Put simply, LSD does not cause death at recreational or therapeutic doses (less than 500 ug / 0.5 mg). An increase in news articles in 2012/2013 suggesting deaths related to LSD are almost all related to 25I-NBOMe and 25C-NBOMe, two new chemicals, available on blotter, but completely different from LSD. While there are substantial reasons why users should be cautious about LSD use (see LSD Health), death is not a major risk.
Less than a handful of human deaths have been tied in the medical literature to the pharmacological effects of LSD, and none of these deaths have been unquestionably attributable to LSD's actions. The clearest case was documented by Fysh et al. in 1985; however, they fail to explain the circumstances of the death, only discussing the toxicological assessment, casting some doubt that the only explanation for the death was LSD.
Estimates of lethal doses of LSD are higher than 10 mg (10,000 ug) administered orally, more than 100 times a normal moderate dose of LSD (100 ug). The administration of this amount would require the ingestion of more than 200 units of street blotter, which typically contain about 50 ug of LSD (as of late 2010). LSD has been used by tens of millions of people over the last 50 years and has been administered to tens of thousands of patients in psychotherapeutic settings (mostly prior to 1960).
Some suicides have been tied to the use of LSD, though it is difficult to positively link an individual's choice to take their own life with their past use of LSD. In general, LSD is not reported to substantially increase the risk of suicide and those who do commit suicide after taking LSD are likely to have suffered from pre-existing suicidal tendencies.
Some deaths have been associated with inebriated or combative behavior while under the influence of LSD, including falling or jumping from a height or dying after being beaten by police.
Because the numbers of fatalities associated with LSD are so low, it is difficult to determine the risk of death associated with LSD. Erowid estimates that the risk of death from taking LSD is probably less than one death per million LSD use sessions, with risk of death higher among those predisposed to suicide and among those without a sober sitter present to help avoid accidents or fights.
In his 2001 book "Illegal Drugs: A Compete Guide to Their History, Chemistry, Use and Abuse", Dr Paul Gahlinger states "LSD is not toxic in the biological sense.". A 2008 review of the scientific literature titled "The Pharmacology of Lysergic Acid Diethylamide: A Review", by Passie et al. gives the number of pharmacological fatalities from LSD as zero: "There have been no documented human deaths from an LSD overdose."
PHARMACOLOGICAL FATALITIES #
Pharmacological fatalities are those deaths caused by the direct action of a plant or drug in the body, not including deaths caused by accidents or as a result of inebriated behavior. Generally, LSD is considered to have a very low risk of death. As Haddad and Winchester stated in 1990, "No well-documented human deaths resulting directly from the toxic effects of LSD itself have occurred, though LSD has been implicated in accidental deaths, suicides, and homicides."1 And in Psychedelics Encyclopedia, Peter Stafford summarizes:
For those concerned about immediate medical hazards in ingesting LSD [...] Abram Hoffer has estimated, on the basis of animal studies, that the half-lethal human dose--meaning half would die (a standard measure for drugs)--would be about 14,000 [ug]. But one person who took 40 mg. (40,000 [ug]) survived. In the only case of death reportedly caused by overdose ([Griggs and Ward, 1977]), the quantity of LSD in the blood indicated that 320 mg. (320,000 [ug]) had been injected intravenously.2
Possible Pharmacological Fatalities
Though LSD can result in increased body temperature and vasoconstriction at high doses, there are less than a handful of documented deaths or near-fatal medical cases relating to the pharmacological action of LSD in humans. None of these include enough documentation to prove unquestionably that LSD has, by itself, resulted in a person's death. Below are the best documented possible pharmacological fatalities that we have been able to find attributed to LSD.
Incident: 25 Year Old Male, 1985 #
The lack of specifics about the context or any documented symptoms the decedent had leaves some doubt about the finding that this was an LSD-caused death. The patient died 16 hours after being admitted to the hospital and no details are given about his condition. In later cases (such as those of Martin Cotton or William Parker Martin), LSD was listed as a cause of death by a coroner where more plausible causes of death were the injuries received in fights with police officers. We know nothing of the specifics of what lead to this unidentified man's death.
Fysh RR, Oon MCH, Robinson KN, Smith RN, et al. "A Fatal Poisoning with LSD". Forensic Sci Int 1985 Jun-Jul;28(2):109-13.
"Radioimmunoassay, high-performance liquid chromatography and capillary gas chromatography-mass spectrometry were used to detect and measure LSD in the first reported case of fatal poisoning by LSD. [...] In a recent case [...] a 25-year-old male died 16 h after being admitted to hospital, and a Coroner's enquiry concluded, on the basis of the medical and toxicological evidence, that the actual cause of death was poisoning by LSD. This paper describes the toxicological aspects of the case in which LSD was analysed in ante- and post-mortem samples by various techniques."
Incident: 34-year old male, 1977 #
Questions remain about the cause of death in this case, as a month passed between the time of the victim's death and his body's discovery (complete with rodent bites) in a warehouse.
Griggs EA, Ward M. "LSD Toxicity: A Suspected Cause of Death". J Ky Med Assoc. 1977 Apr;75(4):172-3.
"An extremely high liver tissue level of lysergic acid diethylamide (LSD) was measured in a 34-year-old male in whom autopsy showed no anatomic cause of death. Death from LSD overdose apparently has not been previously confirmed toxicologically. The possibility that this case represents death due to toxic effect of LSD is discussed."
"A partially clothed 34-year-old male was observed while engaged in bizarre behavior, and was subsequently accosted during an attempted break-in in November, 1975. He fled the scene and was found dead in a deserted warehouse, one month later. An autopsy was performed to ascertain, the cause of death."
Incident: No deaths, but eight near-fatal overdoses, 1975 #
These case reports do not document a death, but do provide details about serum and gastric levels of LSD after a group of major non-fatal overdoses. The article describing these case reports explains that these patients mistook the powdered LSD for cocaine.
Klock JC, Boerner U, Becker CE. "Coma, Hyperthermia, and Bleeding Associated with Massive LSD Overdose, A Report of Eight Cases". Clin Toxicol 1975;8(2):191-203.
"Eight patients were seen within 15 min of intranasal self-administration of large amounts of pure D-lysergic acid diethylamide (LSD) tartrate powder. Emesis and collapse occurred along with sign of sympathetic overactivity, hyperthermia, coma, and respiratory arrest. Mild generalized bleeding occurred in several patients and evidence of platelet dysfunction was present in all. Serum and gastric concentrations of LSD tartrate ranged from 2.1 to 26 ng/ml and 1000 to 7000 ug/100 ml, respectively. With supportive care, all patients recovered."
https://www.erowid.org/c...cals/lsd/lsd_death.shtml