Emerg Med. 1997 Jan;29(1):178-80.
[ Abstract ]
Non-Fatal. 20 yr old bulimic woman ingested 20g caffeine, did not die but suffered subendocardial infarction.
- Leson CL, McGuigan MA, Bryson SM. Caffeine overdose in an adolescent male. J Toxicol Clin Toxicol. 1988;26(5-6):407-15. [ Abstract ]
Non-Fatal. 16 yr old male ingested estimated 6-8grams caffeine and survived with hospital care.
- Dietrich AM, Mortensen ME. Presentation and management of an acute caffeine overdose. Pediatr Emerg Care. 1990 Dec;6(4):296-8. [ Abstract ]
Non-Fatal. 1 yr old female ingested 2-3 grams caffeine (200-300mg/kg), showed blood levels of 385 mg/L and survived with hospital care.
