LD50s for Various Substances (with ratios regarding relative safety/toxicity)







LSD 46 mg/Kg iv ratónes 0.25 mg o 9200
16.5 mg/Kg iv ratas 3300
3 mg/Kg iv conejos 60
PSILOCIBINA 285 mg/Kg iv ratones 12-20 mg o 1187 - 712
280 mg/Kg iv ratas 1166 - 700
12.5 mg/Kg iv conejos 52 - 31
DMT 110 mg/kg im ratón 60 mg im 91
DET 28 mg/kg iv ratón 60 mg im/po 23
5-MEO-DMT 115 mg/kg ip ratón 6 mg p 958
DPT 20 mg/kg iv ratón 60 mg po 16
DIPT 26 mg/kg iv ratón 30 mg o 43
THC 1270 mg/Kg o ratas (m) 20mg o 3175
730 mg/Kg o ratas (h) 20mg o 1825
105.7 mg/Kg iv ratas 5mg(smoked) 1057
42 mg/Kg (inhalación) ratas 5mg(smoked) 420
CAFEINA 127 mg/Kg o ratones (macho) 100-200mg o 63 - 31
137 mg/Kg o ratones (hembra) c 68 - 34
230 mg/Kg o hamster (macho) c 115 - 57
249 mg/Kg o hamster (female) c 124 - 62
355 mg/Kg o rata (macho) c 177 - 88
247 mg/Kg o rata (hembra) c 123 - 61
246 mg/Kg o conejo (macho) c 123 - 61
227 mg/Kg o conejo (hembra) c 113 - 56
NICOTINA 230 mg/Kg o ratones
9.5 mg/Kg ip ratones .7mg(smoked) 675
.3 mg/Kg iv ratones 21
ASPIRINA 1100 mg/Kg o ratones 325mg o 169
1500 mg/Kg o ratas 230
ACETAMINOPHEN 338 mg/Kg o ratones 500mg o 33.8
500 mg/Kg ip ratones 50
VITAMINA A 2570 mg/Kg o ratones 10-20mg o 12850 - 6425
1510 mg/Kg ip ratones 7550 - 3775
ESTRICNINA 96 mg/Kg iv ratas .25mg o 192 (relativo a una dosis de LSD)
SUCCINYL CHOLINE .45 mg/Kg iv ratones
VX (GAS NERVIOSO) .0154 mg/Kg iv conejos 0 mg none


iv=intravenoso (inyectado en la vena)
ip=intraperitoneal (inyectado dentro de la cavidad corporal)
im=intramuscular (inyectado dentro de los músculos)
p=parenteral (inhalado o esnifado)
mg/Kg=milligramos de droga por kilo de peso corporal
mg=milligramos de droga

Substance Reckoned Safety Ratio (Closest Available Analogy)

Vitamin A 9637 (ratones oral:human oral 15mg)
LSD 4816 (rodents iv:human oral 0.25mg),averaged
5-MeO-DMT 958 (ratones intraperitoneal:human parenteral 6mg)
Psilocybin 641 (rodents iv:human oral 16mg),averaged
THC 420 (ratasinhaled:human smoked 5mg)
Aspirin 199 (rodents oral:human oral 325mg),averaged
DMT 91 (ratones intramuscular:human intramuscular 60mg)
Caffeine 84 (rodents oral:human oral 150mg),averaged
Acetaminophen 34 (ratones oral:human oral 500mg)
Nicotine 21 (ratones iv:human smoked 0.7mg)
VX (Nerve Gas) 0 (just a hunch)



All LD50's are normalized to milligrams/Kilogram of animal's body weight.

All LD50 data were found in the "The Merck Index, 11th edition".

The "LD50" is the dose of a substance that will kill a selected species of experimental animal 50% of the time.

"Typical Human Dose" info is taken from various sources, including "Burger's Medicinal Chemistry", "Journal of Psychedelic Drugs", "The Merck Manual", "NIOSH Registry of Toxic Effects of Chemical Substances", cigarette packages, No-Doz bottles, etc.

The "Safety Ratio" was fabricated for the purpose of this information file based on notions of relative toxicity expressed in various pharmacology textbooks and in a taped lecture by Andrew Weil MD.

The "Safety Ratio" is based on the dubious assumption that a human has the same LD50 as an experimental animal in relation to body weight. The Typical Human Dose for "recreational" or therapeutic purposes is expressed in milligrams and the number of those doses required to reach the corresponding LD50 for a 50 Kilogram (110 pound) human is computed. The assumption here is that the margin of safety for a drug is proportional to the number of typical doses a person would have to take in order to have a 50% chance of dropping dead were they a giant rodent. According to this reasoning, the higher the "Safety Ratio" is, the less toxic the drug is at normal dosages.

One might well argue that it is of questionable utility to compare toxic responses between various species using different routes of administration. Needless to say, many rodents have died for our sins.


It was later pointed out that what is called above a "safety ratio" is roughly equivalent to the pharmacological measure known as the "Therapeutic Index". The therapeutic index is a measure of the toxicity of a drug relative to it's usual therapeutic dose.

The NIOSH Registry of Toxic Effects of Chemical Substances also lists most published LD50 measurements, but does so uncritically. It's quite useful as a point of reference.

 Miembro HispaVista / HispaClick